Pediatric Cardiac Surgery: A Challenge of Skill and Creativity in Constant Search Results

Pediatric cardiac surgery has been available for many years in several developing countries, thanks to the hard work and creative adaptation of individuals who were able to stretch the limits of their abilities in spite of the restricted resources. Limited resources were a constant problem forcing us to focus on short-term creativity about tomorrow’s needs. A great deal of energy in the form of leadership and negotiations was used in order to encourage people to improve themselves and carry on working diligently despite the low pay.

a shunt is usually a temporary measure designed to alleviate symptoms until such time that the patient is in better condition to undergo complete repair.The usual approach is performed by systemic-pulmonary shunts using right or left thoracotomy and today we used median sternotomy approach, for interposition of polytetrafluoroethylene ( PTFE) vascular graft between the subclavian and pulmonary arteries.
In preterm or low birth weight children it is often found a subclavian artery of small diameter (2.5 to 3.0 mm), which could jeopardize the flow of the shunt due to difference in calibers between this vessel and the PTFE graft, compromising the patient's life. In order to overcome this anatomical difficulty, since 1986, we have been performing technical modifications of the B-T shunt, with PTFE prosthesis anastomosed to the brachiocephalic (innominate artery) trunk, always larger in diameter than the subclavian artery. To this end, the approach by thoracotomy was always done by other side of the descending aorta or the same side of the origin of the brachiocephalic trunk (BCT). This technique is an original contribution of our group.
This approach causes essentially a trauma to the lungs and some difficulty for dissection and definitive surgical ligation during later correction.
Since 1990 we have held the B-T shunt between the innominate artery and the right pulmonary artery, through a median thoracotomy, allowing a more comfortable procedure with hemodynamic and oximetric patient's control.
This technique is viable with advantages over lateral approach due to cutting easier access, vascular structure dissection, avoiding lung trauma; on the other hand, a rapid cardiopulmonary bypass is installed, if hypoxic crisis occurs during the surgical procedure. (Fig. 1)   Fig. 1. Plot of the Blalock-Taussig shunt. Right thoracotomy approach and interposition of polytetrafluoroethylene (PTFE) graft between the brachiocephalic trunk (BCT) and the right pulmonary artery (RPA). SVC: superior vena cava.

Patient information
Sixty four patients; mean age of the patients was 29.3 ± 1.0 days (1 day to 17 years-old). Five neonates with mean weigh 2,600 gr (1,800 to 3,000 gr), were operated between 1987 and 1988, with interposition of PTFE graft between the BCT and right pulmonary artery (RPA), due to the reduced diameter of the subclavian artery. Four patients had hospital discharge with pervious BT shunt. The diagnosis of cardiac malformation was: T. of Fallot, pulmonary Atresia with intact ventricular septum, Tricuspid atresia and Univentricular heart. These first 5 patients were operated by lateral thoracotomy, subsequently, 30 cases were operated using median thoracotomy approach. In all cases it was employed a PTFE graft ( 3.5 -4.0 mm) , anastomosed to BCT. (Fig.2) Fig. 2. Surgical picture of Blalock-Taussig shunt in a patient with pulmonary atresia with intact ventricular septum. Median thoracotomy approach: Interposition of polytetrafluoroethylene (PTFE) graft (arrow) between the brachiocephalic trunk (BCT) and the right pulmonary artery (RPA). RA: right atrium, Ao: aorta.

Results
There were 2 (5.7%) deaths in this group of 35 patients during the early postoperative period by sepsis and respiratory distress. Thirty three patients were submitted to Dopplerechocardiogram exam; all patients presented pervious B-T shunt.

First stage: Bidirectional Glenn
The Fontan repair and its modifications can be performed in selected groups of patients which report relatively low rates of mortality. Among the later modifications of the Fontantype procedure, a significant alteration was introduced by de Leval and associates when they described the Intracardiac cavopulmonary connection (ICPC). The modified Fontan procedure represents the final stage for the palliation of hearts with single-ventricle physiology.
The introduction of a bidirectional Glenn (BDG) procedure preceding an ICPC extends the indication for the Fontan procedure. High-risk Fontan candidates who have undergone BDG and staged ICPC (staged strategy) have exhibited excellent clinical results. However, the exact mechanism for the superiority of BDG is still poorly understood.
In addition, several management strategies have been incorporated in order to reduce the mortality: universal risk factors that have resulted in better patient selection; the use of tunnel fenestration; and the use of modified ultrafiltration after cardiopulmonary bypass (CPB).
Many reports discussed the importance of the pulmonary artery size and systemic ventricular function in Fontan candidates. A few studies undertaken to investigate in detail the hemodynamic conditions in Fontan circulation focusing on the ventricular efficiency.
When the ICPC was performed, the lower resting heart rate or the higher peak heart rate, are frequently part of the operation history which are each weakly associated with better physical function.
Cardiac arrhythmias are very common in patients submitted to intracardiac lateral tunnel using a long suture line on the right atrial wall.

Patient information
In our Institution, following the Great Ormond Street Hospital's protocol behavior the total cavopulmonary connection is performed in staged strategy: in March 1990, we performed the first BDG (1 st stage) and in April, 1992 the same patient was completed to TCPC (2 nd stage), with good results.
This successful technique was adopted, rapidly, by Institutions with Pediatric Cardiovascular Surgery, all over the country, and abandoning the atrio-pulmonary anastomosis.
Between March, 1990 andDecember, 2008; 105 patients were submitted to BDG in our Institution. In this study we included 52 patients of these series, consisting of 27 females and 25 males, mean age of the patients was 3.3 ± 1.0 years (1 to 8 years-old) and underwent ICPC. These patients were a consecutive series. Table1.

Hemodynamic variables
The preoperative hemodynamic variables: heart rate, mean pulmonary artery pressure, ejection fraction and Nakata pulmonary arterial index were evaluated in all patients, according to the protocol established by our Institution.
The operative procedures before BDG were as follows: a modified Blalock-Taussig shunt was performed in 39 patients and pulmonary artery banding in 9 patients. In 52 (49.5%) patients the ICPC was indicated after the first stage of the BDG. www.intechopen.com

Patient inclusion criteria
The indication for intra-atrial cavopulmonary anastomosis surgery included patients: Fifty two patients had a previous bidirectional cavopulmonary shunt performed by direct end-to-side anastomosis between the SVC and the right pulmonary artery (RPA) (bidirectional Glenn). This group was referred to ICPC 1 to 5 years later: In 42 (80.7 %) cases it was indicated an intra-atrial lateral tunnel and in the last 10 (19.2%) consecutive patients, an intra-atrial conduit technique was performed.

Operative technique
Anesthesia was performed by the standard intravenous access with fentanyl, midazolam and pancuronium, for muscle relaxation. Although the ICPC was performed by Aortic SVC and inferior vena cava (IVC) cannulation to install a cardiopulmonary bypass (CPB) and perform the surgical approach with beating heart. When heart arrest was necessary, myocardial preservation was achieved with a cold blood cardioplegic solution. We reported our surgical technique in previous publications.

Intra-atrial lateral tunnel
Forty two (80.7%) patients had a previous BDG shunt performed by direct end-to-side anastomosis between the SVC and the RPA. Figure 4. These patients were operated by the intra-atrial lateral tunnel technique performed with a bovine pericardium patch. Figure 5.
The details of the surgical procedure employed are described as follows: After dissection of BDG, the operation was performed using CPB, moderated hypothermia and beating heart.
After the right atrium approach, the lateral tunnel was performed using a bovine pericardium patch sutured around the IVC ostium and on the lateral right atrium wall. The upper tip of the tunnel is connected to the SVC ostium. The RPA is open and stitched to the lateral tunnel by the proximal tip of the SVC. Finally, the anastomosis is enlarged using a bovine pericardium patch.  www.intechopen.com

Intra-atrial conduit
In the last 10 (19.2%) consecutive patients a technique modification was introduced to avoid the lateral suture in the free wall of the right atrium (RA) and cardiac arrhythmias. Figure 6.
After a longitudinal RA approach, a corrugated bovine pericardium tube, measuring 18 to 20 mm of diameter was sutured around the ostium of the IVC and SVC.
Finally, the connection with an RPA was performed using the same technique of the lateral tunnel. This technique is a original contribution of our group.
In both techniques a 4 mm trap-door type fenestration was performed promoting its spontaneous occlusion during the follow-up. Fig. 6. Surgical photography-The intra-atrial conduit operation is performed, implanting a corrugated bovine pericardium tube around the ostium of the superior and inferior vena cava.

Statistical analysis
The relations of cardiac arrhythmias between two groups were evaluated with the exact Fisher test. A p value of less than 0.05 or 5% was considered to be significant.

Results
There were 2 hospital deaths (mortality 2.8%) in the intra-atrial lateral tunnel group: one patient presented acute renal insufficiency not reverted with peritoneal dialysis and compromised ventricular function, resulting in death 30 days after operation. The other patient presented multiple-organ failure resulting in death, 20 days after operation.
There were no records of mortality among the 10 (19.3%) patients submitted to intra-atrial conduit implant.
The mean cardiopulmonary bypass time was 114 ± 27 minutes (range 50 to 152). Thirty patients underwent aortic cross-clamping, and the mean aortic cross-clamp time was 42 ± 33 minutes (range 20 to 80). The mean duration of the mechanical ventilation was 12 hours (range 0 to 204). The average duration of intensive care unit stay was 5 days (range 3 to 29), the average duration of chest tube drainage was 6 days (range 2 to 38), the average duration of postoperative hospital stay was 16 days (range 7 to 60), and the average follow-up period was 87 ± 45 months (range 6 to 204). All of these patients received anti-platelet drug therapy during the follow-up.  There was a significant improvement of O2 saturation after surgery in both groups: Intraatrial lateral group, SO2: before M=78 %, after M= 92 %; Intra-atrial conduit, SO2: before M= 79 %, after M= 93 %.
The postoperative data were presented at  In the intra-atrial lateral tunnel group: consisted of 40 (80%) surviving patients, it was observed the presence of cardiac arrhythmias in 13 (30.9%) cases and there were statistical differences (p=0.048) when comparing both groups. Ten (23.8%) patients received antiarrhythmic drugs daily.
One patient developed late postoperative paroxysmal supraventricular tachycardia and was treated with a selective ß blocker.
However, no arrhythmias were detected in the intra-atrial conduit group.
All patients were submitted to periodic clinical and cardiac imaging exam: Dopplerechocardiogram each 6 month; MNR and CT after 2 years of operation.   . Probability of overall reoperation and thromboembolism incidence in the last 9 years, after performing the lateral tunnel -Intracardiac conduit surgery. www.intechopen.com

Discussion
Throughout the years, the experience with Fontan operation has been increasing and has opened the way to a much wider application of this principle. The subsequent evolution of the cavopulmonary connection, thus avoiding stasis of the blood in the right atrium as seen in the atrial-pulmonary anastomosis or the turbulence seen in cases of atrial-ventriculararterial connections. The hemodynamic concept of Jonas & Castaneda demonstrated the advantages of laminar flows, with less outflow and lower incidence of arrhythmias and thrombosis, introducing new surgical techniques. A number of major risk factors have been identified and managed by several modifications of the original Fontan procedure and late outcome of the Fontan circulation is encouraging. Ventricular morphology, surgical techniques and fenestration do not appear to influence early or late outcome. In the preoperative preparation of the patient is important to detect the impaired ventricular function and elevated pulmonary artery pressure because it has an adverse influence on both early and late outcome.
Reoperations are common with small preoperative pulmonary artery size being an additional risk factor.
This report focused its attention on the only two different variant options of intracardiac connection of the superior vena cava and inferior vena cava with the right pulmonary artery: intra-atrial lateral tunnel and intra-atrial conduit implantation, in order to reduce the cardiac arrhythmias and tunnel thrombosis.
In our Institution, the total cavopulmonary connection is performed in a staged strategy. An alternative approach is to make connections between both ends of the divided superior vena cava and the pulmonary artery and to place a patch within the right atrium at the entrance site of the superior vena cava. This procedure was performed at the São Paulo Federal University, being the first institution in the country to adopt this procedure, and then rapidly expand to other pediatric cardiac surgery centers in the country, looking for successful results. To complete the Fontan operation, the removal of this patch facilitates the connection between the IVC to RPA, with the construction of an intra-atrial tunnel or implantation of intra-atrial corrugated conduit of bovine pericardium, sutured to IVC and SVC ostium, facilitated by the proximal stump of the SVC with the RPA. This technique is an original contribution of our group.
In this series, 40 surviving patients with lateral tunnel Fontan presented 13 (30.9%) cases with cardiac arrhythmias. To prevent frequent cardiac arrhythmias we changed the lateral tunnel technique to the intra-atrial conduit implantation. A corrugated bovine pericardium tube is sutured around the ostium of the inferior vena cava and superior vena cava avoiding the right atrium wall stitched line. None of the last 10 patients, with intra-atrial conduit,submitted to Holter study during the follow-up, presented cardiac arrhythmias in 3 different moments: at rest, during exercise or sleeping. No patient was referred to pacemaker implant.
The postoperative period, early and late arrhythmias after a Fontan operation seem to be a consequence of adverse hemodynamic function. In the early follow-up is, therefore, poor even when the patient is restored to the sinus rhythm. Medical and surgical modifications in order to improve the hemodynamic disturbances associated with arrhythmias are therefore indicated.
Other authors described that Fontan conversion with concomitant arrhythmia surgery and permanent pacemaker placement are safe and improve the New York Heart Association functional class, and has a low incidence of recurrent arrhythmias. In most patients, concomitant permanent pacemakers are needed. The intra-atrial lateral tunnel (ILT) operation results in excellent midterm outcome even when used in patients with complex anatomy.
The incidence of postoperative atrial tachyarrhythmias is low and depends largely on the underlying cardiac morphology and incidence of preoperative arrhythmia. The good midterm outcome after an ILT operation should serve as a basis for comparison with other surgical alternatives to complete the Fontan circulation. Outcome after staged ILT operations is good, with comparable freedom from late re-operations and freedom from Fontan failure at 6-year follow-up. Right ventricular morphology was identified as a risk factor for arrhythmias.
The staged strategy is considered to be one of the most important factors for obtaining excellent clinical results in the treatment of high-risk Fontan candidates, with low mortality. The volume load reduction of bidirectional Glenn preceding intracardiac cavopulmonary connection allowed for any afterload mismatch to be corrected, thereby improving ventricular efficiency after staged intracardiac cavopulmonary connection in clinical patients.
The most significant findings in patients submitted to Fontan procedure who underwent a staged operation are: 1-The volume-load reduction of the systemic ventricle, resulted in an improvement of the contractility in both: after bidirectional Glenn and after staged intracardiac cavopulmonary connection; 2-Afterload increased both: after bidirectional Glenn and after staged intracardiac cavopulmonary connection and 3-These changes resulted in an improvement of ventricular efficiency during the interval period between bidirectional Glenn and intracardiac cavopulmonary connection.
Improved early morbidity and mortality after Fontan operation was presented in clinical experience of the Mayo Clinic, from 1987 to 1992.
In our Institution the study of the first 18 surviving patients submitted to bidirectional Glenn were available with cineangiographic exam showed a significant reduction in the total index of the left pulmonary artery after mean follow-up of 23.6 months.
An alternative approach to homogeneous distribution of SVC blood flow into RPA and LPA was performing of the hemi-Fontan operation that includes atriopulmonary anastomosis employing an atriopulmonary patch directs superior vena cava flow into both pulmonary arteries and inferior vena cava flow into the ventricle, thus maintaining cardiac output (modified Glenn physiology).
The extracardiac cavopulmonary connection is other alternative to cavopulmonary connection, utilizing a non-valved conduit is gradually becoming accepted as a new alternative for the surgical treatment of certain complex congenital heart diseases. Among the advantages of the use of an extracardiac conduit is the possibility of employing it under normothermic cardiopulmonary bypass with a beating heart, which is important for the preservation of the left ventricular function. www.intechopen.com The extracardiac cavopulmonary connection, however, it is not always beneficial and among the complications that may arise are: thromboembolism, cellular hyperplasia, fibrosis and calcification and the absence of growth. All are severe complications, which can occur in the early follow-up or even months or years after the intervention and shadow the late evolution.
Another recent national experience shows: 18 consecutive patients with univentricular heart submitted to total cavopulmonary connection. These patients were operated using the extracardiac conduit procedure to make the connection between the inferior vena cava and the pulmonary circulation. Three patients died in the immediate post-operative period (hospital mortality rate: 16.6%). There were four cases of thrombosis with one case evolving to death. All the four cases were submitted to re-intervention. Apart from the case described above, a fifth case suffered from thrombosis and progressive calcification, which led to total occlusion of the conduit.
Due to this fact, the patients in this study were routinely prescribed warfarin sodium, using salicylic acetyl acid only when the use of the former was impossible or after the 12 postoperative month for the rest of their lives. This, however, did not prevent the occurrence of thrombosis in the conduit, initiating within 24 hours in one of the patients and with total occlusion of the tube, which forced replacement but this did not impede a lethal result of the complication.
The Fontan operation in its variant ways of performance was always associated with approximately 20% of thromboembolism in the post-operative period. The Kaplan & Meier actuarial curve in our series of 50 survival patients operated with the intra-atrial connection technique, followed-up by 12 to 204 months by Doppler-echocardiogram, MNR and CT reported survival of 96,1%, free of reoperations and we have not reported thromboembolism events in this period. Figure 6, 7, 8. All of our patients received anti-platelet drugs (salicylic acetyl acid), only.

Conclusion
The Bidirectional cavopulmonary anastomosis with intracardiac repair is a viable alternative for patients with RV hypoplasia. Early unloading of the functional univentricular heart by means of BDG allowed a good condition for completing the intra-atrial cavopulmonary connection.
Technical modifications of the intra-atrial operation (intra-atrial conduit implanted) have reported no cardiac arrhythmias and no prosthesis thrombosis during the follow-up. The modified surgical procedure can be a good alternative to the Fontan procedure in suitable patients.

Modified senning operation for surgical correction of simple transposition of the great arteries
Survival functional status and quality of life of patients with transposition of the great arteries (TGA), after an atrial switch operation (Senning or Mustard procedure) are reported to be reasonably good within the first two decades of life. However, in some cases the function of the systemic right ventricle deteriorates, severe tricuspid regurgitation develops or the patients suffer from arrhythmias.
Several strategies are proposed to handle those patients with failing right ventricle, such as: tricuspid valve repair, conversion to arterial switch or heart transplantation. In most of the cases, these procedures are performed after the right ventricular function has already deteriorated, as a consequence of high operative mortality In the present study we focused on the analysis of the long-term results of atrial switch procedure (Senning operation), to identify risk factors for long-term outcome and quality of life, in a group of patients with simple TGA.

Patient information
From July 1990 to December 2000, 40 consecutive patients with TGA were submitted to palliative atrial switch (Senning operation); 37 cases had atrial septal defect (ASD) and 3 cases had ASD associated to small muscular ventricular septal defect (VSD). These patients were operated the cardiovascular Division of São Paulo Federal University (UNIFESP).
Out of 39 (97.5%) surviving patients, thirty six (94.8%) cases were included in a retrospective follow-up study. Three patients, living overseas were excluded from this study.
The patients age at the moment of surgical correction was 1 to 11 months (mean 5.3 months); male 21 (52.4%). The clinic diagnostic was confirmed by Doppler-echocardiogram: d-TGA with ASD, in 37 (92.5%) cases, and ASD associated to small muscular VSD (size: 3 to 4 mm of diameter), in three (7,5%) cases, were present. All patients were submitted to Rashkind procedure prior to surgery. Table 3.

Operative technique
The surgical approach was performed by median sternotomy, employing hypothermic cardiopulmonary bypass (CPB), after vena cava and aortic cannulation; anterograte cold blood cardioplegia was used for myocardial protection, administrated every 20 minutes. During bypass assistance it was employed the conventional ultrafiltration (CUF) and after July 1996, it was associated with modified ultrafiltration (MUF), after the bypass was discontinued. In all patients it was used the Subramanian's technique modification using left atrial appendix flap, for reconstruction of the new atrial septum and dispense the use of any prosthetic tissue. Figure 10.In order to avoid tunnel stenosis, the Hegar dilator was used to measure the diameter of the vena cava ostium Figure 11. No patient required a more extensive enlargement of the right or left atrium Figure 12,13 and interrupted suture was applied, around the superior and inferior vena cava to avoid external restriction.
Small muscular VSD was kept open in three patients. The CPB was discontinued and whenever necessary administered inotropic drugs and temporary atrio-ventricular pacemaker stimulation in order to support the hemodynamic performance. www.intechopen.com

Statistical analysis
The surviving patients curve and relevant events, during the follow-up were performed according to the Kaplan-Meier's method, comparing 2or more functions by the long-rank test. For all tests, a p value of less than 0.05 was considered significant.

Results
There was only one death (1/39) (mortality=2.5%), during the follow-up time (mean: 14.7 +/-3.1 years), a 16 year-old patient with bipolar disease that due to his disease committed suicide. The actuarial survival was 97.5% (simple or with little VSD, TGA). The probability of staying in sinus rhythm, in 38 surviving patients was 71.1% (11 cases lost sinus rhythm).Eight (21.0%) patients presented moderate dysfunction of RV; three cases have mild RV dysfunction in the pre-operative period.
Preserved RV function was observed in 30 (78.9%) cases, 10 to 20 years after operation. The incidence of lost sinus rhythm and right ventricular dysfunction, increased gradually over time. Right ventricular dysfunction and active arrhythmias were not risk factors for late death.
All patients are free of reoperations and definitive pacemaker implantation.
Functional status: 28 (80%) patients were in functional class I and 7 (20%) cases, in functional class II (NYHA).  In our Institution, from 1990 until the 2000's, the Senning's procedure was indicated for infant patients with TGA + ASD, using in all cases, the Subramanian's maneuver, with very satisfactory results.Baffle-related complications were the most frequent causes and accounted for 5.4% in the Senning a group. The curves for freedom of baffle reintervention, were only slightly different within the first 15 years but began to diverge clearly after that time span. The study published by the Congenital Heart Surgeons Society in 2000 found the incidence of baffle-related complications in 173 Senning patients. All our patients were operated using the modified technique (Subramanian procedure) and no prosthetic material was used. Only two patients (2/40; 5.0%) presented stenosis of the IVC, during the early post-operative period; these patients were submitted to balloon angioplasty, with success. No patient of these series was re-operated during the late follow-up (mean 14.7 years).
In a recent publication, the inversion of the left atrial appendix, associated to autologous pericardium for venous pathway enlargement, presented retraction and calcification of the venous baffle with obstruction of the venous tunnel.
Surgery for RV dysfunction is the second most frequent indication for reoperation. Mortality associated with reoperations in general has been described to be as high as 36% in a previously published series, mainly because of conversion to the arterial switch operation. Three (7.5%) patients in our series presented moderate RV dysfunction in the pre-operative period, but maintained the same RV dysfunction after Senning's operation, during the early and late follow-up; this patients are in functional class II (NYHA).
Loss of sinus rhythm at long term has been described in patients after atrial baffle procedures, with the incidence being the same after the Senning or the Mustard procedure. However, reports present series of patients with sinus rhythm in 80.8% of the cases, 17.4 years after the Senning's procedure.
In these published articles, patients free from pacemaker implantation, inthe Senning group, were 98.7%, at 10 years and, thus, it was comparable to the findings by others series: 91% to 92% at 10 years.
Patients freedom from pacemaker insertion, at 20 years, was still > 90%. This might be related to the fact that in these patients the coronary sinus was not incised as originally described by Senning, and the atrial suture line was placed posterior to the coronary sinus.
Our surgical technique to perform the Senning's operation included: 1-ASD closure using left atrial appendix and 2-The atrial suture line was placed posterior to the coronary sinus.
In 40 patients operated, the cardiac rhythm in the early post-operative period showed: sinus rhythm in 30 (85.7%) cases and cardiac arrhythmias in 5(14.3%) cases.
In 40 consecutive operations, we had one death (hospital mortality = 2.5%); these results are possible to compare to others reported series, with mortality ranging from 2% to 5.4%. Whereas, patients with simple TGA submitted to Senning's operation, resulted in a significant difference in the relative number of complex TGA. In addition, the surgical learning curve may have been a reason for the differences in mortality between the different published reports in international issues.
Thirty five (92.1%) surviving patients had mean follow-up of 177 months (other 3 surviving patients living overseas). During late follow-up, other 3 patients presented cardiac arrhythmias. Actually, 27 (77.1%) cases maintain sinus rhythm and 8 (22.9%) cases presented cardiac arrhythmias. No pacemaker was implanted in this group of patients.
Other series presented 90.9 ± 2.3 % of surviving patients in 25 years of follow-up, after the Senning procedure and 75.9 ± 4.8%, after the Mustard procedure and thus, it was significantly different in univariate analysis. The Mustard procedure remained a significant risk factor for late death in multivariate analysis fully adjusted for all variables that were statistically significant between the 2 groups. This difference in late survival between the 2 operative procedures is not confirmed in all investigations.
Whereas, authors have observed a significantly better survival rate of patients after the Senning's operation (94% versus 77% at 15 years).
The Senning's operation is a risk factor for late death. In contrast, authors reported a similar long-term outcome for the Toronto Mustard group and the Zurich Senning group, with 75% survival after 25 years. However, they found a difference in the mode of death between a the Mustard group and the Senning group. Similar to the results of the present study, relatively more Mustard patients died of sudden death compared with the Senning patients, who died preferentially of progressive congestive heart failure.
We had a previous published report, including only the first 17 patients, submitted to Senning's operation, for correction of the simple TGA, in our Institution. In this series we have one hospital death, (early mortality 2.5%).
In thirty nine surviving patients, no cardiac cause of death was observed (only one accidental death was observed). There was no sudden death in this group; the survival rate in our Institution was 95%, with mean follow-up of 14.7% years.

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Regarding the type of atrial baffle procedure, patients with previous VSD carry a higher risk of late death than patients with intact ventricular septum. Reports show that: 90% of the patients with simple TGA but only 78% of the patients with complex TGA were alive 15 years after the Senning procedure. These data confirm the finding that the presence of a VSD is a significant risk factor for late death because VSD closure emerged as an dependent risk factor for late death in multivariate analysis.
From 1986, in our Institution, neonates with simple TGA, infants with TGA plus VSD or Taussig-Bing anomaly were referred to arterial switch operation (ASO) and VSD closure, but infants patients with diagnosis of simple TGA and simple TGA with small muscular VSD were referred to Senning's operation.
The question remains of whether the surgical procedure of VSDclosure or rather the hemodynamic consequences of a previous VSD account for the intrinsic risk of late mortality. Potential complications of VSD closure that may also lead to late RV dysfunction and consecutively to late death such as iatrogenic postoperative AV block or tricuspid insufficiency were no more frequent in patients after VSD closure.
However, freedom from pacemaker implantation was lower in patients who received VSD closure at the time of the atrial switch operation. The incidence of right bundle branch block ( RBBB), which has been associated with late development of RV dysfunction, was increased. Hence, the surgical procedure of VSD closure may have an influence on mortality in the long term.
Deterioration of the function of the systemic ventricle (RV) is a major concern in patients after atrial switch procedures. The incidence of moderate or severe RV dysfunction shows a wide variation in the literature from 8% at 12 to 18 years and 20% at 20 to 28 years, respectively. Authors found a rapid increase of RV dysfunction, after 10 years, and described the probability of normal right ventricular function to be only 52% and 39%, 10 to 15 years after the Senning's procedure in patients with simple and complex TGA, respectively. In the Lange el al study, the incidence of RV dysfunction was 16.1% at 25 years. However, in our experience with 40 consecutive cases of Senning's operation, three patients presented mild RV dysfunction, before operation and maintaining after 15 years of followup, in functional class II. The RV variability in assessing right ventricular function and the lack of a uniform definition restrict comparison. The incidence of RV dysfunction in the long term has been shown to be associated with the complexity of the heart defect, which we confirmed that this dysfunction progressed to moderate dysfunction, but maintaining the functional class II.
In our series, actually, 8 (22.8%) patients presented mild or moderate RV dysfunction and tricuspid insufficiency; these patients are medicated with ß blocking drugs and patients with tachyarrhythmias are using anti-arrhythmic drugs.

Conclusions
Our results confirm that the patients with simple TGA submitted to the Senning's procedure in the late follow-up, presented a good quality of life functional class I-II), satisfactory results (low incidence of arrhythmias, free of pacemaker implantation or reoperation) and no risk of late sudden cardiac death. www.intechopen.com

Anomalous left coronary artery from the pulmonary artery. Autogenous arterial conduit technique
Anomalous left coronary artery from pulmonary artery (ALCAPA) is a rare cardiac malformation; whose clinical symptoms are expressed in the first months of life, by congestive heart failure (CHF) of difficult clinical improvement, followed by significant mortality. The symptoms of CHF associated with functional mitral insufficiency due to papillary muscle dysfunction and ischemic changes observed in the ECG are guidelines for the diagnosis of ALCAPA.
Doppler echocardiography diagnosis, depending on the operator may have difficulty in submitting images for reliable indication for surgery. Noninvasive diagnostic methods such as computerized tomography angiography ( CT Angio) and magnetic resonance imaging (MRI) have enabled it to provide relevant information for a planned and safer surgical approach. These patients represent a model of our experience started in 1993 at the Department of Cardiovascular Surgery at São Paulo Federal University(UNIFESP), a group of 19 consecutive patients, all operated with the technique of direct re-implantation of left coronary artery from the ascending aorta and in the last three cases using the technique of autogenous arterial conduit.

Case report
Child, 9 years-old, male, with ALCAPA, who underwent corrective surgery in December 2001 with follow-up period of 9 years. The clinical examination, conducted in March 2010, showed an asymptomatic patient, without limitation during exercise, without medication in the last seven years in functional class I (NYHA). At 2 months of age, the patient was admitted to the Cardiology Department, of UNIFESP. On clinical examination the patient presented respiratory distress, tachycardia, thin wrists and pale complexion. He also presented enlarged liver and mitral systolic murmur. The ECG showed subendocardial injury current in precordial derivations, and the Doppler echocardiography showed lowered left ventricular function and moderate mitral insufficiency.

Surgical correction
After diagnosis of ALCAPA and moderate mitral insufficiency, the patient was submitted to surgical correction in December 2001 at two months of age, on cardiopulmonary bypass (CPB). During surgery it was confirmed cardiac malformation: the left coronary artery originated from the left posteriorsinus of the pulmonary valve. The heart chambers were found dilated and presented left ventricular dyskinesia, and it was observed in the epicardial surface, an exuberant intercoronary shunt between the right and left coronary system. Figure 16.
During CPB, clinical diagnostic was confirmed and was observed hypokinetic apical area of the left ventricle (LV). The patient was kept in moderate hypothermia at 28°C and the right and left pulmonary arteries were occluded. After aortic clamping was initiated the infusion of blood cardioplegic solution, injected into both vessels ascending aorta and pulmonary trunk. (Figure 17 a, b).
After dissecting the pulmonary trunk, the latter was cross-sectioned near the origin of the pulmonary arteries. We observed the ostium of the left coronary artery emerging from the left posterior sinus of the pulmonary valve, distant 25 to 30 mm from the ascending aorta.
The coronary ostium was removed from the posterior sinus of the left pulmonary sinus, along with a long flap, taken from the anterior wall of the proximal stump of the pulmonary trunk, while other similar flap was built on the side wall of the aorta below the aortic clamps, pedicle on the posterior wall of the aorta. (Figure 17 c) Fig. 16. Surgical image. External appearance of the heart, we observed the anomalous origin of left coronary artery from the pulmonary artery (ALCAPA) and significant intercoronary shunt.
The aortic and pulmonary flaps were sutured by their edges, using a 7-0 polypropylene thread, building an autogenous arterial conduit, anastomosed to the ascending aorta, about 2-3 cm above the left aortic sinus. (Figure 17 d).
No wire was needed for dissection or manipulation of the left coronary artery to approximate it to the aorta. The anterior wall of the pulmonary trunk was reconstructed with preserved bovine pericardium and there was no intervention on the mitral valve.
At the end of CPB, the patient underwent modified ultrafiltration (MUF) and administration of Dobutamine and Milrinone, with improvement of hemodynamic parameters.
The pediatric ICU stay was 96 hours and he had discharged on the 10th day after surgery, receiving medicated for CHF This procedure was performed at the São Paulo Federal University, being the first Institution in the country to adopt this procedure, and then rapidly expand to other pediatric cardiac surgery centers in the country, looking for successful results and decide to abandon the intrapulmonary tunnel (Takeushi technique)

Late postoperative follow-up
The patient had good postoperative evolution, returning for regular medical control. In October 2009, at eight years of age, the patient returned for clinical assessment: remained asymptomatic in Functional Class I (NYHA), without restriction to perform physical activities and without cardiac medication. www.intechopen.com The clinical examination showed: regular heart rhythm without murmur; ECG: normal for the age; Doppler echocardiography: preserved left ventricular function, mitral valve competence and the presence of autogenous arterial conduit and patent left coronary artery.
Computerized Tomography Angiography showed images of implantation of autogenous arterial conduit in the ascending aorta above the aortic sinus (Figure 18 a), autogenous arterial conduit patency, with uniform diameter (Figure 18 b), reconstruction of the pulmonary artery (Figure 18 c) and the presence of a significant stenosis on the left pulmonary artery not detected inprevious pre-and postoperative tests. (Figure 18 d).

Comments
ALCAPA is a rare cardiac malformation described by Bland -White -Garland in 1933 and accompanied by high mortality in infants; Vouhe et al consider the mortality of about 90% in the first year of life.
This is a congenital defect where the myocardial function was deeply compromised due to myocardial ischemia, and as it occurred in our patient, it began at 2 months of life, immediately after the closure of the patent ductus arteriosus.
The most common local of origin of the left coronary artery ostium, as in our patient, occurred in the left posterior sinus of the pulmonary valve, standing away from the ascending aorta in any attempt for direct reimplantation into the aorta. During the external examination of the heart, we observed the presence of the main coronary arteries and their branches dilated and tortuous, the result of right to left coronary shunt.
The purpose of correction of ALCAPA is to create two separate coronary systems. However, the location of the left coronary ostium near or distant from the aorta, has raised interest and stimulated the creativity of the cardiac surgeon to develop new techniques and improve outcomes in the middle and long terms.
The direct re-implantation of the left coronary artery on the ascending aorta involves the dissection and movement of the coronary artery trunk and its main branches, but tension on the sutures compromise coronary flow and result in high mortality. In our series of patients we had two deaths due to ischemic dysfunction of the LV, probably due to tension in the anastomosis after aortic implantation of the left coronary artery, which originated within the left posterior sinus of the pulmonary valve.
Aiming to avoid such incidents and to improve the operative late outcome, this technique has been modified and now employs procedures to lengthen the proximal coronary artery and permit implantation in the aorta without tension.
Thus, Sese et al in 1992 described a new technique of stretching of the coronary artery, using a flap of the pulmonary artery wall and a pedicled flap of the aortic wall; this technique was called "trap-door." The criticism of this procedure is still the need for dissection of the main branches of the coronary artery, for its approach to the ascending aorta. Nine years after the surgical correction, our patient presents good evolution and remains asymptomatic during physical activity and without medication (Functional Class I). The examinations of CT angiography, performed in December 2009, certifies the successful outcome of this technique, showing the autologous arterial graft patency and uniform diameter throughout its length.
Mitral regurgitation is a common finding in patients with ALCAPA, caused by ischemic papillary muscles and LV dilation. No case in our series had mitral valve surgery approach, being aware that after improvement of the ventricular function there would be regression of mitral valve dysfunction as documented in our patient. This conservative approach has been adopted by Vohue et al, with improvement of mitral dysfunction. This author reports that mitral valve repair is a procedure not very favorable in infants.
A recent report shows that a patient submitted to anomalous left coronary artery implanted in the aorta, followed by mitral valve repair by annuloplasty presented in the postoperative period, important mechanical hemolysis. This patient required a second intervention to remove a piece of bovine pericardium, .
Finally, the endothelized tube construction, performed in our patient, had the advantage of avoiding the use of bovine pericardial patch, employed by other authors or using the intrapulmonary tunnel technique, maintaining the patency during the late follow-up.

Hypoplastic left heart syndrome. Hybrid procedure
Despite undeniable recent improvement in survival rates, the Norwood Stage I operation for hypoplastic left heart syndrome (HLHS) and related anomalies remains a high-risk endeavor.
Neonates undergoing a stage I Norwood operation face a mortality of 10-20%,depending on the risk factors and the experience of the cardiac team. Current significant risk factors include birth weight < 2.5 kg, prematurity < 34 weeks gestational age, intact or restrictive atrial septum, additional cardiac anomalies and non-cardiac genetic malformations.
Lessons learned during the development of a novel hybrid approach have resulted in a reliable, reproducible alternative treatment for hypoplastic left heart syndrome (HLHS).
Herein we report our results using this hybrid approach in a uniform risk cohort.

Methods
This is a review of prospectively collected data on patients treated for HLHS using a hybrid approach (n = 10) between July 1995 and June 2002. The hybrid approach includes pulmonary artery bands, a ductal stent, and atrial septostomy as a neonate, without cardiopulmonary bypass. (Figure 20,21)  This patient is getting prepared for stage 2 procedure resulting in Glenn shunt physiology at six months and stage 3, Fontan completion at two years.

Results
Ten patients had a hybrid stage 1 with survival rate between 1 day and 120 days. Unfortunately, no patient completed the stage 2 and 3.
This procedure was performed by the São Paulo Federal University, being the first institution in the country to adopt this procedure, and then rapidly expanding to other pediatric cardiac surgery centers in the country, seeking successful results.
Conclusion: The hybrid approach is still acceptable due to its intermediate results, but it is not comparable to a traditional Norwood strategy. Potential advantages of the hybrid approach include the avoidance of circulatory arrest and shifting the major surgical stage to a later time. These data provide the platform for a prospective trial comparing these two surgical options to assess whether there is less cumulative impact with the hybrid approach, thereby improving end organ function, quality, and quantity of life.

Hypoplastic left heart syndrome. Palliative surgical correction with beating heart
Hypoplastic left heart syndrome is a uniformly lethal cardiac abnormality if not surgically addressed. Since the description of surgical palliation by Norwood in the early 1980s and the description of allograft cardiac transplantation by Bailey in the mid 1980s, the interest in this lesion has remarkably increased. Currently, the Norwood surgical approach consists of a series of 3 operations: the Norwood procedure (stage I), the hemi-Fontan or bidirectional Glenn procedure (stage II), and the Fontan procedure (stage III). Orthotopic heart transplantation provides an alternative therapy, with results similar to those of the staged surgical palliation. Currently, the survival rate of infants treated with these surgical approaches is similar to that of infants with other complex forms of congenital heart disease in which a 2-ventricle repair is not possible.

Norwood operation
This surgery is complex and may vary slightly depending on the diagnosis and overall condition of the heart. The main pulmonary artery is separated from the left and right portions of the pulmonary artery and joined with the upper portion of the aorta. Widening of the pulmonary artery is often necessary, and may be accomplished by using the patient's existing biological tissue or appropriate animal tissue. This allows blood, a mixture of oxygenated and deoxygenated blood to be pumped to the body via the pulmonary valve.Since the remainder of the pulmonary artery is now disconnected from the heart, one of a few techniques must be used to supply blood to the lungs:With a modified Blalock-Taussig Shunt, a Gore-Tex conduit (a kind of plastic tubing) is used to connect the subclavian artery to the pulmonary artery. In this case, blood comes from the single ventricle, through the pulmonary valve, the reconstructed aorta, the subclavian artery, and the conduit, to the lungs. There are variations on this procedure where the origin of the shunt is elsewhere in the systemic circulation (e.g. from the aorta itself) rather than the subclavian artery.

Sano modification procedure
The Sano Modification of the Norwood involves the placement of a conduit (light blue tube below) between the pulmonary artery and the right ventricle instead of the Modified Blalock-Taussig Shunt.

Sano procedure
The first operation serves to make the right ventricle the main pumping chamber for blood flow to the body. The aorta is made larger to increase blood flow to the body. A connection is made to enable the blood traveling through the aorta towards the body to "shunt" through this connection and flow into the pulmonary artery to receive oxygen. This may be accomplished with a modified Blalock-Taussig shunt, which is a small tube placed between the aorta and the pulmonary arteries or by using the Sano modification procedure, in which a homograft (tissue) conduit is placed between the right ventricle and the pulmonary arteries. The choice of which procedure is best for your child can be discussed with your cardiologist and/or cardiovascular surgeon. However, even after the stage I procedure, the infant will still have some degree of cyanosis since oxygen-poor (blue) blood from the right atrium and oxygen-rich (red) blood from the left side of the heart mixes and flows through the aorta to the body.

The Sano shunt
Over the last few years, a number of centers around the world have begun to adopt a modification of the Norwood procedure that involves a different type of shunt. Introduced by Shunji Sano, MD, who was trained in congenital cardiac surgery in Melbourne, Australia, and is now working in his home country of Japan, this new modification indicates further improvement in the survival of newborn babies with hypoplastic left heart syndrome.
The Sano shunt modification avoids the problem of competitive flow between the lungs and coronary arteries. The shunt is constructed from a slightly larger gore-tex tube graft than that used for the modified Blalock shunt. Generally a 5 mm tube graft is selected in contrast to the 3.5 mm graft used for average size babies for a Blalock shunt. Distally, the graft is connected to the main pulmonary artery between the right and left pulmonary artery takeoffs. The proximal end of the shunt is connected to a limited infundibular incision in the right ventricle.

Norwood -Sano operation at São Paulo Federal University
The Norwood procedure has been replaced by the Norwood procedure-Sano in our institution since 2004. The surgical technique consists in the careful dissection of the ascending aorta (Hypoplasia}, vessels, pulmonary trunk, pulmonary branches and ductus arteriosus. (Figure 22) www.intechopen.com The establishment of cardiopulmonary bypass was performed by anastomosis of a gore-tex tube of 4.0mm in the brachiocephalic trunk where it will be held on cerebral and coronary arteries perfusion ( fig. 23).The operation is performed with the aid of bypass and normothermic beating heart (without aortic clamping and without circulatory arrest).The perfusion of the descending aorta is performed by cannulation of the descending aorta using a Y-junction of the arterial line. Fig. 23. Surgical image. Cardiopulmonary bypass installed: arterial perfusion by gore-tex prostheses anastomosed to braquiocephalic trunk. After ductus arteriosus and pulmonary artery (PA) sectioned, the pulmonary flow reconstructed with gore-tex tub (5.0mm), anastomosed to pulmonary arteries. Ao: aorta, RPA: right pulmonary artery, DA: ductus arteriosus.
With the clamping of the aortic arch near the innominate artery, and without interfering with the coronary and cerebral blood flow, and reconstruction of the neo-aorta by interposition of segment of porcine pulmonary trunk gauge similar to the pulmonary ring, interposed between the arch and isthmus and the pulmonary trunk in the region above the valve (modified Norwood Op.) figure 24.
Finally, the pulmonary blood flow is restored through the interposition of gore-tex prosthesis of 5.0 mm or 6.0 mm, between the infundibulum of the right ventricle and the pulmonary arteries (Sano modification) Figure 25.  The results of biventricular surgical repair of congenital heart disease with obstruction of the pulmonary ventricle are satisfactory. A surgical technique started over five decades ago is closely related to adequate pulmonary valve (PV) repair and right ventricular outflow tract (RVOT) reconstruction.
The use of prostheses with no valves induced the development of valvar pulmonary insufficiency (VPI), which for many years it was considered a benign residual lesion that patients tolerated reasonably well, but this selected technique and other causes that were responsible for ventricular dysfunction are now questioned.
With the increasing duration of follow-up, however, significant late morbidity and mortality have been observed in a portion of patients More recently, the clinical relevance of VPI after enlargement of the hypoplastic pulmonary ring and trunk was confirmed once the medium and long-term results of the surgery were better known. Studies on the issue have established the need to repair the PV using valved prosthesis, minimizing or preventing VPI, which is considered to be the cause of late RV dysfunction.

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Therefore, RV diastolic function should be carefully monitored in the long-term follow-up of patients undergoing correction of: tetralogy of Fallot (TOF) with trans-annular enlargement; truncus arteriosus (TA); pulmonary atresia (PA) with ventricular septal defect (VSD); PA with intact ventricular septum (IVS) and transposition of the great arteries (TGA) + VSD + left ventricle outflow tract obstruction (LVOTO).
The Doppler-echocardiography has shown the presence of diastolic flow in the pulmonary artery, synchronized with atrial systole and the respiratory cycle. The RV diastolic volume in the postoperative recovery, determines a diastolic compliance decrease and may be detected by a continuous laminar flow in the pulmonary artery The VPI is known as one of the most important factors that cause RV dilation due to volume increase and ejection fraction decrease after surgical correction.
There is a spectrum of VPI quantified with more refined method of evaluation, utilizing magnetic resonance imaging (MRI) as well as exercise testing in the follow-up of patients submitted to operations to alleviate the pulmonary obstruction, associated with RV dilation and hypertrophy.
The development of akinetic regions and aneurysmatic dilation of the RVOT, related only in part to the trans-annular patching, is common and contributes to increase RV diastolic volumes (RVDV) and decrease RV ejection fraction (RVEF), related to the degree of VPI.
Left ventricular systolic dysfunction, aortic regurgitation and RV dilation and dysfunction exist in adults with TOF, TA, PA / VSD, TGA / VSD / LVOTO, PA / IVS etc. related to the length of palliation with arterial shunts.
Measures to maintain or restore pulmonary valve function and to avoid VPI, RVOT aneurysm or akinesia are mandatory for preserving RV and LV function late, after pulmonary ventricle repair.
This manuscript reviews our experience in 203 consecutive patients treated with RVOT remodeling utilizing a preserved porcine pulmonary prosthesis (bicuspid and trileaflet).

Study group
This study reports the surgical technique and late follow-up of the pulmonary ventricle performance and preserved porcine pulmonary prosthesis, used to PV repair and RVOT reconstruction, in patients with pulmonary ventricle obstruction.  (Figure 26).
Preoperative pulmonary hypertension, defined as pulmonary artery pressure greater than 50% of the systemic pressure was noted in 12 (5.9%) patients with TA. Cardiac catheterization was performed in 80% of the patients; more recently, MRI and computerized tomography (CT) have been used for definition of the branch pulmonary anatomy, especially in patients with PA/VSD.

Prosthesis construction
The preparation of the biological material underwent several phases for the manufacture of the prosthesis: the valve and pulmonary trunk were isolated from the swine's heart, followed by cleaning, tanning and tissue conservation.
Four different models of prosthesis were manufactured, according to the anatomical type of RV reconstruction that was programmed. These prostheses were prepared in series according to Braile-Biomédica specifications with strict Medical Quality Control. These prostheses are available commercially at Braile Biomédica and were employed for RVOT reconstruction by Pediatric Cardiovascular Surgery groups, in Brazil. (Figure 27). The pulmonary bicuspid prosthesis (PBP) was manufactured using two segments of the pulmonary artery, one including the trunk, ring and pulmonary valve and the other, only the pulmonary trunk (supravalvar area).The diameter of the pulmonary ring was measured using Hegar's dilator and the grafts were classified according to the size in millimeters. One longitudinal incision was made in the concave part, removing a slice of the wall with one of the pulmonary valve cusps. A proportional wall segment was removed from the non-valved portion.
Finally, the two structures were ligated by their proximal tips and were superposed in a 3 to 5 mm extension, with continuous anchored polypropylene 5-0 suture. The suture was started at the graft's concave face and followed the insertion of the fibromuscular ring cusp. A similar suture was performed in the convex side.
The pulmonary valved conduit (PVC) was manufactured using two entire segments of pulmonary trunk (one of these with trileaflet pulmonary valve); the tips of these segments were ligated with a running suture.
The pulmonary prosthesis with flap (PPF), was manufactured similarly to the CPP and two large flaps were performed at the pulmonary and ventricular tips.
The pulmonary prosthesis (PP) is performed by a short segment of the pulmonary artery, including the pulmonary valve www.intechopen.com

Surgical procedure
Our current strategy for RVOT remodeling utilized 4 types of preserved porcine pulmonary prosthesis: 1-Pulmonary bicuspid prosthesis (PBP) to repair the PV and RVOT reconstruction in patients under 1 year old (patients with narrow pulmonary ring and estimated pulmonary ring under 15 mm and 2-Pulmonary valved conduit (PVC): trileaflet prosthesis used in patients over 1 year old with pulmonary atresia. 3-Pulmonary prosthesis with flap (PPF) used in patients over 1 year old and hypoplastic pulmonary ring and pulmonary trunk. 4-Pulmonary Prosthesis (PP) used in patients with regular pulmonary ring or absent pulmonary valve (estimated pulmonary ring over 15 mm).
Other associated procedures for remodeling of the RV included: ventricular septal defect repair or LV to Aorta tunnel, tricuspid repair, pulmonary artery branch plastic procedure. The surgery was carried out using cardiopulmonary bypass, established with bicaval cannulation and mild hypothermia. Aortic cross-clamping with intermittent potassium cold blood cardioplegia employed for the intracardiac repair. Vacuum-assisted venous drainage routinely utilized.

Group 1: Tetralogy of fallot
The VSD was closed by right atriotomy or right ventriculotomy approach, using treated bovine pericardium patch and running suture. Relief of the RVOT obstruction was obtained by wide resection of all septum-parietal and parietal-parietal muscle bundles of the pulmonary infundibulum. In all cases where the pulmonary annulus itself seemed narrowed; the incision extended through the pulmonary annulus up to the main pulmonary artery and the whole area was primary or reoperation; were performed with the heart beating.
For the reconstruction of the pulmonary ventricle in patients under 1 year old, a PBP was implanted and adjusted to the rudimentary pulmonary valve of the patient. (Figure 28).
In patients over 1 year old, a PPF (trileaflet pulmonary valve) was implanted in the native pulmonary annulus with running suture. For the reconstruction of the pulmonary trunk and RV outlet tract, two flaps (pulmonary and ventricular flap) of this prosthesis were used.
www.intechopen.com Measurements were obtained by visualizing the heart images (including the prosthesis for the insertion of valves) and comparing them with the catheter's diameter in a superposed graded film with the identical magnification.
During the operation, the diameter of the pulmonary annulus was determined by classic normogram. The size graft was chosen according to the patient's weight: less than 10 kg, it was used 8 to 10 mm; and over 10 kg, it was used 12 to 20 mm.
In the cases with pulmonary atresia or absent pulmonary valve and under 1 year of age, a new cuspid was constructed using tissue from the pulmonary artery posterior wall, providing support for the PBP.
In patients over 2 years of age, the pulmonary valve and RVOT was reconstructed with porcine pulmonary prosthesis (Figure 29 a,b) In cases with anomalous origin of coronary artery, crossing the infundibulum, the remodeling right ventricle surgery was performed with porcine pulmonary valved conduit. (Figure 30)

Group 2: Pulmonary atresia with ventricular septal defect
In this group, all thirty two (15.7%) patients were over 14 month of age. There were 3 cases with aortic-pulmonary collateral arteries submitted to previous unifocalization surgery plus Blalock-Taussig shunt. (Figure 31 a,b) The surgical approach was performed by right ventriculotomy, after resection of the infundibulum muscle and closure of the VSD and finally was performed the right ventricle www.intechopen.com remodeling surgery, implanting a porcine pulmonary valved conduit, between right ventricle infundibulum and pulmonary artery Fig. 29. Surgical photography. a-Patients with tetralogy of Fallot and absent pulmonary valve (arrow). b-Right ventricle (RV) remodeling with porcine pulmonary prosthesis (PPP) (arrow) (in detail)

Group 3: Truncus arteriosus
In this group, 12 (5.9%) patients under 6 months with TA type I, II were operated.
During the surgical approach, the pulmonary artery was disconnected from the ascending aorta and the left aortic sinus was reconstructed using a bovine pericardium patch; by the right ventricle approach, the VSD was closed, connecting the LV to the Aortic rout.
In ten patients, the posterior wall of RVOT was constructed with a pulmonary flap of the left pulmonary artery, but we did not use a monocuspid patch, according to the author`s technical specifications.
For the reconstruction of the pulmonary ventricle, we adjusted to the neo pulmonary annulus a PBP. In the remaining 2 patients, PVC was used for the reconstruction of the RVOT. PBP implantation was a surgical alternative for correcting TA type I and type II at early age (<6 months) using the technique without conduit.

Group 4: Transposition of the great arteries with pulmonary stenosis
Eight (3.9%) patients of this group, age ranging from 2 to 8 years old (mean= 3.0), had TGA, VSD and left ventricle outflow tract obstruction (LVOTO) (Fig 32 a).
The Lecompte technique was performed in all our cases, and consists in approaching the upper right ventriculotomy, extensive resection of the conal septum and enlargement of the VSD. Afterwards, with a pericardium or Polytetrafluoroethylene (PTFE) patch and running suture, a tunnel was performed connecting the left ventricle to the aortic route (LV-Ao). (Figure 32 b) Later, the aorta and the pulmonary artery were sectioned, the pulmonary valve was closed, the Lecompte maneuver was performed and finally the aortic and pulmonary outflow tracts were reconstructed.
In 6 cases a porcine pulmonary prosthesis with flap was used for the RVOT reconstruction (Figure 32 c) and porcine pulmonary conduit , in 2 remaining cases. One patient who had been submitted to Rastelli procedure 3 years earlier, presented RV-PA prosthesis obstruction and severe RV failure. This case was operated in emergency state and converted to Lecompte operation: After aortic section, the Lecompte's maneuver was performed and the pulmonary artery was positioned in front of the aorta. A PBP was used for RVOT reconstruction. www.intechopen.com

Group 5: Pulmonary atresia with intact ventricular septum
Seven (3.4%) patients of this group, with ages between 1 and 12 years old (mean= 4.0), had pulmonary atresia with intact ventricular septum (PA/IVS). Three patients had the first stage of the operation (Blalock-Taussig shunt plus pulmonary valvotomy) performed in neonatal period and second stage (Glenn operation) at 1 year old .
In these patients a "normal" tricuspid valve (Z score more than -4.0) and hypoplastic but potentially usable right ventricle was observed. The repair consisted in patch closure of the atrial septal defect, tricuspid valve plastic repair and reconstruction of the RVOT was performed with PBP (One and a half ventricle repair with pulsate bidirectional Glenn) ( Figure 33) The remaining 4 patients had pulmonary valvotomy in neonatal period. The tricuspid valve and RV had morphology, size and function near normality. In these patients it was implanted a PPF to reconstruct the RVOT.

Surgical recuperation
In all patients it was employed conventional ultrafiltration (CUF) during cardiopulmonary bypass (CPB) and in the last 12 years, modified ultrafiltration (MUF), after CPB was associated.
It was possible to discontinue CPB, in all cases and no patient had delayed sternum closure.
Sinus rhythm was maintained in all patients, before discharge from hospital. Temporary cardiac arrhythmias were detected, in 10 % of the cases, during hospital stay. No pacemaker was indicated or implanted in this group.
The most frequent cardiopulmonary support was performed with Dobutamine and Milrinone drugs.

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There were 4 late deaths (2.1%): Two patients with TOF, caused by cardiac arrhythmia and bacterial endocarditis. Other two patients, with TA and PA/VSD, caused by ventricular dysfunction.
In three patients it was detected residual pulmonary branch stenosis.

Reintervention
Seventeen (9.6%) cases were submitted to reoperation due to residual defects or prosthesis dysfunction in an interval of 24 to 120 months after operation. Two patients developed aneurysmatic dilatation of the pulmonary prosthesis: after TOF correction and after "One and half ventricle" correction. Both patients died after reoperation due to ventricle dysfunction and surgical bleeding.
The pathologic study of the prosthesis removed shows: calcification islands compromising the external wall but preserving the integrity of its leaflet; nevertheless, two cases with aneurysmatic dilatation show sling wall and no presence of calcification. (Imperfection tissue fixation?).
Two patients presented residual pulmonary stenosis, located at the right and left branch origin. Both cases required placement of pulmonary stent implant.

Follow-up
Reconstruction of the PV and remodeling of the RV was an essential component in the treatment of many patients with congenital heart disease.
Fourteen patients (7.9%) were lost during the follow-up. One hundred and sixty two (79.8%) surviving patients were followed from 4 to 204 months (mean= 108). Actuarial survival curve at 204 month was estimated in 86.6%. (Figure 34) The follow-up of these patients included: Clinical exam, exercise stress test, metabolic stress test, Doppler echocardiography study, Hemodynamic study, MRI and CT study.
We do not have all the complete data set on all of the above variables for the entire cohort of patients in this manuscript.

Doppler echocardiography study
This was the most frequent auxiliary study employed to analyze the results of cardiac surgery and prosthesis performance. This study was performed twice a year, during the follow-up. With the echocardiogram many parameters of the RV function were studied: RV performance, RV dimensions; and with the Doppler index: if tricuspid regurgitation (TR) is present an estimate of RV pressures, RV-PA gradients and pulmonary and tricuspid valves function. One hundred and forty three surviving patients were discharged from hospital with RV-PA gradient less than 30.0 mmHg and trivial to moderated VPI. During the follow-up, in ten patients the Doppler-echocardiogram was decisive for reoperation and in other two patients, for the indication of hemodynamic procedure.
Among the 162 (79.8%) regular late follow-up patients, the degree of VPI that increased slightly was detected in 20 patients (12.3%), but only one patient had important pulmonary regurgitation

Hemodynamic evaluation
Hemodynamic studies were carried out in the first 15 (9.2%) cases of 162 survival patients with regular follow-up. All 15 patients had TOF and follow-up between 48 and 87 months (mean= 65.1). The patients age ranged from 5 to 16 years (mean= 8.2 years).  The measurements were obtained by visualization of the heart images (including the prosthesis for the insertion of valves) and superposed in a graded film with identical magnification which was compared to the catheter's diameter.
In some cases it was difficult to establish the position of the pulmonary ring due to the presence of RVOT prosthesis. The degree of VPI was evaluated by the quantitative method after injection of contrast solution in the pulmonary artery, and the VPI was classified as mild when regurgitation was lower than 50% (group A) and moderate when greater than 50% (group B).

Hemodynamic dates
Out of fifteen patients undergoing hemodynamic and angiocardiographyc evaluation, no residual blood flow from left to right ventricular camera or significant gradient between the RV and PA was observed.

Magnetic Resonance Imaging and Computerized Tomography study of the heart
Cardiac MRI and CT study has become an available method of diagnostic and postoperative follow-up. (Fig 35, 36) In order to assess the responses of PV reconstruction and remodeling of the RV with PBP or PPF, it was used CT imaging and PVI evaluation and biventricular function using a MRI in patients who underwent TOF, PA / VSD, AT, TGA / VSD / LVOTO and PA/IVS repair.
In 2006, 10 patients were submitted to MRI and CT study with follow-up over 10 years. The parameter of cardiac function was obtained at rest: RV ejection fraction was normal (>45%) in 8 (80%) patients, the MRI was well suited to assess cardiac response and findings revealed a discrete VPI in PBP and a trivial VPI in PPF.

Statistical analysis
Statistical analyses of continuous variables were performed with both methods: by paired t test and the analysis of categorical variables performed by the Student's t test and p<0.05.was considered statistically significant. The surviving patients curve was prepared according to the Kaplan-Meier's method, comparing 2 or more functions by the long-rank test. For all tests, a p value of less than 0.05 was considered significant.

Comments
The patients undergoing TOF repair surgery have an excellent prognosis and good late survival in about 90% of the cases, ten years after the surgery. In 95% of the cases it is possible the patient's social reintegration and good physical ability during exercise and 79.3% practice sports. 20 Reconstruction of the PV and remodeling of the RV using valved prostheses is an essential component in the treatment of patients with TOF and others congenital heart diseases with pulmonary ventricle obstruction.
It is difficult to establish the number of patients who had surgical correction of TOF and required reoperation. In general, it depends on the anatomical lesion of each patient and the kind of surgical approach used, as well as the kind of surgical reconstruction employed.
Multiple surgical options for PV reconstruction are available for these patients: mechanical valves, mechanical conduits, monocuspid homograft or patch, pulmonary and aortic homograft, stented and stentless heterograft, heterograft conduits, bovine jugular vein conduits and autologous pericardial valves.
The use of a mechanical valve in the pulmonary position has been reported in a few patients and had fallen out, due to frequent occurrence of thromboembolic phenomena and valve failure In 1967, Marchand introduced a monocuspid homograft with excellent results. This type of RVOT repair was very well accepted and routinely adopted in several services, however, the presence of diastolic murmur and the early postoperative evaluation found out that different degrees of pulmonary insufficiency were interpreted as an inadequate alignment of the leaflet graft with the pulmonary valve native leaflets in the early postoperative followup.In 1968 Asano & Eguchi published their clinical experience with the use of a bicuspid pulmonary homograft and bicuspid pulmonary heterograft. An autologous pericardial segment sutured to pulmonary ring was used for the reconstruction of the RVOT. A posterior author's (publication28) performed, described aneurismal dilatation of autologous pericardial segment at late follow-up.
Therefore, when the enlargement of the pulmonary ring is strictly necessary, the use of open tile-shaped prosthesis, in patients under one year old, allowed the ring to grow at the expense of the posterior wall. On the other hand, once this is a valved prosthesis adjusted for the right closure at the time of the operation, the growth of the pulmonary ring might make the prosthesis less contingent. On the other hand, the growth of the native valve might also be expected, although it can hardly be clinically proven.
A larger experience with PTFE monocuspid for RVOT reconstruction in 115 patients with follow-up of 6 months to 8 years (mean=2.6), demonstrated significant development of VPI graded as moderate to severe after 35 months in this monocuspid study.
Homograft valves have become widely used for reconstruction of the right ventricular outflow tract in congenital heart disease. However, mid-term and long-term follow-up studies have clearly demonstrated conduit obstruction and early valve insufficiency, degeneration and progressive calcification, more frequent in aortic homograft.
Some authors suggest that possibly the durability of cryopreserved pulmonary homograft is similar to pulmonary homograft used for the Ross procedure. When the trileaflet prosthesis is implanted in the orthotopic position, as in the Ross aortic valve replacement patient, can be easily accommodated, maintaining valvar competence.
The limited durability of homograft conduits, especially in small sizes, supported the search for an alternative conduit as the PBP, bicuspid homograft and PTFE bicuspid valve, that allowed the growth of the posterior face of the pulmonary ring and posterior wall of the pulmonary trunk. The superiority of the bicuspid prostheses has been demonstrated in experimental studies for reconstruction of a hypoplastic pulmonary root, and this experience was confirmed in clinical experience.
Pulmonary valve insufficiency may have a negative impact on RV function leading to the need for reoperation for the insertion of a competent valve at the RVOT.
There are no ideal options for restoring the VPI. Studies including adult patients with TOF after pulmonary valve replacement with various prostheses, generally reported good longterm results with both porcine xenograft and homograft.
www.intechopen.com VSD or PS might impair the long-term results and significantly change the patient's prognosis. Beginning in 1991, we started to use a preserved PBP in infants and PPF in children for the reconstruction of PV and RVOT in patients with TOF aiming to decrease residual VPI.
This series of patients undergoing TOF repair surgery presented an excellent prognosis and good late survival rate in about 80% of the cases, seventeen years after the surgery. 78% of the surviving patients, with late follow-up, are free of reoperation and show good physical ability during exercise and practice of sports. The hemodynamic evaluation of these patients shows that average individual RV/LV length ratios did not increase over time.
Although the preliminary studies of a valved bovine jugular vein conduits had reported short to intermediate term durability, Boudjemline et al and Zavanella et al, reported similar findings of extensive fibrosis at the conduit pulmonary anastomosis by developing intimal proliferation.
In these patients, submitted to PPF implantation, a technical modification was introduced to reduce PS development by intimal proliferation at the conduit: It was performed an enlarged pulmonary anastomosis, after constructing a flap at the distal graft's tip.
This procedure was also used for the reconstruction of pulmonary ventricular outflow tract in another group of patients: PA / VSD, AT, PA / IVS, TGA / VSD / LVOTO.
In the PA/VSD group, all patients were over 14 months of age and only 18 cases had palliative procedure, type: Blalock-Taussig shunt and unifocalization procedure.
All patients were submitted to pulmonary arteriography; in order to study the diameter of the PA (trunk, right and left branches) it was determined the McGoon index. Although, other quantitative methods were employed to study the degree of pulmonary development, in order to measure the pulmonary area, it was determined the Nakata index or PA index (PAI). All patients of our series had PAI higher than 150 mm/m 2 .
During the operation, it was possible to close the VSD in all patients and after cardiopulmonary bypass, the RV/LV ratio pressure was measured; in all cases this relationship was below 0.58%. Total deaths: one patient died after refractory low cardiac output and another by generalized infection.
In the AT group, two types of prostheses were used for the reconstruction of the PV and remodeling of the RVOT: The implant of the PBP was a surgical alternative for the correction of the AT type I, II, at early age (under 6 months), using the technique without conduit. In 8 patients of our series, it was possible to use the RVOT reconstruction using a bicuspid prosthesis: Using a flap of the left pulmonary it was constructed the posterior wall of the RVOT and using one PBP and running suture this prosthesis was adjusted There were two hospital deaths by pulmonary hypertension crises.
The PVI was trivial in all cases, at the immediate postoperative period, in 7 surviving patients. At this moment, no patient was submitted to re-intervention, but actually 3 patients are in functional class II (NYHA) and presented moderate VPI.
2 -In the second type of prosthesis, the PP was implanted in patients older than 6 months. Two patients underwent operation with this technique: One patient, who underwent operation with a valveless woven Dacron conduit 5 years earlier in another center for RV dysfunction with significant PVI, received a PP implant.
The pulmonary ventricle may be compromised by either morphologic or functional problems, or by both. The morphologic defect may be defined by tricuspid valve Z value. In general, this value also reflects the corresponding ventricle volume.
Right ventricle outflow tract is alleviated by a variety of techniques, including muscle resection, valvotomy with division of the pulmonary annulus along with the commissure and reconstruction of the RVOT with a trans-annular pericardial patch or biological valved prosthesis.
In our series, seven patients with PA /IVS were submitted to correction with "one and half ventricle" technique, with success. All cases had Glenn procedure previous and were performed with the same procedure: atrial septal defect (ASD) closure and reconstruction of the RVOT with PPF. One patient was submitted to trans-catheter closure of the residual Blalock-Taussig shunt. The right ventricle performance and RV -PA junction were evaluated with MRI and the RVOT reconstruction with CT study. (Fig 8 A,B) The gradient RV -PA in all three patients was lower than 30 mmHg.
The Lecompte 51 procedure introduced for the treatment of TGA / VSD / LVOTO, consisted in the construction of a LV to Ao tunnel, after conal septum resection, by ventricle approach. The RVOT reconstruction is performed after the pulmonary artery is transferred in front of aorta (Lecompte maneuver). A valved prosthesis is employed for the pulmonary valve reconstruction. This technique is called the REV procedure.
For the reconstruction of the pulmonary outflow tract there are two techniques: When the aorta and the pulmonary artery are in anteroposterior position, the reconstruction of the RVOT is possible, after transversal aorta and pulmonary artery section and pulmonary valve reconstruction in front of the aorta.
When the aorta and the pulmonary artery are in side by side position, the Lecompte maneuver is dispensed and a valved conduit is necessary to reconstruct the pulmonary outflow tract.
In our series, when the great arteries had an anteroposterior relationship, it was not difficult to pull the pulmonary artery down to the right ventriculotomy site without tension in order to reconstruct the pulmonary outflow with a PBP. However, when the pulmonary artery and the aorta were in side by side position, the Lecompte maneuver was also employed and the pulmonary outflow tract was reconstructed with PPP.

Conclusion
The clinical follow-up of 176 (86.6%) patients from 4 to 204 months (mean=108) allowed the following conclusions: Right ventricle remodeling constitutes a safe and standardized technique.
The early reconstruction of the pulmonary valve and right ventricle outlet tract could be able to preserve ventricular performance for a long period.
The prosthesis function could be analyzed during the follow-up.
The porcine pulmonary prosthesis has shown satisfactory results for a long time.

New technique in Cardiopulmonary bypass
9.1 Conventional and Modified Ultrafiltration during cardiac surgery in high-risk congenital heart disease.
The use of cardiopulmonary bypass (CPB), with hypothermia and hemodilution, in the pediatric age group is associated with the accumulation of an excessive amount of water. The ratio of prime volume to patient blood volume may be twice as high in smaller patients. However the inflammatory capillary leak is probably responsible for tissue edema and malfunction of several organs. Dilution of plasma proteins increases water transfer to the extravascular compartment and postoperative blood loss as a result of clotting disturbances.
Several methods are in use in order to reduce this water accumulation such as reduction of circuit diameter and prime volume, anti-inflammatory therapy, continuous diuretic and peritoneal dialysis. In 1991, Elliott's group from The Hospital for Sick Children at Great Ormond Street (London), reports an alternative technique of modified ultrafiltration (MUF) after CPB, through a filter with semi-permeable membrane, to remove water, electrolytes and other low molecular weight substances.
Conventional ultrafiltration (CUF), performed during CPB is associated with a statistically significant prime ultrafiltration but with clinically poor results.
Early studies with CPB in children demonstrated clinical improvement due to inflammatory agent removal, including endothelin-1 (a potent pulmonary vasoconstrictor) and other cytokines released during the warming period of CPB.
Efforts to reduce the detrimental effects of the capillary leak syndrome after CPB include ultrafiltration during CPB.
This prospective study was therefore undertaken to compare the effects of CUF + MUF with those of CUF during surgery for congenital heart disease.

Patients and methods
Forty-one children with complex congenital heart disease who underwent operations using CPB at Cardiovascular Division of the São Paulo Federal University .
Our service is the first service in the country in implementing this technique. To day, the MUF is used routinely in all patients submitted to surgery with CPB Patients operated between January 1996 and March 1998 were included in this study. The Ethics Committee of the Institution approved the study protocol and informed consent was obtained from the parents of each child.

Patient group
This was a prospective, consecutive and nonrandomized study. We assigned 41 patients to one of two groups as follows: control group (n = 21) in which CUF during CPB was used.
Pediatric cardiac surgeries were performed between January 1996 and April 1997 (CUF group); and the experimental group (n = 20) in which CUF was associated with MUF after CPB, with surgeries performed between May 1997 and March 1998 (CUF + MUF group) The patient characteristics are shown in Table 8. Both groups included patients with ages between 9 and 36 months. These groups were homogeneous and no significant differences were observed between them. CUF: conventional ultrafiltration; CUF+MUF: modified ultrafiltration; mo.: months Table 8

Preoperative evaluation
Preoperative evaluation was performed by cardiac catheterization in all patients with moderate and severe pulmonary hypertension (PH), using a 40-biplane angioscope (Siemens). Preoperative PH was defined as a systolic pulmonary pressure/systolic systemic pressure > 60. PH was present in 15 patients (71.4%) of the CUF group and in 14 patients (70.0%) of the CUF + MUF group.
Transthoracic Doppler echocardiography was performed in the patients using ATL Ultramark 9 with a 3-5 MHz transducer.

Surgical technique
Surgical management was standardized by cannulation of the ascending aorta for inflow, separate caval cannulae being inserted through the right atrium. CPB was instituted after 400 U/kg heparin infusion. A flow rate of 2.4 l/min/m2 at normothermia was reduced to 1.8 l/min/m2 during moderate hypothermia (25°C to 28°C).
Deep hypothermia (< 24°C) and circulatory arrest were not required. The left side of the heart was vented with a catheter inserted in the apex through the right upper pulmonary vein.
The pump prime was composed of 500 to 900 ml electrolyte solution with 5% glucose (Darrow Imagem S/A, Brazil), sodium bicarbonate 10 to 30 mEq/l, 25% albumin (12.4 g/250 ml of prime), 2% mannitol 2.0 ml/kg and washed packed red blood cells to maintain a hematocrit value of 25%. Partial arterial pressure of carbon dioxide was recorded. The infusion of blood cardioplegic solution was repeated at 20-minute intervals.

Technique of conventional ultrafiltration
In the CUF group, patients were treated with ultrafiltration during CPB, at the warming stage, which removed excess fluid and hemoconcentrated the patient's blood. A hemoconcentrator (model HPH 400,Minntech,Minneapolis,MN) was also inserted in parallel in the cardioplegic line (connected to the recirculation line).
The total amount of fluid filtered by CUF was 19.7 ml/kg. After CPB, blood from the extracorporeal circuit was centrifuged for red cell salvage.

Modified ultrafiltration technique
The MUF group was submitted to the CUF procedure during CPB and then an arteriovenous ultrafiltration via the cardioplegia circuit was used according to Groom's technique, with some adjustments introduced in the system (Fig. 38).
Following the last dose of cardioplegia, the hemofilter is placed in the cardioplegia circuit after the cardioplegia (sucker) roller pump but before the heat exchanger. The cardioplegia line is clamped and CPB is discontinued but the heparin is not reverted.
The venous cannulae are removed from the right atrium and the blood within the venous line is siphoned into the venous reservoir. The clamp on the arterial filter bypass line is removed and placed just prior to the filter. A 10 F to 12 F cannula is attached to the cardioplegia line and placed in the atrium. The cardioplegia pump is turned on and the flow is slowly increased.

Fig. 38. Modified Ultrafiltration Circuit
This maneuver pumps blood from the aorta through the hemofilter and cardioplegia system and then Returns, the warm blood, to the RA after passing through the heat exange of the cardioplegia line.
When the target flow of 100 to 200 ml/min is reached, the clamp of the filtrate line is removed, allowing the ultrafiltration process to begin. No suction was applied to the filtrate line. As plasma water is removed, it is necessary to maintain the patient's volemic status by transfusing the content of the pump circuit at a rate equal to the filtration rate.
After this process continues for approximately ten minutes, the cannulae are removed and protamine is administered. The total amount of fluid filtered by conventional and modified ultrafiltration in this group was 39.3 ml/kg.

Intraoperative monitoring
Left atrial catheter was used in all patients and pulmonary arterial catheter was used inpatients with preoperative PH. When the systolic pulmonary artery pressure was higher than 40 mmHg, nitroprusside at a dose of 0.5 to 1.5 µg/kg/min, or nitroglycerin at a dose of 1 to 10 µg/kg/min was used.
If dobutamine or dopamine was required, a dose of 5 to 10 µg/kg/min was used; or in the case of epinephrine, a dose of 1 µg/kg/min.

Postoperative pulmonary hypertension control
Patients with preoperative PH were curarized and moderate hyperventilation was used. These patients also received nitroprusside, nitroglycerin and nitric oxide.

Postoperative management
All patients were followed-up in the Pediatric Intensive Care Unit (PICU).

Strategy for extubation
The respiratory management consisted of mechanical ventilation support to maintain the arterial oxygen tension at > 100 mmHg, the arterial carbon dioxide tension at 30 to 35 mmHg and the pH at 7.45 to 7.50. Once the children exhibited hemodynamic stability, they were weaned from mechanical ventilatory support and sedation.
Once the children demonstrated the ability to sustain adequate spontaneous respiration effort and required minimal supplemental oxygen as reflected by normal arterial blood gases, they were extubated. Neonatal patients at high-risk for post-operative PH required longer ventilatory support. Strategy for blood or hemoderivate replacement No patient in this study received aprotinin. Washed packed cells were transfused to maintain hematocrit at 40% for patients with cyanotic congenital heart disease and 35% for those without cyanotic heart disease. Platelets, fresh frozen plasma, cryoprecipitate and albumin were transfused as required postoperatively.

Statistical analysis
Comparison between the two groups regarding duration of ventilator support, PICU stay and hospital stay data was performed by means of Student's t test.
Repeated measures analysis of variance was employed to evaluate the two groups during pre-and perioperative periods regarding hematocrit and platelet counts.
The hospital discharge probability was estimated using the Kaplan-Meier method. The logrank test was employed to compare the two groups.

Operative outcome
There were no MUF related complications. In all the patients it was possible to close the chest. No patient required reexploration for bleeding.
There were four postoperative deaths in the CUF + MUF group. All patients had PH and the main causes were cardiac arrhythmia, low cardiac output, ventilation problems, vasoactive agent handling and pulmonary infection.
There were six postoperative deaths in the CUF group. Five patients had PH and the main cause were coagulopathy, low cardiac output, ventilation problems, vasoactive agent handling and pulmonary infection.

Duration of ventilator support
Mean and standard deviation of duration of ventilator support in surviving patients of the CUF group were 94.8± 66.20 h for the CUF group and 95.67 ± 90.29 h, and for the CUF+MUF group. No significant difference was observed between the two groups (p= 0.976) Table 9.

PICU stay
Mean and standard deviation of the time of PICU stay in surviving patients of the CUF group were 169.60 ± 90.61 h and 157.81 ± 150.80 h for the CUF+MUF group. No significant difference was observed between PH groups (p= 0.795) Table II.

Hospital stay
The time of hospital stay in surviving patients of the CUF group were 14.87 ± 5.57 days and in surviving patients of the CUF+MUF group it was 14.69 ± 9.67 days. No significant difference was observed between PH groups (p= 0.950) ( Table II). The estimated probability discharge from hospital after the 15th postoperative (PO) day was approximately 85% for both groups (Fig. 39 Table 9. Comparative results regarding studies variables of the CUF and CUF+MUF groups.

Blood transfusion
The CUF group presented significantly higher values of hematocrit than the CUF+MUF groups at the different times during the perioperative periods (p= 0.032). A significant decrease was observed after the surgery (p= 0.037), mainly in the CUF+MUF group.
The analysis of platelet counts at the different times during the perioperative period. There were no significant differences between groups (p= 0.673). A significant decrease was observed in platelet counts after the surgery (p< 0.001).
Requirements for red blood cell and coagulation factors (platelet, fresh frozen plasma and cryoprecipitate) were similar in both groups.
Only 15.8% of the CUF group (3 of 21) did not require red blood cell transfusion, whereas 16.7% patients (3 of 20) in the CUF+MUF group were free of red blood cell transfusion.

Discussion
Surgical correction of complex congenital heart disease in children requires long times of CPB and moderate or deep hypothermia inducing water retention, hypervolemia and distribution of liquid in the extravascular compartment. On the other hand, the generalized inflammatory reaction due to protein mediator release contributes to increase in capillary permeability and tissular edema, impairing organs such as the heart, lung and brain.
Accumulation of body water occurs due to intravenous administration of solutions and the contact of the prime with the patient's blood. On the other hand, CPB induces a generalized inflammatory reaction with unbalance of the patient's internal environment, increasing body water retention. These effects have a greater impact in low weight children who require correction of complex heart defects.
Based on studies of ultrafiltration in adult's, in 1990 we started to use CUF in children during the warming stage of CPB with satisfactory results. The purpose of CUF was: removal of excess water from the priming of the CPB and hemoconcentration of erythrocytes and coagulation factors increasing hematocrit, decreasing bleeding in the postoperative period, thus reducing the need for transfusions of the patient.
Introduction of MUF, after CPB, has avoided excessive accumulation of body water and improving the patient's clinical conditions, allowed decrease in bleeding and reduction of blood replacement and ultrafiltration of protein mediators responsible for the inflammatory response, aiming at PH control, reduction in time of use of vasoactive drugs, of pulmonary ventilation and of hospitalization.
In this study, 20 patients below the age of 36 months, who on surgical correction were submitted to the association of ultrafiltration methods (CUF + MUF) with follow-up until discharge from hospital, were compared to a similarly operated group previously and submitted to CUF. Therefore this is a comparative, prospective and consecutive, nonrandomized study like others in the literature.
Randomization of patients undoubtedly represents an ideal situation because it allows an accurate evaluation of the results, as shown by other studies on this subject. However, other comparative studies present restrictions to the evaluation of the benefits of MUF use.
Studies, equal to the present, one comparing CUF + MUF with CUF in two similar groups of pediatric patients, have been carried out by other authors.
The design of our research offered equal ultrafiltration opportunity to both groups, whose age, weight surgical complexity profile characterized them as being at high risk. All patients received CUF, thus allowing ultrafiltration of inflammatory reaction mediators primarily released during the warming stage of CPB.
Initially the MUF technique we used was similar to that presented by Elliott. However, due to the need to keep the ultrafiltered blood returning to the right atrium warm, as in Groom's study, we introduced changes in the outlet of the hemoconcentrator, substituting it for the cardioplegia line and thus allowing passage of ultrafiltered blood through the heat exchange.
Use of MUF after CPB, allows improvement in the systolic function of the left ventricle (LV) in children submitted to correction of congenital defects. There is an increase in the final diastolic diameter and fall in final diastol i c p r e s s u r e o f t h e L V a f t e r M U F d u e t o improvement in ventricular compliance, as a result of the reduction of myocardial edema. The hemodynamic improvement could be related to this reduction and the neutralization of the inflammatory response because of ultrafiltration of protein mediators.
Interest in the use of the MUF technique, benefits to the patients and possible intercurrences are increasing and justifying further studies by multiple centers. Despite the acquired experience, technical complications, which should not be discarded, have been detected.
The need for the evaluation of results in children at high surgical risk has led us to define our research in children aged 0 to 36 months, as has been done by other studies.

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Patients submitted to prolonged CPB, hemodilution and hypothermia might develop a substantial myocardial edema, making chest closing difficult if they are not adequately ultrafiltered . In our study all patients were led to the PICU with a closed chest.
In spite of the significant hemodynamic improvement through the use of CUF + MUF in our study, as well as in others, no significant differences were found regarding number and time of use of inotropic drugs when compared with the control group.
Reduction in pulmonary ventilation time and time of stay in the PICU is evident with use of MUF, although in our study no significant difference has been found.
There was a proportional fall in the Ht of both groups during the postoperative period and, according to the established criteria to maintain the Ht at 35% in acyanotic children and at 40% in cyanotic children, 84.2% of the patients of the CUF group and 83.3% of the patients of the CUF + MUF group, received blood, but there was no statistically significant difference between the groups.
Classification of the patients according to the degree of surgical complexity allowed the analysis of impact of hospital mortality in relation to the different variables. Despite the fact that there was no statistically significant difference regarding degree of complexity of the CUF and CUF + MUF groups, there were 50% of the CUF + MUF patients in category 3 and 4 (more severe) while in the CUF group, 76.2% of the cases belonged to category 2 (less severe).
Regarding duration of hospital stay, there was no significant difference between the groups, analyzed at 5 different times, 90% of the patients of both groups being discharged from hospital on the 20th day of postoperative period. Duration of hospital stay of patients submitted to surgical correction of complex congenital heart disease is usually prolonged, significantly increasing hospital costs. A detailed analysis of treatment time in this group of patients submitted to ultrafiltration will allow the assessment of reduction in hospital costs.
Association of congenital cardiopathies with severe PH (ratio pulmonary pressure/systemic pressure > 60%) represents a group at higher surgical risk requiring effective treatment for PH control. The PH associated with high pulmonary vascular resistance is responsible for the long periods of mechanical ventilation, stay in PICU and high morbidity and mortality, after correction of cardiac defects using CPB.
Endothelin-1 produced by the cells of the vascular endothelium is a vasoactive agent, which participates, in the pathophysiological mechanism of PH. Studies have shown that the use of total hemodilution during CPB, associated with MUF, in children submitted to correction of cardiac malformations and PH, allow the elimination of excess body water and ultrafiltration of endothelin-1.
In our study, in the CUF + MUF group, consisting of 20 patients, 14 (70%) presented PH and in the CUF group, consisting of 21 patients, 15 (71.4%) had PH.
Despite the tendency to improvement of the results in the CUF + MUF group, there were 4/20 deaths (20%) as compared to the CUF group with 6/21 (28.5%) deaths. www.intechopen.com

Conclusion
We obtained those of Groom's group, a circuit design using cardioplegia line, have shown to be safe and equally efficient, with a significant filtered volume in the CUF + MUF group.
Probably the efficacy of the CUF used in all patients and the lack of adjustment of the preoperative care protocol did not allow establishing more consistent results in the studied groups. These results should be examined with caution because they refer to a nonrandomized group with a small number of patients with high-risk congenital heart disease.
Currently we routinely use CUF + MUF in all pediatric patients undergoing heart surgery in our Institution. With ultrafiltration methods, in the future, pediatric patients should equally benefit from controlling their water balance, neutralizing the inflammatory response and reducing transfusion volumes.

Pediatric cardiac surgery as a philanthropic activity in the country and foreign humanitarian mission
In Brazil each year are born 30,000 new patients with congenital heart disease, 50% of which need surgical correction in the first year of life. The statistics show data that are published yearly by Associação Nacional de Saúde (ANS) of Brazil, that only 6,000 -7,000 patients undergo cardiac corrective or palliative surgery each year. These figures do not include the patients holding health insurance operated in hospitals associated to the medical insurance network; although it is a small contingent.
This reality shows that due to the fast technological development process in Medicine, the particularity of each patient was completely disregarded and his illness became an object of scientific study. The medical procedures, therefore, became inhuman.
In the same process, some changes have occurred in medicine graduation and in the work conditions, increasingly specialized, restricting the availability of physicians either for contact with the patient or for the search of a more specialized formation.
The actual conditions of medicine practice have not contributed to the betterment in the relationship between physicians and patients, and for a humanized assistance with good quality (this applies for both professionals in the area and health care institutions).
Nowadays, several actions have been proposed aiming the implementation of humanizing programs in health institutions, especially in pediatric assistance in hospitals; several projects and actions develop activities associated with plastic arts, music, theater, leisure and entertainment.
There are some Institutions that claim to be already humanized, but in some cases, this humanization applies only to architectural improvements and medical assistance aiming fiscal benefits. Undoubtedly, these are relevant measures in an Institution; however, they can be merely superficial factors unless they are inserted in a vast process of Humanizing Institutional Relationships.
When pondering about the Assistance Duties it can also lead us to Ethics. The ethic matters appear when one worries about the consequences of his actions upon others. www.intechopen.com The work of a professional, whatever his activity might be, depends on both technical quality and interaction quality. In medicine, quality is a must that makes each specialty aim to develop its technical capacity that is part of what it is called relative abilities and knowledge of the technical area. In order to internationally capacitate the physician, of any specialty, it becomes necessary the instrumentalization to recognize and deal with the emotional aspects of assistance, that is, developing attitude.
Humanization is a vast, slow and complex process to which many definitely offer some resistance, because it involves changes of behavior that often promote insecurity. The already established standards seem rather safer, in addition, the new ones are not currently legal and do not have general characteristics, because each professional, each institution has its own particular humanization process. In this process many instances must be involved: Professionals of all areas, Institution Directory Board, politicians and public attorneys, a Professional Counsel and Philanthropic Entities.
There are a few public and private hospitals, in the country, that offer conditions for a complete assistance to children, in order to perform high complexity procedures.
Therefore, the pediatric assistance fails to meet the special needs of patients due to the long lines in ERs, shortage of vacancies in nurseries, ICU, etc; on the other hand, children that need to be transferred to more complex hospitals end up missing the opportunity due to the unavailability of rooms, which in its turn leads to a natural selection of patients.
These examples allow us to see the complexity in health management in the pediatric department.
In 1994, our pediatric cardiac surgery group, working at the Hospital Israelita Albert Einstein (HIAE), was invited by the Assistance Pediatric Directory to perform, in a philanthropic way, surgical corrections in children presenting cardiac defects, being followed up at the institution.
A similar experience with fewer patients was performed through the project Multi Assistance Association (AMA) at the Hospital Samaritano (HS).
Due to the success of this experience and sympathetic to the technical difficulties of colleagues in the same specialty belonging to the "Instituto para la Salud del Niño (ISN)" of Lima, Peru and also the social and economical difficulties of the country (Peru), we decided to accept this new challenge by initiating Humanitarian Missions to the ISN where professionals from the institution would perform operations for the surgical correction of complex cardiac defects. In this mission some theoretical and practical courses have been scheduled aiming a multidisciplinary training.
The recent meeting of pediatric cardiac surgeons in the World Summit on Pediatric and Congenital Heart Surgery held in Montreal (Canada) in June 2008, made possible some Cardiac Surgery Groups and Multidisciplinary Groups of wealthy countries to plan and perform humanitarian missions in third world countries.
More and more often a Health Institution is becoming an integrated system, consisting of a number of organizations, in search of a more harmonious joint action: Community / Physician / Hospital; more adequate to the current reality and without frontiers.
In the period between July 1994 and December 2008, 204 patients presenting congenital heart diseases were submitted to corrective or palliative surgery of cardiac defects.
All the patients were evaluated by the pediatric cardiologist that requested the complementary examinations and performed all the pre-operative procedures, postoperative follow-up and intensive care of the patients.
In the 3 institutions that participated in the study, the intensive care structure was held in Pediatric ICU and the intensive physicians were pediatricians. All the patients with surgical recommendation were presented in the specialty meeting.
The patients were rated according severity of their cardiac defects and surgical risk, according to international rules: Risk Adjustment Congenital Heart Surgery (RACHS) (Table 11)

Statistical analysis
The relationships between hospital mortality and these risk factors were examined with Q2 (Siegel-2006). A p value of less than 0.05 or 5% was considered to be significant.

Discussion
Even though the incidence of congenital heart disease not being significantly high, the restrict number of specialized centers, as well as the number of professionals and the high costs of procedures, make the surgical referrals increase proportionally with the population growth, though the amount of surgeries does not increase in the same proportion and many patients miss the opportunity to have surgical correction or simply end up dying.
Although the number of pediatric cardiac surgeries performed in public Institutions is noticeably increasing, unfortunately it is still not sufficient in order to put an end to the prolonged lines awaiting an opportunity for treatment.
In our field, many private hospitals well structured, sympathizing with this situation and motivated by the exemption of income tax, perform an important Welfare Work in the pediatric area. Undoubtedly, multiplying these services throughout the country is necessary, and by doing so, it would definitely have an immediate impact on the quality of assistance, the training of professionals and the surgical results.
Our group initiated its Philanthropic Activities in 1994 at the HIAE, supported by the Directory in effect, aiming the implementation of a Pediatric Cardiac Surgery Program, followed by the philanthropic assistance of children with cardiac malformation referred by the Pediatric Assistance Service originating from the poorest areas of the city and state of São Paulo. The immediate results of this philanthropic program for the treatment of more complex cardiac malformations allowed the access of patients from other states in the country.
Alongside with the theoretical and practical training of professionals in the area enabled the establishment of work regulations and protocols of conduct in the specialty.
Pediatric Cardiac Surgery Services are frequently in deficit or poorly developed in many countries around the world and currently there are several active foundations with services of cardiovascular support, specialized in the pediatric area, in business for 15 years, aiming to give humanitarian assistance, in the 4 continents, to a very restricted number of excluded patients.
The experience acquired with philanthropic assistance activities enabled the attainment of some experience which constituted an essential tool in order to embrace programs of humanitarian assistance. Between June, 2004 andDecember, 2007; 7 missions to Lima-Peru were realized, supported by the Ministério de La Salud of that country and we operated an average of 8 patients per mission.
Despite the well structured institutions assisting patients of the specialty, the technical resources for diagnosis and therapy, as well as the human resources ones were somewhat different for the philanthropic patients operated in the country, taking advantage of a more advanced technology, when compared to the one present in the humanitarian missions. As expected, the majority of the operated patients belong to the philanthropic group (75%) (HIAE= 65.1% and HS= 9.9 %), when compared to the humanitarian mission group (25%) (ISN= 25.0%).
When the operated patients were classified considering the surgical risk, according RACHS, we observed that the majority is in the Risk Group II and III (69.6%) and that none of the patients in Risk Group VII was operated.

Conclusions
Patients operated belonged to the 5 categories of Rachs risk, being that the Risk Group III was the most numerous (36.2%) -The results obtained at the HIAE and at the ISN, are justified by the number of patients, complexity of cardiac defects operated and structural difficulties in the implementation stage of the Pediatric Cardiac Surgery Service. The mortality in the Risk Group V, was higher than estimated by the Rachs study. On the other hand, in this study, neither did we consider the social-economical conditions of the patient nor the clinical ones, such as: malnutrition, pulmonary infection, type of clinical treatment that largely interfere in the final results in our experience.