Coronary cardiac computed tomography (CCTA) has seen rapid improvements in technology including hardware and postprocessing techniques that have contributed to its rapid growth and enabled it to remain in the forefront on diagnostic imaging. Important technological advances include wider detectors for greater coverage with less gantry rotation times, dual-source computed tomography (CT) with improved temporal resolution, dual-energy CT where simultaneous imaging at different energies to increase the contrast difference between different tissues enhances diagnostic accuracy, and emergence of spectral CT to enhance atherosclerotic imaging through nanoparticle technology. Software advances include iterative reconstruction methodologies to reduce noise and radiation doses, plaque imaging and quantification tools to assess plaque morphology and stenosis severity. Processing advances using computational fluid dynamics now enables the determination of fractional flow reserve (FFR). Another important advancement in CCTA physiologic imaging is CCTA perfusion imaging to detect ischemia and compares favorably with myocardial perfusion imaging and coronary angiographic stenosis. Finally, large registry studies and single-center studies have now been published assessing the incremental value of coronary calcium score, CT plaque severity of disease and have demonstrated that the CCTA carries strong prognostic value over and above traditional risk assessment in predicting adverse outcomes.
Part of the book: Computed Tomography
The incidence of peripheral arterial disease (PAD) is rising due to significant increase in metabolic disease such as diabetes mellitus, increase in aging population, and tobacco use. Superficial femoral artery (SFA) disease is the leading cause of peripheral artery disease and claudication. In the last decades, several technologies/techniques have been developed for the treatment of SFA atherosclerotic disease including balloon angioplasty, balloon expanding stents, self-expanding stents, drug-eluting balloon, and atherectomy. The advances made in technology have significantly improved the quality of the balloons, but they have limitations especially in long and calcified lesions. While the initial studies using stainless steel stents failed to show any significant difference in outcomes, understanding the pathophysiology and improvement in stent technologies has shown significant reduction of restenosis by five- to sevenfold when compared to angioplasty alone. Atherectomy is another modality of plaque modification and treatment, which can be done as a stand-alone treatment or more commonly combined with PTA and/or stenting. Finally, several randomized studies and registries have showed that with improvement in technology, there is significant improvement in long-term outcomes of SFA atherosclerotic disease.
Part of the book: Peripheral Arterial Disease