Restrictive cardiomyopathy (RCM) is characterized by impaired filling of the ventricles in the presence of normal wall thickness and systolic function. Although idiopathic RCM is rare compared to other types of cardiomyopathy, the effects are severe. Until recently, many sarcomere genes previously described to be causative mutations in hypertrophic cardiomyopathy and dilated cardiomyopathy have been reported in RCM. Nowadays, it is accepted that primary RCM is also within the spectrum of sarcomere disease. However, the relationship between the identified mutations in sarcomere genes and clinical manifestation are complex, and the possible pathogenic mechanisms are not fully understood. Besides, many RCM‐related sarcomere mutations were reported to cause variable clinical phenotype. Occasionally, “phenotype transition” may also be seen in an individual who was previously diagnosed with RCM.
Part of the book: Cardiomyopathies