Cardiomyopathies: From Anatomy to Molecular Medicine

Abstract

Cardiomyopathies are defined as abnormalities of the ventricular myocardium. Pediatric cardiomyopathies are rare diseases. Increasingly, the importance of genetic mutations in the pathogenesis of isolated or syndromic pediatric cardiomyopathies is becoming apparent. Pediatric cardiomyopathies are genetically heterogeneous with many different causative genes and multiple mutations in each gene. Variants in the same gene can cause different phenotypes, and variants in different genes can cause the same cardiomyopathy phenotype. There are multiple modes of inheritance for cardiomyopathies, including autosomal dominant, autosomal recessive, X-linked, and mitochondrial. Published guidelines have recommended approaches for genetic testing and family screening in patients with isolated, autosomal-dominant cardiomyopathy. The increasing application of genomic analysis to the pediatric cardiomyopathy population is creating a wealth of information that requires expanded registry participation to further understanding of the pathogenic mechanisms underlying pediatric cardiomyopathies and the genetic, environmental, and other, as of yet undiscovered, modifying factors that impact the severity of disease. This compendium summarizes current knowledge of the genetic and molecular origins of the most common phenotypic presentations of pediatric cardiomyopathies and highlights key areas where additional research is required.