Hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy is a multigenetic cardiac disease with autosomal dominant pattern of inheritance and incomplete penetrance, with the exclusion of those cases caused by mutations in the mitochondrial genome. The disease is usually caused by mutations in several sarcomeric contractile protein genes. Mutations have been found in four genes that encode components of the thick filament: beta myosin heavy chain (5), essential myosin light chains (6), regulatory myosin light chains (6), and cardiac myosin binding protein -C (7), (8); in five genes that encode thin filament proteins: cardiac actin (9), cardiac troponin T (10), cardiac troponin C (11), cardiac troponin I (12), and alpha-tropomyosin (10); and in the sarcomeric cytoskeletal protein titin (13). In addition to mutations in contractile sarcomeric proteins, mutations in other genes encoding for non-sarcomeric proteins also have been identified in patients with-non pure form of hypertrophic cardiomyopathy. As a complex cardiac disease, hypertrophic cardiomyopathy has unique pathophysiological characteristics and a various morphological, functional, and clinical features.