Types of Hypertrophic Cardiomyopathy

Case Examples of Each Variant

Hypertrophic cardiomyopathy (HCM) is a complex cardiovascular condition characterized by an abnormal thickening of the heart muscle in the absence of other causative diseases. This common genetic disorder affects about 1 in 500 individuals worldwide according to recent data. The three distinct types of HCM are asymmetric septal hypertrophy, concentric hypertrophy, and apical hypertrophy.

This article features several case examples and provides a comprehensive discussion of each type of HCM.

Causes of Hypertrophic Cardiomyopathy

HCM is primarily a genetic disorder, with the vast majority of cases resulting from mutations in genes encoding sarcomeric proteins. These proteins are essential for the contractile function of cardiac muscle cells. The genetic basis of HCM involves autosomal dominant inheritance, meaning that a single mutated gene inherited from either parent can lead to the condition. The most commonly implicated genes (about 40%) include MYH7 (beta-myosin heavy chain) and MYBPC3 (cardiac myosin-binding protein C). Mutations in these genes disrupt the normal structure and function of the cardiac sarcomere, leading to abnormal hypertrophy of the heart muscle.