Hereditary Cardiomyopathies: Types And Characteristics

Cardiomyopathy is a complex condition within the field of internal medicine, with ongoing updates to its definition and classification. Among the various types, primary hereditary cardiomyopathies are frequently observed in clinical settings. These include hypertrophic cardiomyopathy, dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, and left ventricular non-compaction. Each type has distinct features and clinical implications.

Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is one of the most commonly diagnosed genetic heart diseases. It is characterized by abnormal thickening of the heart muscle, particularly the left ventricle. This thickening can cause the heart chamber to shrink and the walls to stiffen, making it harder for the heart to pump blood efficiently. As the condition progresses, the increased muscle mass can paradoxically reduce the heart's ability to contract effectively, eventually leading to heart failure.

Dilated Cardiomyopathy

Dilated cardiomyopathy (DCM) is another significant form of hereditary heart disease. In this condition, the heart muscle becomes weakened and stretched, causing the chambers—especially the left ventricle—to enlarge. As a result, the heart cannot pump blood as effectively as it should, which can lead to heart failure over time. DCM is a common reason for heart transplantation due to its progressive nature.

Arrhythmogenic Right Ventricular Cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC), also known as arrhythmogenic right ventricular dysplasia, primarily affects the right ventricle. In ARVC, normal heart muscle tissue is replaced by fibrofatty tissue, which disrupts the structure and function of the right ventricle. This change can lead to dangerous heart rhythm disorders, including ventricular arrhythmias, which may cause sudden cardiac death, particularly in young athletes.

Left Ventricular Non-Compaction

Left ventricular non-compaction (LVNC) is a rare congenital cardiomyopathy characterized by prominent trabeculations in the left ventricle. This condition results from the failure of myocardial tissue to properly compact during fetal development, leading to a sponge-like appearance of the left ventricular wall. Patients may experience heart failure, arrhythmias, or systemic embolic events due to blood clots forming in the deep trabecular recesses.