Hypertrophic Cardiomyopathy (HCM) - Expanded Panel

Hypertrophic cardiomyopathy (HCM) is a disease that causes thickening (hypertrophy) of the heart muscle. The heart muscle cells enlarge more than they should, and scarring (fibrosis) often develops between the cells.

Hypertrophic cardiomyopathy is one of the most common human monogenic disorders with prevalence estimates of 1:500. It is also the most common cause for sudden cardiac death among young adults.

HCM is a genetically heterogeneous cardiac muscle disorder with a diverse natural history. Pathogenic variants in one of the genes encoding a component of the sarcomere proteins (i.e., sarcomeric pathogenic variant) are the predominant cause of nonsyndromic hypertrophic cardiomyopathy. Sarcomeres are the basic contractile unit of muscle fiber, and they are composed of two main protein filaments (thin actin and thick myosin filaments). MYBPC3 and MYH7 genes are the most commonly involved genes, and both account for around 70% of the cases of nonsyndromic HCM. Identifying a sarcomeric pathogenic variant has prognostic value; individuals with a sarcomeric pathogenic variant were shown to have earlier onset and higher incidence of adverse outcomes compared to those without a sarcomeric pathogenic variant.

All 37 mitochondrial genes are included in this panel.