Confirm a clinical diagnosis of Cardiomyopathy and identify presymptomatic family member, guiding prophylactic measures.
This analysis does not rule out germline mosaicism, the presence of large chromosomal aberrations (including deletions, insertions, and rearrangements), mutations in regions or genes not included in this test, and possible inter/intragenic interactions between sequence variants. False-positive or false-negative results may occur for reasons that include genetic variants, blood transfusions, bone marrow transplantation, mislabeled specimens, or erroneous representation of family relationships.
Cardiomyopathies are generally characterized by weakening and impaired contractile function of the myocardium that leads to ventricular hypertrophy or dilation. Myocardial dysfunction associated with cardiomyopathy can either be of mechanical or electrical etiology. The four major types of cardiomyopathy include dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C), and restrictive cardiomyopathy (RCM). Rarer types include left ventricular noncompaction (LVNC) and the amyloid-associated cardiomyopathies, such as transthyretin (TTR) amyloidosis and apolipoprotein A-1 amyloidosis (AApoA-1).
Many cardiomyopathies are now recognized as familial conditions that may be transmitted in an autosomal dominant, autosomal recessive, X-linked, or mitochondrial manner. Genetic testing for the presence of germline mutations in the genes known to be associated with cardiomyopathy may:
• Confirm a diagnosis of familial cardiomyopathy.
• Identify which subtype of a particular cardiomyopathy.
• Identify family members of an index patient who harbor the familial mutation and may wish to undergo cardiac screening at regular intervals.
• Facilitate appropriate genetic counseling for family members.
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