SCN5A Cardiomyopathy: from Ion Channel Dysfunction To Clinical Disease

Area of Science:

• Cardiovascular Genetics
• Molecular Cardiology
• Genetic Basis of Cardiomyopathy

Background:

• SCN5A variants are known causes of cardiac arrhythmia and conduction disease.
• The association between SCN5A variants and dilated cardiomyopathy (DCM) is less understood.
• This review focuses on SCN5A-related cardiomyopathy, bridging structural and electrical heart conditions.

Purpose of the Study:

• To review current knowledge on SCN5A-related cardiomyopathy.
• To explore genotype-phenotype correlations in SCN5A-associated DCM.
• To examine the overlap between SCN5A variants, arrhythmia, and cardiomyopathy, and discuss management strategies.

Main Methods:

• Literature review of recent studies on SCN5A variants and cardiomyopathy.
• Analysis of genotype-phenotype correlations.
• Synthesis of findings on arrhythmia overlap and management implications.

Main Results:

• SCN5A variants, both gain- and loss-of-function, are found in 0.5-0.9% of DCM cases.
• Phenotypes range from isolated DCM to overlapping structural and electrical heart disease, affecting all ages.
• High prevalence of arrhythmias and conduction disease suggests electrical disturbances may mediate DCM, but direct structural effects are also possible due to high variability and intrafamilial heterogeneity.

Conclusions:

• SCN5A-related cardiomyopathy is a rare condition at the intersection of structural and electrical heart disease.
• Genotype-informed management, including arrhythmia control and early genetic screening, is clinically important.
• Further research is needed to define SCN5A-specific risk management strategies for DCM patients.