Molecular bases of arrhythmias in patients with genetic cardiomyopathies: when the cytoskeleton meets the ion channels

Cardiomyopathies represent a significant clinical and social issue due to their high morbidity and mortality. In addition to myocardial dysfunction, the often associated arrhythmias are an additional risk factor for morbidity and mortality in heart failure individuals. Arrhythmias are frequently correlated to cardiac pump failure, but they may develop in asymptomatic heart failure subjects with preserved ejection fraction and stable hemodynamic performance. Up to date, arrhythmias have been explained by the occurrence of cardiac valve diseases or myocardial morphological alterations. However, recent evidence suggests a tight structural and functional link, at the molecular level, between ion channels and cytoskeletal proteins involved in the structural alterations that lead to heart failure. Furthermore, mutations in these structural proteins may cause ion channel dysfunction resulting in a higher risk of arrhythmias. These new elements of investigation may allow a better understanding of the arrhythmogenic phenomenon in heart failure patients and facilitate alternative research approaches and innovative clinical applications.