Genetics of Dilated Cardiomyopathy

Abstract

Dilated cardiomyopathy (DCM) is defined as dilation and/or reduced function of one or both ventricles and remains a common disease worldwide. An estimated 40% of cases of familial DCM have an identifiable genetic cause. Accordingly, there is a fast-growing interest in the field of molecular genetics as it pertains to DCM. Many gene mutations have been identified that contribute to phenotypically significant cardiomyopathy. DCM genes can affect a variety of cardiomyocyte functions, and particular genes whose function affects the cell-cell junction and cytoskeleton are associated with increased risk of arrhythmias and sudden cardiac death. Through advancements in next-generation sequencing and cardiac imaging, identification of genetic DCM has improved over the past couple decades, and precision medicine is now at the forefront of treatment for these patients and their families. In addition to standard treatment of heart failure and prevention of arrhythmias and sudden cardiac death, patients with genetic cardiomyopathy stand to benefit from gene mechanism-specific therapies.

Keywords: cardiac magnetic resonance imaging; dilated cardiomyopathy; echocardiography; epidemiology; genetics.

Figure 1

Phase-sensitive inversion recovery MRI sequences showing examples of nonischemic patterns of LGE in DCM (arrows). (a) Characteristic ring-like subepicardial LGE in patient with DCM and DSP mutation. (b) Anteroseptal midmyocardial LGE in a patient with idiopathic DCM. (c) Patient with Duchenne’s muscular dystrophy demonstrating subepicardial LGE of the anterolateral and inferolateral walls. Abbreviations: DCM, dilated cardiomyopathy; LGE, late gadolinium enhancement; MRI, magnetic resonance imaging.