Dilated Cardiomyopathy: Does Etiological Heterogeneity Portend Clinical Heterogeneity?

The etiology of dilated cardiomyopathy (DC), a disease of the myocardium characterized by dilatation and impaired contraction of the left ventricle or both ventricles, has been actively investigated for several decades. Unfortunately, the cause of DC is still mostly unknown and the diagnosis mainly based on the exclusion of any specific heart muscle disease, that is any disease associated with known cardiac or systemic disorders. However, it is expected that with the increasing understanding of the etiology and the pathogene-sis of DC, the difference between a true primary cardiomyopathy and specific heart muscle diseases will become indistinguishable in the future [1].