Notwithstanding, due to the high complexity of cardiomyopathies, it is also suggestive that the cause of the malignant condition reported here may be derived from a polygenic synergistic effect of both ACTC1 and TTN variants, where this double hit is necessary to impair the phenotypic manifestation of an early and severe DCM. The gene discussed is ACTC1; the disease is familial dilated cardiomyopathy.