This case report presents a woman aged 51 years with coinheritance of pathogenic/likely pathogenic variants of the β-myosin heavy chain (MYH7 p.Glu924Lys) and plakophilin 2 (PKP2 p.Leu442Argfs∗5), each implicated in HCM and ARVC, respectively. The gene discussed is MYH7; the disease is arrhythmogenic right ventricular cardiomyopathy.