Heart, hypertrophic cardiomyopathy, explanted heart, CV169.jpg There is marked left ventricular hypertrophy, with asymmetric bulging of a very large interventricular septum into the left ventricular chamber. This is hypertrophic cardiomyopathy. About half of these cases are familial, though a variety of different genes may be responsible for this disease. Both children and adults can be affected, and sudden death can occur. Seen here is the explanted heart. Pacemaker wires enter the right ventricle. The atria with venous connections, along with great vessels, remained behind to connect to the transplanted heart (provided by someone who cared enough to make transplantation possible).