Cardiovascular disease is a common finding in patients with acromegaly. In such patients, heart failure frequently leads to death. Cardiovascular manifestations of acromegaly include cardiomegaly and very often hypertension, coronary atherosclerosis, and diabetes. Primary valvular disease is less commonly observed. Because it is not clear whether acromegaly-related cardiomyopathy is a specific entity and since there are not many necropsy reports regarding mitral valve prolapse in acromegalic patients, we report the case of severe mitral regurgitation due to rupture of the chordae tendinae in a patient with mitral valve prolapse and acromegaly.