Fatal hemoptysis in acute bacterial endocarditis.

Massive hemoptysis is a rare complication of bacterial endocarditis. When seen, it is most often due to septic pulmonary emboli with infarction or rupture of a mycotic aneurysm of the pulmonary artery; these conditions are usually associated with endocarditis of the tricuspid valve. We report a case of fatal hemorrhage into the lung from a mycotic aneurysm of the subclavian artery, which eroded into the left upper lobe; this condition arose as a sequela of staphylococcal endocarditis involving the mitral valve.