RESUMO
Papillary muscle rupture is an infrequent but often fatal mechanical complication of acute myocardial infarction (AMI). We report the case of an AMI complicated by the development of an abrupt cardiogenic shock due to the rupture of the head of the postero-medial papillary muscle with echocardiographic demonstration of severe mitral regurgitation due to flail posterior mitral valve leaflet. After initial stabilization with medical therapy and diagnostic coronary angiography, the patient was referred for urgent cardiac surgery and successfully underwent mitral valve replacement with implantation of a bioprosthesis. This case confirms the importance of transthoracic echocardiography in diagnosing mechanical acute complications during an AMI and in the decision making of patients with sudden onset of hemodynamic compromise. Transthoracic echocardiography should be immediately carried out in all patients in whom a mechanical complication during an AMI is suspected.