Posterior Papillary Muscle Rupture Complicating an ST-segment Myocardial Infarction

An 80-year-old man with a past history of hypertension presented to an Emergency Department with chest pain for 2 h. His blood pressure was 80/60 mm Hg, heart rate was 124 beats/min, respiratory rate was 24 breaths/min, and oxygen saturation was 80% on a non-rebreather face mask. There was no jugular venous distension. The cardiac examination was pertinent for tachycardia and normal S1 and S2 heart sounds, without an audible murmur. Lungs had rales bilaterally. The remainder of the examination was unremarkable. An electrocardiogram showed sinus tachycardia with 3-mm ST-segment elevations in leads II, III, and aVF. He was transferred to our institution for primary percutaneous intervention. A transthoracic echocardiogram showed inferolateral wall akinesis, a normal left ventricular ejection fraction of 60%, and a ruptured posteromedial papillary muscle (Figure 1A ) with wide-open mitral regurgitation (Figure 1B). Coronary angiography showed occlusion of the distal left circumflex artery, with mild changes in the remaining coronary arteries. The patient was intubated for respiratory distress, an intra-aortic balloon pump was inserted, and he was referred to the operating room for emergency mitral valve surgery. An intra-operative transesophageal echocardiogram confirmed a ruptured posteromedial papillary muscle (Figure 2). He underwent a mitral valve replacement with a 27-mm St. Jude Medical Epic tissue valve (St. Jude Medical Inc., St. Paul, MN), and was discharged in good health on hospital day 9.