Severe "silent" mitral regurgitation after myocardial infarction: a clinical conundrum

Diagnostic Pitfalls in Papillary Muscle Rupture-Associated Acute Mitral Regurgitation after Acute Myocardial Infarction

Papillary muscle rupture (PMR) is a rare and fatal complication of acute myocardial infarction (AMI). We report a case of acute mitral regurgitation (MR) due to PMR with pulmonary edema and cardiogenic shock following AMI with small myocardial necrosis. An 88-year-old woman was brought to our emergency department in acute respiratory distress, shock, and coma. She had no systolic murmur, and transthoracic echocardiography was inconclusive. Coronary angiography showed obstruction of the posterior descending branch of the right coronary artery. Although the infarction was small, the hemodynamics did not improve. Transesophageal echocardiography established papillary muscle rupture with severe mitral regurgitation 5 days after admission. Thereafter, the patient and her family did not consent to heart surgery, and she eventually died of progressive heart failure. Physicians should be aware of papillary muscle rupture with acute mitral regurgitation following AMI in patients with unstable hemodynamics, no systolic murmur, and no abnormalities revealed on transthoracic echocardiography.

Papillary Muscle Rupture Complicating Acute Myocardial Infarction: A Tale of Teamwork

A 52-year-old man presented with acute onset of chest pain and was found to have an inferolateral ST-segment elevation myocardial infarction and acute mitral regurgitation due to papillary muscle rupture. This case describes a rare, potentially fatal mechanical complication of acute myocardial infarction. (Level of Difficulty: Beginner.)

[A case of emergency surgery for acute mitral regurgitation due to complete papillary muscle rupture as complication of acute inferior myocardial infarction]

We experienced a case with acute mitral regurgitation caused by complete posterior papillary muscle rupture as complication of acute inferior myocardial infarction, who underwent successfully emergency operation of mital valve replacement and coronary revascularization in acute stage. A 64-year-old woman developed sudden cardiogenic shock shortly after the onset of acute inferior myocardial infarction. The diagnosis of acute inferior myocardial infarction was based on the electrocardiographic findings. Under IABP support, preoperative coronary angiography visualized total occlusion of segment 3 of the right coronary artery, and preoperative left ventriculography showed akinesis of inferior wall and severe mitral regurgitation. At 6 hours after onset of papillary muscle rupture, emergency operation was performed. At operation, posterior papillary muscle was found to be totally ruptured. Coronary artery revascularization and mitral valve replacement were performed. Postoperative course was uneventful, with 4 days of IABP and 5 days of ventilatory support. She was discharged on the twentieth postoperative day in NYHA class I. Reports of successful emergency operation for total papillary muscle rupture following acute myocardial infarction are rare. Early diagnosis and surgical treatment are mandatory to save this group of patients.

Pitfalls in the diagnosis and management of papillary muscle rupture: a study of four cases and review of the literature

Four cases of papillary muscle rupture occurring in the setting of acute myocardial infarction are presented, which illustrate the following points: the diagnosis may not be apparent at presentation, a mitral regurgitant murmur may be absent, transesophageal echocardiography may establish the diagnosis when transthoracic echocardiography does not, and appropriate surgical correction can lead to excellent functional recovery.