Severe Ischemic Mitral Regurgitation Despite Normally Contracting Subpapillary Myocardium

Ischemic mitral regurgitation (MR) is common and increases heart failure and mortality after myocardial infarction.1,2 It is caused by left ventricle (LV) remodeling and subsequent papillary muscle (PM) displacement, with secondary mitral leaflet tethering. It can be seen classically in global LV dilatation and dysfunction or with more local remodeling involving the posterior PM and inferoposterior basal to mid LV wall.3 We report a case in which mitral leaflet tethering and severe MR occurred without either of these typical scenarios.An 82-year-old woman presented to the emergency department for recent-onset progressive exertional dyspnea, orthopnea, and lower extremity edema. She had known hypertension with LV hypertrophy, normal systolic function, mitral annular calcification, and mild mitral regurgitation by echocardiogram 6 months previously. Medical history was notable for hyperlipidemia, transient ischemic attack, and family history of coronary artery disease.Initial evaluation revealed overt heart failure with elevated NT-proBNP (> 9000 pg/mL). Chest X-ray showed bilateral pleural effusions and pulmonary vascular redistribution (Figure 1). Cardiac troponins were negative, but ECG showed new T-wave inversions suggestive of anteroseptal ischemia (Figure 2). Echocardiogram revealed …