Eclipsed Severe Mitral Regurgitation Without Obstructive Coronary Artery Disease.

BACKGROUND: Ischemic secondary mitral regurgitation (MR) from left ventricular remodeling and geometric mitral valve changes is well recognized. Rarely, severe MR occurs with preserved left ventricular systolic function. CASE SUMMARY: A 70-year-old man presented with chest pain, global ischemic electrocardiography changes, and pulmonary congestion. During an anginal episode, transthoracic echocardiography revealed transient posterior-wall hypokinesis and torrential MR, both resolving as symptoms subsided. Invasive coronary angiography demonstrated moderate coronary artery disease in the left anterior descending artery, with negative resting full-cycle ratio. Intracoronary acetylcholine provocation testing confirmed coronary vasospasm; microvascular dysfunction was excluded. Beta-blocker therapy was ceased, and calcium-channel blocker therapy was up-titrated with good effect, improving the patient's angina and dyspnea. DISCUSSION: Only 6 previous studies have described cases of severe secondary MR from vasospastic angina resulting in leaflet tenting. TAKE-HOME MESSAGES: Eclipsed MR is rare and may be under-recognized. In the current case, treatment of coronary vasospasm resulted in marked symptomatic improvement.