A 55-year-old man underwent mitral valve repair 3 months ago for symptomatic severe mitral regurgitation. He felt well until last week when he developed a recurrence of dyspnea on exertion.

On physical exam, his blood pressure is 120/60 mm Hg, pulse is 70 beats per minute and regular, neck veins are flat, and carotid pulses are normal. Lungs are clear to auscultation bilaterally. Cardiac exam reveals a well-healed midline scar, a normal S1 and S2, and no S3 gallop. There is a 2/6 holosystolic murmur at the apex that radiates to the axilla. Extremities are warm with no peripheral edema.

Echocardiography is performed to evaluate left ventricular (LV) systolic function (Figs. 37-1, 37-2, 37-3 and 37-4 and Videos 37-1 to 37-3).