Dyspnea as an Anginal Equivalent: Multimodality Diagnosis of Dynamic, Severe Ischemic Mitral Regurgitation

Dynamic ischemic mitral regurgitation (IMR), provoked by ischemia or exercise, may escape detection at rest and is associated with adverse outcomes.

A 65-year-old man with ischemic cardiomyopathy (left ventricular ejection fraction, 20%) and recurrent left circumflex in-stent restenosis refractory to multiple interventions presented with progressive dyspnea and chest pain. Resting filling pressures were mildly abnormal, though symptoms remained out of proportion to findings. During balloon angioplasty of the left circumflex, transient ischemia provoked large V waves on the pulmonary catheter wedge pressure tracing; simultaneous echocardiography confirmed severe MR that resolved on deflation of the intracoronary balloon. Stress echocardiography corroborated exercise-induced severe MR. Despite revascularization and medical therapy optimization, symptoms persisted, and mitral transcatheter edge-to-edge repair (M-TEER) was performed with successful resolution of symptoms.

Dynamic IMR may be underdiagnosed when diagnostic studies are performed at rest. This case demonstrates concordant invasive and noninvasive provocative strategies for diagnosis, with M-TEER for refractory symptoms.

Dynamic IMR requires a high index of suspicion and provocative multimodality testing. M-TEER may benefit patients with severe IMR refractory to revascularization and optimized medical therapy.