Acute mitral regurgitation in suspected acute coronary syndrome: what is the cause?

Patients presenting with acute chest pain and suspected acute coronary syndrome (ACS) who have nonobstructive coronary disease on angiography, but new regional wall motion abnormalities are often diagnosed with takotsubo cardiomyopathy (TTC). The cause of TTC is often physical or emotional stress, and this clinical syndrome occurs more often in women than men. When hemodynamically significant mitral regurgitation (MR) accompanies TTC, the mechanism must be carefully elucidated, as systolic anterior motion (SAM) of the mitral valve can cause significant MR and left ventricular outflow tract (LVOT) obstruction. These patients can be conservatively managed, with SAM-associated MR and LVOT obstruction resolving with medical therapy as TTC-associated left ventricular (LV) dysfunction resolves, as opposed to true ACS where further intervention for MR is often necessary. This case report describes 2 cases of TTC presenting with severe MR, who were initially thought to have ACS-associated MR caused by ischemia, but on further echocardiographic interrogation were found to have SAM-associated MR which resolved along with resolution of LV wall motion abnormalities on medical therapy by follow-up echocardiography.