Isolated congenital cleft mitral valve leaflet: a rare cause of refractory cardiogenic shock complicating acute myocardial infarction

We report a unique presentation of isolated congenital cleft mitral valve complicating cardiogenic shock from acute myocardial infarction. Isolated cleft mitral valve is an uncommon diagnosis that can have significant clinical implications, especially if not recognized in patients presenting to the catheterization lab with acute myocardial infarction and cardiogenic shock. A review of this rare diagnosis including the options and timing of therapeutic interventions, which can include MitraClip, is important for publication. The case is of a patient who presented with an anterior acute ST elevation myocardial infarction. Despite early coronary revascularization and conventional support, refractory cardiogenic shock ensued requiring mechanical circulatory support escalation to Veno-arterial extracorporeal membrane oxygenation. Subsequently, left ventriculography revealed a massively dilated left atrium and severe mitral regurgitation raising concerns for a mechanical mitral valve complication. The patient was taken to the operating room for possible mitral valve surgery, but a preoperative transesophageal echocardiogram revealed an isolated posterior cleft mitral valve. Since the patient had stabilized on mechanical circulatory support, emergent surgery was deferred. The patient successfully recovered during index hospitalization with mechanical circulatory support and discharged on guideline directed medical therapy. In conclusion, isolated cleft mitral valve is a rare diagnosis that can often be underrecognized without comprehensive 3-dimensional transesophageal echocardiography evaluation. If diagnosed early with significant regurgitation, surgical treatment results in good outcomes and preservation of LV systolic function. Percutaneous correction of a CMVL with MitraClip has been described and may offer an alternative approach for high risk surgical patients.