Adult Obstructive Cor Triatriatum with Severe Mitral Regurgitation: A Case Report

Adult cor triatriatum sinister associated with severe mitral regurgitation is extremely rare. As these obstructive cor triatriatum feature hemodynamics that mimic mitral stenosis, a pressure load is theoretically generated only on the left atrial proximal chamber, and therefore the left ventricle is less likely to suffer volume loading. Here, we report a surgical case with such rare hemodynamics. A 22-year-old man with obstructive cor triatriatum and severe mitral regurgitation received an anomalous membrane excision and mitral annuloplasty. An abnormal membrane with an orifice 7 mm in size was completely resected while a grossly dilated mitral annulus was repaired via annuloplasty ring. Mitral regurgitation was controlled well, and the postoperative course was uneventful. Even with obstructive cor triatriatum, severe mitral annular dilatation and subsequent left ventricular dilatation may occur, causing the progressive heart failure encountered in this case.