[Incidental Detection and Surgical Correction of Isolated Left-sided Partial Anomalous Pulmonary Venous Connection in an Adult Patient Requiring Valve Surgery].

Partial anomalous pulmonary venous connection (PAPVC) is a rare congenital anomaly, and isolated left-sided PAPVC without atrial septal defect is extremely uncommon. We report a 70-year-old man with severe mitral regurgitation, atrial fibrillation, and chronic kidney disease, in whom preoperative imaging incidentally revealed left upper pulmonary vein drainage into the innominate vein via a vertical vein. Hemodynamic evaluation demonstrated a significant left-to-right shunt [pulmonary flow/systemic flow( Qp/Qs) =1.88]. Surgical treatment consisted of direct anastomosis of the vertical vein to the left atrial appendage, combined with mitral and tricuspid annuloplasty under cardiopulmonary bypass. The postoperative course was uneventful with stable hemodynamics. This case highlights the importance of careful preoperative imaging to detect rare anomalies such as PAPVC and the need for appropriate surgical planning when concomitant valvular disease is present.