High Risk Repeated Cardiac Surgery for Recurrent Subaortic Stenosis With a Favorable Outcome: A Case Report

Abstract Subaortic stenosis is a form of left ventricular outflow tract obstruction, accounting for approximately 14% of cases. It occurs as an acquired lesion after repair of congenital heart disease and rarely following mitral valve repair or replacement. A 40-year-old female presented with dyspnea on minimal exertion, palpitations, and chronic hemolytic anemia. Her medical history included cardiac surgery at the age of 10 for closure of an atrial septal defect and mitral valve repair. Then, at the age of 28, she underwent another cardiac surgery to resect a subaortic stenosis, which recurred within one year. This recurrence led to a redo surgery involving mitral valve replacement with a 25-mm St. Jude prosthesis. Subsequent investigations demonstrated membranous subaortic stenosis with severe aortic valve insufficiency and partial de-insertion of the mitral valve with a small atrial septal defect. Management aimed to eliminate all systemic and structural factors contributing to increased flow in the left ventricular outflow tract, which are known to play an important role in the recurrence of subaortic stenosis. For this purpose, the patient underwent the fourth cardiac surgery involving aortic valve replacement, membrane resection, repair of the leak around the mitral valve, and atrial septal defect closure. She recovered within 2 months after surgery and resumed her job. During a 6-year follow-up period, she remained in good health with no evidence of cardiac dysfunction. Despite the considerable risks associated with repeated surgical interventions for recurrent subaortic stenosis, favorable long-term outcomes may outweigh these risks.