Surgical management of recurrent subaortic stenosis: a case report of the modified Konno operation

Subaortic stenosis (SAS) is a rare congenital heart defect (CHD), accounting for 1%-2% of all CHD and the second most common type of left ventricular outflow tract (LVOT) obstruction. SAS ranges from localized obstructive membranes to complex tunnel narrowing and often coexists with other CHD like ventricular septal defect, interrupted aortic arch, and aortic coarctation. Despite generally successful surgeries, SAS recurs in 5%-30% of patients, necessitating reoperation. Recurrence factors include younger age at initial surgery, higher preoperative LVOT gradients, and complex anatomical presentations. This report discusses an 11-year-old girl with recurrent SAS who underwent a modified Konno operation. It emphasizes the need for meticulous surgical technique and vigilant postoperative follow-up to manage SAS and reduce recurrence risk effectively. The case highlights the challenges of this CHD and underscores the importance of personalized, comprehensive care strategies.