Risk Factors for Reintervention in Children with Subvalvular Aortic Stenosis: A 20-Year Single-Center Study.

Subvalvular aortic stenosis (SAS) is a frequent cause of left ventricular outflow tract (LVOT) obstruction in children. Surgical resection is the standard treatment, yet recurrence requiring reintervention remains a significant concern. We aim to identify risk factors associated with surgical reintervention. This retrospective study included 76 patients under 18 years who underwent surgical resection for SAS between 2000 and 2020. Preoperative, intraoperative, and postoperative data were analyzed. The mean age at initial surgery was 5.8 years. In addition to subaortic membrane resection, myomectomy was performed in 73.7% of patients. Reintervention was required in 13.1% of cases, with reintervention-free survival at 5 and 10 years of 93.4% and 89.5%, respectively. Significant predictors of reintervention included younger age and shorter stature at surgery. Myomectomy reduced postoperative gradients but was not protective against recurrence and was associated with a higher rate of conductive disorders requiring pacemakers. While surgical resection of SAS is associated with excellent survival, recurrence remains a concern, especially in younger patients and those with tunnel-like lesions. Individualized surgical planning is essential to balance recurrence risk with potential complications.