The Fate of the Left Atrioventricular Valve After Atrioventricular Septal Defect Repair: Long-Term Outcomes

Abstract

While repair of complete atrioventricular septal defects (CAVSD) has shown excellent results, the need for left atrioventricular valve (LAVV) intervention after the initial CAVSD repair presents therapeutic challenges and potential morbidity. Data on incidence and outcomes of LAVV intervention after primary CAVSD repair remain limited. Retrospective review of the Pediatric Health Information System (PHIS) from 1/2004 to 12/2023. All patients who underwent CAVSD repair were included. LAVV reintervention was defined as mitral valve repair or replacement after initial CAVSD. International Classification of Diseases 9/10 codes were used to identify diagnoses and procedures. 7745 patients underwent CAVSD repair with 4,430 (57.4%) females, 4430 (57.2%) non-Hispanic White, 4250 (54.9%) with Down syndrome, and a median age of 5.4 [IQR: 3.7-10.2] months at repair. Following CAVSD repair, 503 (6.5%) required LAVV reintervention, with 405 (80.5%) repairs and 98 (19.5%) replacements. Median total follow up was 1.99[IQR: 0.09-9.13] years. Freedom from reintervention was 93.8% at 1 year, 88.3% at 5 years, 83.8% at 10 years, and 79.1% at 15 years. Factors associated with LAVV repair included government insurance (HR 0.72; 95% CI 0.57-0.92, p = 0.008), age (per month at CAVSD repair) (HR 0.98; 95% CI 0.97-0.99, p < 0.001), Down syndrome (HR 0.56; 95% CI 0.45-0.88, p = 0.006), and middle-tertile volume center compared to highest tertile (HR 1.24; 95% CI 1.00-1.55; p = 0.044). For LAVV replacement, Down syndrome (HR 0.47; 95% CI 0.30-0.72, p < 0.001) was the only significant factor. In a large multicenter dataset study, LAVV reintervention after CAVSD repair is not uncommon, with an incidence of 7%, emphasizing its long-term management challenges. Our study demonstrated that older age at CAVSD repair and a diagnosis of Down Syndrome were associated with a decreased risk for LAVV reintervention. These findings can help counsel patients/families and help guide surveillance protocols and long-term management in this population.

Keywords: Atrioventricular septal defect; Atrioventricular valve; Congenital heart surgery; Long-term; Outcomes.