Outcomes of left atrioventricular valve operation following atrioventricular septal defect repair

Background: A left atrioventricular valve (LAVV) operation following repair of an atrioventricular septal defect (AVSD) can be challenging. We sought to describe characteristics and outcomes of patients requiring LAVV operation.

Methods: This was a retrospective review of AVSDs requiring LAVV operation between 2000 and 2020. Patients who experienced adverse events (AEs), defined as the need for a LAVV reoperation (repair or replacement) or death, were compared to patients without AEs. Freedom from AEs was determined using the Kaplan-Meier method. Reoperation and death were characterized in terms of cumulative incidence function, estimated using competing risk models.

Results: Of 843 patients with an AVSD repair, 59 (7.3%) required an LAVV operation and 7 (9%) needed valve replacement. A simple repair (cleft closure and/or annuloplasty) was performed in 26 patients (48.1%) and complex repair using multiple techniques was performed in 28 patients (51.8%). Eleven patients (20%) required further LAVV reoperation, including replacement of mechanical valve in 3, new valve replacement in 6 (2 Melody, 4 mechanical) and re-repair in 2. The cumulative incidence of freedom from AE was 84.1% (95% confidence interval [CI], 75.0%-94.2%) at 1 year, 78.3% (95% CI, 68.2%-90.0%) at 5 years, 73.4% (95% CI, 62.2%-86.7%) at 10 years, and 69.7% (95% CI, 57.5%-84.7%) at 15 years. Cox univariable regression identified lighter weight (P = .027) and early need for LAVV operation (P = .02) as associated with AEs and cleft closure (P = .003) as protective against AEs. The estimated cumulative incidence of reoperation was higher in complex repairs (17.3% [95% CI, 7.8%-38.7%] vs 0.5% [NA] at 1 year (P = .02, Gray's test)). A comparison of eras-2000-2009 and 2010-2020-showed no difference in AEs (P = .96, Grays test).

Conclusions: Adverse outcomes remain common following LAVV operation. Smaller infants and infants requiring earlier operation and complex type repairs are at greatest risk. Future studies should focus on which high-risk LAVVs are more suited to early LAVV replacement.