Left atrioventricular valve repair after primary atrioventricular canal surgery: Predictors of durability

Objective Acute outcomes after atrioventricular canal defects (AVCD) surgery in the current era are excellent; yet despite surgical advances, ∼15% of patients require future left atrioventricular valve (LAVV) repair. Among patients with AVC who undergo LAVV repair after primary AVC surgery, we sought to characterize the durability of these repairs. Specifically, we aimed to determine predictors for reintervention following an LAVV repair in patients with repaired AVCD, with a focus on postoperative transesophageal echocardiography (TEE). Methods We reviewed all patients undergoing LAVV repair (after a primary AVCD surgery) at Boston Children's Hospital between 2010 and 2020. Competing risk analysis was performed to evaluate cumulative incidence of LAVV reinterventions. Predictors of LAVV reintervention were evaluated using multivariable Cox regression. Results A total of 137 LAVV repairs following primary AVCD surgery were performed in 113 patients. Median age and weight at LAVV repair were 25 months (interquartile range, 12-76 months) and 11.1 kg (interquartile range, 7.8-19.4 kg). Original anatomy was complete AVCD in 87 (63%), transitional AVCD in 27 (20%), and partial AVCD in 23 (17%) cases. Over a median follow-up of 12 months (interquartile range, 1.3 months-4 years), 47 (34%) of the LAVV repairs required LAVV reintervention. Reinterventions included a total of 27 LAVV re-repairs and 20 LAVV replacements. In multivariable analysis, age at LAVV repair younger than 72 months, partial AVCD anatomy, left ventricle dysfunction, mean LAVV stenosis gradient ≥5 mm Hg, and multiple jets of regurgitation on postoperative LAVV repair TEE were associated with LAVV reintervention. Grade of LAVV regurgitation on postoperative TEE was not an independent risk factor, but reintervention rates were high when residual LAVV stenosis gradient was ≥5 mm Hg and residual mild LAVV regurgitation was present on postoperative TEE (47%) and even higher when residual LAVV stenosis gradient was ≥5 mm Hg and LAVV regurgitation was greater than mild (73%). Conclusions Reintervention rates remain high for LAVV repairs that occur after primary AVCD surgery, particularly for patients with LAVV stenosis gradient ≥5 mm Hg and mild or greater LAVV regurgitation on postoperative TEE.