Fate of significant left atrioventricular valve residual gradient after atrioventricular canal repair

Abstract

Reoperation for left atrioventricular valve (LAVV) dysfunction after complete repair is a well-known situation. Although regurgitation is the main cause, few studies review the fate of postoperative residual stenosis. Clinical and echographic outcomes of patients with significant early postoperative gradient of left atrioventricular valve after atrioventricular septal defect (AVSD) repair. Between January 2000 and December 2019, 887 with an AVSD repaired were reviewed. Forty-one of them presented a LAVV mean gradient of more or equal than 5 mmHg at the first postoperative echo. The follow-up postoperative data were obtained from hospital records and cardiologists correspondences. We studied the postoperative mean gradient of the LAVV at discharge, one and tree months, one and five years after the repair. The median follow-up was 51 months (3–123 months). Among the 41 patients included 15 had a complete AVSD (cAVSD) and 26 had a partial AVSD p(AVSD). The median age and weight at repair were 4.5 (2.4–107.5) months, 4.8 (4–19) kg for the complete AVSD (cAVSD) and 50.8 (4.2–200.4) months, 15 (4.7–38.6) kg for the partial AVSD (pAVSD), respectively. Six (40) cAVSD were diagnosed with Down syndrome and 5 (33.3) had a pulmonary artery banding before the repair. There was no reoperation for LAVV stenosis neither for regurgitation. Patients remained asymptomatic with normal range of pulmonary pressure. One patient was reoperated for left ventricular outflow tract obstruction. The median (range) LAVV gradient measured were the following at first postoperative echo, discharge, one and 3 months, one an, last follow-up: 5 (3–10), 4.5 (2–5), 3.4 (1.5–6) (Table 1, Fig. 1). The difference between the first postoperative echo gradient and the last one was not significant (P = 0.47). Significant LAVV gradient after AVSD is not uncommon. Overall trend is the stability of the gradient with normal pulmonary pressure or even decreasing. Isolated LAVV mean gradient between 5 to 10 mmHg does not seem to be an indication for reclamping. A moderate gradient due to the zone of apposition closure and commissural annuloplasty is acceptable when needed to obtain a competent LAVV.