Repair of complete common atrioventricular canal defects in patients younger than four months of age.

BACKGROUND: The purpose of this study was to evaluate the impact of age at repair and atrioventricular (AV) valve anatomy on preoperative and postoperative AV valve incompetence (AVVR) was done to test the hypothesis that early repair (less than 4 months of life) can be safely accomplished and not only control heart failure but also improve surgical results on AV valve reconstruction.

METHODS AND RESULTS: One hundred patients, median age 6.1 months, underwent repair of the complete common AV canal defect (CAVC) between 1981 and 1996. Surgery was performed in 37 patients (37%) less than 4 months of age (Group 1) and in 63 patients (63%) more than 4 months of age (Group 2). Surgical correction included double patch septal reconstruction in all. Trifoliate reconstruction of the left AV valve was selected in 93 patients (93%). Parametric time-related predicted survival was 92.9% at 14 years in Group 1 (70% confidence limits, 87.6% to 96.1%) and 75.9% at 15.4 years in Group 2 (70% confidence limits, 70.08% to 81.02%) (P=.038). Multivariate analysis in hazard function domain shows early repair as a negative risk factor for death (P=.038). Ordinal logistic regression equation indicates a higher probability of preoperative AVVR with older age at operation (P=.019). Regression analysis demonstrates good correlation between annular size and age at repair (r=.87, P < .01) and between annular size and AVVR (r=0.68, P < .01). Parametric time-related predicted freedom from reoperation was 82.7% at 15.4 years (70% confidence limits, 76.9% to 88.5%). Multivariate analysis in hazard function domain demonstrated Down's syndrome as a negative risk factor for reoperation (P=.05), whereas annular dilation increased the risk of this event (P=.027).

CONCLUSIONS: Early correction of CAVCs is safe and beneficial not only in controlling chronic heart failure, but also in preventing annular dilation secondary to large QP/QS, as a potential mechanism of preoperative AVVR. Annular dilation is an incremental risk factor for reoperation. Early correction according to the double patch technique and trifoliate approach to the left AV valve reconstruction allows respect of valvar and subvalvar apparatus architecture, with a low incidence of postoperative AVVR, excellent survival rate, and low reoperative rate for residual AVVR.