Complete versus partial atrioventricular canal: Equal risks of repair in the modern era

Objective: To assess the authors' hypothesis that with modern techniques, the current risks of repair for both complete and partial atrioventricular canal (AVC) are equal. Summary Background Data: Repair of complete AVC in infancy has traditionally carried a substantial mortality. In contrast, partial AVC has been considered low-risk for repair and can be performed later in childhood. Methods: This was a retrospective review of 63 infants and children who underwent complete (n = 40) or partial AVC repair (n = 23) from 1990 to 2001. Among complete AVC patients, the ventriculoseptal defect was repaired via an individualized approach according to each patient's specific anatomy: direct suturing without a patch (n = 5) and/or interposition of a small pericardial patch with a running suture (n = 35). In all 63 patients the left AV valve cleft was closed with interrupted sutures, and all atrial defects were closed with a pericardial patch. Data were analyzed with the Student t test and Fisher exact test. Results: Results are expressed as the mean ± SEM. Age at operation was 6.3 ± 2.0 months for complete AVC and 47.5 ± 6.1 months for partial AVC (P < .001). Bypass time was 65.2 ± 2.3 minutes for complete AVC and 58.3 ± 3.9 minutes for partial AVC (P = .1). Reoperation rate was 7.5% (3/40) for complete AVC and 13.0% (3/23) for partial AVC (P = .6). Early mortality was 2.5% (1/40) for complete AVC and 0% (0/23) for partial AVC (P = .6). Conclusions: Compared to partial AVC, patients presenting for complete AVC repair are significantly younger and manifest more complex anatomy and pathophysiology. However, utilizing modern techniques, including an individualized surgical approach to the ventricular component, repair of complete AVC yields reoperation and early mortality rates similar to those of partial AVC.