Considerations on the Mitral Valve During Total Correction of Complete Atrioventricular Canal in Infancy Using the Two-Patch Technique

Abstract

Between May 1985 and September 1987 eight patients ranging in age from 2 to 9 months (mean 5.9 months) underwent intracardiac correction of complete atrioventricular (AV) canal (CAVC). The CAVC was of type A in one case, type B in two (25%), type C in three (37.5%), and two cases represented a mixed form (type A-B or B-C) (Rastelli’s classification).

All patients suffered from severe pulmonary hypertension with preoperative calculated left-to-right shunt varying between 53% and 76%. Five patients (62.5%) presented with associated cardiovascular lesions including secundum atrial septal defect (two), left superior vena cava (one), and patent ductus arteriosus (four).

In all patients intracardiac correction of CAVC consisted of implantation of two separate patches closing the ventricular and atrial septal defects. Our technique allows for preservation of the basic architecture of the common AV valve. Special attention was paid to obtaining an unobstructed mitral orifice by partitioning the common AV valve far enough to its tricuspid portion.

One patient (12.5%) died during the early postoperative course, there was no late death. The seven surviving patients are symptom free, with postoperative follow-up now ranging from 4 to 20 months.

This series, although small, demonstrates that this lesion can be corrected, even in very small infants, with an excellent chance of good clinical and hemodynamic results.