Surgically created double-orifice left atrioventricular valve: A valve-sparing repair in selected atrioventricular septal defects

Objectives: Some features of the left atrioventricular valve (large mural l eaflet, dystrophic tissue) represent a challenge for repair of atrioventric ular septal defects without postoperative regurgitation. A retrospective st udy was conducted to evaluate the results of surgically creating a double-o rifice left atrioventricular valve in such circumstances. Clinical results were analyzed according to valvular and subvalvular left atrioventricular v alve measurements in pathologic specimens with atrioventricular septal defe cts. Methods: Among 157 patients operated on for atrioventricular septal defect since October 1989, 10 patients underwent primary repair (n = 8) or reopera tion (n = 2) by this procedure. Median age at repair was 3.3 years (0.1-33 years). Anatomic types were complete (n = 3), intermediate (n = 5), and par tial (n = 2). Preoperative moderate to severe left atrioventricular valve r egurgitation was present in 6 patients. After the repair (two-patch techniq ue in complete atrioventricular septal defect, cleft closed in each case), these 10 patients were found to have moderate to severe residual regurgitat ion not amenable to repair by annuloplasty. The top edge of the mural leafl et was anchored to the facing free edge of the cleft. Results: No hospital death or morbidity was observed. Left atrioventricular valve regurgitation was absent or trivial (8 patients) and mild (2 patient s). Color-coded echocardiography did not show significant left atrioventric ular valve stenosis. The mean diastolic pressure gradient across the left a trioventricular valve was 3.2 +/- 1.1 mm Hg (1.4-4.5 mm Hg). At a median fo llow-up of 72 months (6-91 months), there was 1 late death, unrelated to le ft atrioventricular valve malfunction, due to pulmonary vascular obstructiv e disease. Left atrioventricular valve regurgitation did not increase over time, except in 1 patient in whom regurgitation recently progressed from mi ld to moderate. At rest, the mean diastolic pressure gradient across the le ft atrioventricular valve was 3.8 +/- 2.9 mm Hg (1.5-11.2 mm Hg). One child had an early moderate stenosis without pulmonary hypertension. Studies on pathologic specimens (n = 34) indicated that long chordal lengths and large mural leaflet size are essential independent anatomic features to assess i ts feasibility. Conclusions: Surgical creation of a double-orifice left atrioventricular va lve is an effective additional procedure for repair of atypical cases of at rioventricular septal defect. The operation may decrease the need for reope ration or left atrioventricular valve replacement.