Clinical standard for valve area after common atrioventricular valve plasty for a single ventricle.

Objectives: To determine a clinical standard for post-repair common atrioventricular valve orifice area based on mid- to long-term valve function in patients with a functional single ventricle.

Methods: The medical records of 19 single-ventricle patients who underwent common atrioventricular valve plasty from July 1988 to January 2013 were retrospectively reviewed. Bivalvation valvuloplasty was performed in 7 patients with relatively hypoplastic leaflets. The relationship between the orifice area of the repaired common atrioventricular valve measured intraoperatively and valve function and ventricular volume in the early postoperative period (median, 9.5 months) and at mid- to long-term follow-up (median, 4 years) were analysed.

Results: Post-repair valve area was significantly positively correlated with valve regurgitation severity in the early postoperative period (P = 0.001, r = 0.69) and at mid- to long-term follow-up (P = 0.02, r = 0.57). Patients who did not undergo bivalvation had favourable valve function at mid- to long-term follow-up and in the early postoperative period when the post-repair valve area was 96-136% of the normal mitral valve area. Bivalvation patients had significantly more valve regurgitation in the early postoperative period than patients without bivalvation, despite equivalent repaired valve area (P = 0.02).

Conclusions: The post-repair orifice area of the common atrioventricular valve is significantly related to postoperative valve function. The clinical standard of post-repair valve orifice area might be 96-136% of the normal mitral valve area in patients undergoing repair without bivalvation. Patients undergoing bivalvation require greater reduction to obtain favourable mid- to long-term valve function.