Midterm outcome of mitral valve repair for congenital mitral regurgitation in infants and children

We analyzed the midterm results of children undergoing mitral valve repair without the use of prosthetic materials focusing on mitral annulus growth. From 1991 to 2004, 17 children (median age: 11 months) underwent mitral valve repair (grade III=9, IV=8). Regurgitation was due to prolapsed leaflet in 8 patients, annular dilatation in 4, and restrictive leaflet motion in 5. Preoperative indexed mitral valve diameter and Z-value were compared with those obtained at follow-up. There were no early or late deaths. All patients had an improved regurgitation grade after surgery. MV repair resulted in reduction in the indexed mitral valve diameter (58.2±22.9 vs. 47.3±18.9 mm/m ², P<0.05) and Z-value (3.3±2.3 vs. 0.79±2.2, P<0.05). One patient underwent re-repair, but no patients required mitral valve replacement during the median follow-up period of 95 months. The latest regurgitation grade was absent or I in 4 patients, II in 10 patients, and III in 3 patients. Mitral valve annulus increased by 23% at 3 years and by 49% at 5 years compared with that at surgery. Mitral valve repair without the use of prosthetic materials is feasible for the majority of patients and carries an appropriate growth pattern of the mitral valve annulus after surgery.