Surgical results of mitral valve repair for congenital mitral valve stenosis in paediatric patients.

OBJECTIVES

Mitral valve (MV) repairs have been performed in paediatric patients with congenital MV stenosis. However, congenital MV stenosis lesions are a heterogeneous group of lesions, and their repair remains challenging.

METHODS

From March 1999 to September 2014, MV repair was performed in 22 patients with congenital MV stenosis. The median age was 10.3 months (ranging from 22 days to 9.1 years), and the mean body weight was 7.9 ± 4.0 kg at the time of the operation. Multiple-level left-side heart obstructions were present in 9 (45%) patients.

RESULTS

The main aetiology of the mitral stenosis was a supravalvular mitral ring in 8 patients, valvular stenosis in 4 patients, a parachute deformity of the papillary muscles in 4 patients and other abnormal papillary muscles in 6 patients. The mean MV pressure gradient improved from 10.4 ± 3.9 mmHg to 3.4 ± 1.7 mmHg after MV repair (n = 18, P < 0.0001). The mean follow-up duration was 6.7 ± 5.4 years. One patient died postoperatively due to septic shock. Four patients required a second operation (2 patients for mitral stenosis, 1 patient for left ventricular outflow tract obstruction and mitral stenosis and 1 patient for mitral regurgitation). Among them, 2 patients died: 1 patient died due to cardiopulmonary bypass weaning failure and another patient died due to multiple cerebral infarcts. At the last follow-up, the mean MV pressure gradient was 4.5 ± 3.1 mmHg for all patients who did not have reoperation, and moderate or greater mitral insufficiency was detected in 3 patients. At 10 years, the survival rate was 85.9 ± 7.6%, and the freedom from reoperation rate was 77.5 ± 10.1%. In the log-rank test, MV repair in the neonate was associated with mortality (P = 0.010), and presentation of mitral insufficiency was associated with reoperation (P = 0.003).

CONCLUSIONS

MV repair in paediatric patients with congenital mitral stenosis showed acceptable results. The follow-up echocardiogram also revealed satisfactory results. Close follow-up is necessary to detect the development of postoperative mitral stenosis or regurgitation.