Surgical treatment of congenital mitral valvar insufficiency: ''The Hopital Broussais'' experience

There are many congenital malformations of the mitral valve which produce valvar insufficiency. From a surgical point of view, systems based exclusively on anatomic analysis are not always entirely appropriate for assessment of these lesions. With this in mind, Carpentier proposed a functional approach for analysis based upon the motion of the valvar leaflets. From 1969 to 1994, 135 children under the age of 12 (mean age: 5.8 + 3.15 Y,0.6-12Y) underwent surgery in our department, basing treatment on such analysis. Since motion of the leaflets during the operation is compromised by cardioplegia, and sometimes exposure can be however difficult, preoperative echocardiography was a mandatory part of the diagnostic cascade. Normal motion of the leaflets was present in 41 patients, with deformation of the annulus in 14, a cleft in 21, and partial agenesis in 6. Prolapse of leaflets was present in 42 patients. Leaflet motion was restricted in 28 patients. These were divided in two groups, one with normal papillary muscles and commissural fusion(7) or short cords.(6) The other with abnormal papillary muscles producing a parachute arrangement in 6 and a hammock valve in 9. Associated lesions were present in 47% of the patients. Conservative surgical procedures following the precepts developed by Carpentier were used in 127 patients. Valvar replacement was necessary in 8 patients. Operative mortality was 4%. Mean follow up was 8.4 +/- 5.3 years (1-23Y). Actuarial survival at 5 years was 90 +/- 6% and, at this time, was stable. No thromboembolic events occurred after conservative surgery. The reoperation rate was 5% for those undergoing repair (6 patients). We conclude that the functional classification developed by Carpentier is a reliable and robust approach to these complex lesions. Conservative surgery is feasible in most of the cases presenting with congenital mitral valvar insufficiency. Results are stable and reliable. Surgery should be undertaken before the onset of left ventricular deterioration.