FAUT-IL ENCORE FAIRE DES COMMISSUROTOMIES MITRALES A COEUR FERME? A PROPOS DE 168 INTERVENTIONS DONT 108 A COEUR OUVERT ET 60 A COEUR FERME

Mitral commissurotomy is known to give good results but the best surgical technique (open heart or closed heart) remains uncertain. Results of open heart commissurotomy (OC), 108 patients (Group I) and closed heart commissurotomy (CC), 60 patients (Group II) were compared. The population comprised 81% females and the average age was 39 ± 12 years. Only cases of pure or very predominant mitral stenosis (MS) were included. The preoperative state of the patients in Group I was poorer than that in Group II (repeat commissurotomy 8.3% compared to 1.7%, p < 0.04; associated mitral regurgitation 41% compared to 27%, p < 0.04; cardiothoracic ratio 0.54 ± 0.07 compared to 0.51 ± 0.06, p < 0.01). A more complete surgical cure was posible in Group I. Both commissures were liberated in 99% of OC compared to 25% CC (p < 0.001). MItral valvuloplasty was associated in 87% of OC (63 cases on the papillary muscles, 21 cases on the chordae tendinae and 60 cases on the mitral annulus). Operative mortality was low and did not differ significantly between the two groups (zero in CC; 1.8% in OC). Overall survival rates were excellent (95% 5 year survival, 85% 7 year survival). The reoperation rate at 5 years was 7.4% and at 7 years, 23.9%, and did not differ with the surgical technique used. The functional result was good (patients in Class I or II of the NYHA classification 84% at 5 years; 75% at 7 years; identical for both groups). Significant late valvular 'dysfunction' was rare after OC. The valvular result was considered to be poor (significant residual stenosis or regurgitation on clinical, phono or electrocardiographic criteria, haemodynamic data - 22 cases - or operative appearances - 11 cases -) in 30 patients. The incidence of poor results was higher in patients over 40 years of age (34% compared to 12% at 5 years; p < 0.02) and in those with even moderate associatd mitral regurgitation (44% compared to 16% at 6 years, p < 0.01). The incidence of poor results at 5 years was greater after CC than OC (33.6% compared to 11.8%, p < 0.05). This was related to the greater incidence of residual or recurrent stenosis after closed heart surgery (23.6% compared to 3.5% at 5 years, P < 0.01). The superiority of OC was confirmed by echocardiography (EF slope 43 mm/s compared to 33 mm/s, p < 0.001). Therefore, although there were no significant differences in functional result and survival rate, the incidence of poor valvular results was higher after CC. As patients undergoing OC were at a more advanced stage in their disease we believe that OC should replace CC; the advantages of OC are particularly striking in patients over 40 years of age and in patients with moderate mitral regurgitation. CC may still be indicated in selected cases (pregnancy, socio-economic difficulties of cardio-pulmonary bypass).