The natural history of closed mitral commissurotomy--a 20 year follow-up

To study the natural history of mitral stenosis in a Portuguese population submitted to closed commissurotomy. METHODS-POPULATION: All the patients submitted to closed mitral commissurotomy in Pulido Valente Hospital. The commisurotomies were performed from 1956 to 1978 and included a total of 1,134 patients (220 males). Based on the clinical records, we studied the baseline characteristics of all the patients (n = 1134) at the time of surgery. An average of 20 years after surgery, we sent a questionnaire to all these patients. The patients who filled out the questionnaire (n = 352) represented the total Population in terms of the principal clinical characteristics. Based on these answers, we studied the long-term results of closed commissurotomy.

Closed commissurotomy was performed before the age of 20 in about 10% of the patients and after the age of 49 in only 1.6%. The initial symptoms occurred at 22.0 years and commissurotomy was performed at 30.4 years (averages). The procedure was successful: 99% of patients improved significantly after commissurotomy and two thirds had major or total improvement.

In the natural history of these commissurotomized patients the events were early, with symptoms in their twenties and surgery in their thirties. The events occurred earlier in males than in females. Closed commissurotomy presented, in this study and with these patients, very good results with improvement in 99% of the patients. The positive results the commissurotomies were important and long lasting: there was a low rate of re-intervention (16%) and hospitalization (35%) twenty years after surgery and 53% of the patients are still alive. These good results can be, at least in part, explained by the low age of this population at the time of surgery.