Changing patterns of mitral stenosis in childhood and pregnancy in Sri Lanka.
The findings in rheumatic mitral stenosis appear to have undergone changes, probably in association with improved socioeconomic conditions, in developing countries. The objective of this study was to assess such changes and to adapt strategies of management. The clinical and pathologic features, mortality rate, long-term functional class and restenosis rate in 168 children and 62 pregnant women who underwent closed transventricular mitral valvotomy in the first 14-year period (June 1964 to May 1978) were compared and correlated with those of 140 children and 106 pregnant women in the following 7-year period (June 1978 to May 1985). During the late period, there were attenuated severity of the disease, emergence of a mild pathologic type of valve involvement confined to the commissures (commissural band stenosis), decreased mortality (1.2%) and restenosis rates (p less than 0.001) and increased long-term improvement (p less than 0.001) during childhood. The best results of closed valvotomy were obtained in simple commissural and commissural band stenosis, the latter forming the predominant group in children and pregnant women in the late period (p less than 0.001). Poor results were observed in patients with the subtype of combined stenosis characterized by commissural rigidity, cuspal stenosis and chordal fusion, demonstrating the inapplicability of closed valvotomy. Closed valvotomy is safe in all stages of pregnancy, as evidenced by the zero mortality rate and rate (1.8%) of fetal death, and offers good long-term palliation. However, in pregnant women with pure mitral stenosis characterized by simple commissural or commissural band stenosis, balloon valvuloplasty is an acceptable alternative, especially in light of the risks associated with surgery. The choice of the procedure for the relief of stenosis is determined by the pathologic anatomy of the valve stenosis.