Aims: To evaluate temporal trends in percutaneous mitral commissurotomy (PMC) in terms of changes in patient characteristics and their impact on immediate results.
Methods and results: From 1986 to 2001, PMC was indicated in 2773 consecutive patients. Patient characteristics and results were compared each year and linear trends were analysed. There were significant trends toward an increase in mean age (p <0.0001) and the proportion of patients in NYHA class I or II before PMC (p <0.0001), and toward a decrease in the proportion of atrial fibrillation (p <0.0002) and favourable valve anatomy (p < 0.0001), but no change in initial valve area ( p < 0.22). Technical failure occurred in 32 patients (1.2%). The failure rate decreased from 6.4% in 1986-1987 to 3.6% in 1988 and was less than 1.5% from then on (p < 0.0001). The frequency of good immediate results (valve area > or =1.5 cm(2) without regurgitation >2/4) did not differ over the years ( p < 0.22), with a mean rate of 89.5% of effective procedures and 88.5% of all procedures.
Conclusion: Over this 15-year period, candidates for PMC became older and had a less favourable anatomy, but underwent PMC at an earlier functional stage. The stability of the results, despite the less favourable characteristics, may be related to the role of experience in improving the technique and patient selection.