Percutaneous transvenous mitral commissurotomy: hemodynamic and initial outcome differences between atrial fibrillation and sinus rhythm in rheumatic mitral stenosis patients.

BACKGROUND: Atrial fibrillation (AF) occurs frequently in severe rheumatic mitral stenosis (MS) and has been reported to be a predictor of poor outcome after percutaneous transvenous mitral commissurotomy (PTMC). Nevertheless, according to observations in our catheterization laboratory, patients with sinus rhythm (SR) seem to have a higher pulmonary artery pressure than AF.
PURPOSE: To determine 1) the hemodynamic differences between MS patients with AF and SR before and after PTMC and 2) the success rate and difference in outcome between both groups.
METHOD: A total of 145 patients who had undergone PTMC with the Inoue balloon technique in King Chulalongkorn Memorial Hospital between 1993 and 1997 were enrolled. The data were presented as mean +/- SD. Student t-test was used to compare the difference in hemodynamic and outcome between the AF and SR groups.
RESULTS: Fifty-six patients (38.6%) were in the AF group. The AF patients were older (42.0 +/- 11.3 vs 32.4 +/- 8.7 yr., p < 0.0001), had a larger left atrium (49.2 +/- 6.1 vs 45.3 +/- 4.9 mm, p < 0.001) and a higher valvular calcification score (1.8 +/- 0.6 vs 1.5 +/- 0.6, p = 0.02) than the SR group. There was no significant difference between baseline heart rate and overall MV score index. The hemodynamic data showed that the SR group had higher systolic (59.9 +/- 26.0 vs 47.4 +/- 16.8 mmHg, p < 0.05), diastolic (28.1 +/- 12.8 vs 22.7 +/- 9.2 mmHg, p < 0.05) and mean (40.1 +/- 17.1 vs 32.7 +/- 11.8 mmHg, p < 0.05) pulmonary artery (PA) pressure than the AF group. After successful PTMC, the SR group exhibited a more favorable change in all PA pressures and the transmitral valvular gradient (10.0 +/- 6.5 vs 6.7 +/- 6.5 mmHg, p < 0.01) than the AF group. Procedural success rates were 98 per cent in the AF and 96 per cent in the SR group (p = ns). Transthoracic colour-flow echocardiographic imaging detected atrial septal defects in 18.2 per cent and 7.5 per cent (p = 0.08) of the AF and SR groups, respectively. There was no systemic embolization, peri-procedural death or emergency surgery in both groups.
CONCLUSION: Patients with MS and AF were older, had a larger LA and lower pre-PTMC PA pressure than the patients who had MS and SR. In addition, patients with SR had a more favourable PA and LA pressure reduction than patients with AF.