Balloon mitral valvotomy by using the Twin-AT catheter: immediate results and complications in 110 patients.

Balloon mitral valvotomy, using a new Twin AT catheter (two balloons attached side by side over one shaft), was performed in 110 consecutive cases. The age of the patients ranged from 19-78 yr (mean 46 +/- 15). From a total of 94 females and 16 males, 23 of the patients (22%) had mitral valve calcification, 47 patients (46%) had atrial fibrillation, and 39 patients (37%) had mitral regurgitation (< +2). Twenty patients (18%) presented with restenosis following surgical commissurotomy. Total catheterization time was 101 +/- 26 min and the duration of the valvotomy procedure was 37 +/- 21 min in these cases. For the entire population, there was a significant reduction in mitral valve gradient (15 +/- 6 to 4.8 +/- 2.6 mmHg, p < .001), an increase in mitral valve area (MVA) (1.1 +/- 0.3 to 2.35 +/- 0.7 cm2, p < .001), and a decrease in mean pulmonary arterial pressure (31 +/- 12 to 26 +/- 11, p < .002) after the balloon mitral valvotomy. Sixteen patients (14%) developed significant left to right shunt, and in 22 patients (20%) mitral regurgitation increased moderately but without resulting in emergency valve replacement. There was one incidence of embolic episode and one pericardial tamponade. Adequate hemodynamic results (MVA > 1.5 cm2 and % increase in MVA > or = 50%) without major complications were obtained in 99 cases. In 9 patients with severely diseased valve (2 previous commissurotomy, one restenosis after balloon valvotomy), or small left ventricular cavity, insufficient results were obtained by the Twin-AT catheter.(ABSTRACT TRUNCATED AT 250 WORDS)