Pulmonary artery pressure and pulmonary vascular resistance before and after mitral balloon valvotomy in 100 patients with severe mitral valve stenosis.

We studied the pulmonary vascular hemodynamics before and after mitral balloon valvotomy in 100 patients with severe mitral valve stenosis. Before balloon valvotomy 23 patients had a pulmonary artery systolic pressure of < 31 mm Hg (group 1), 54 patients had a pulmonary artery systolic pressure between 31 and 50 mm Hg (group 2), and 23 patients had a pulmonary artery systolic pressure of > 50 mm Hg (group 3). After balloon valvotomy the mean systolic pulmonary artery pressure in group 1 decreased from 28 +/- 3 to 26 +/- 5 mm Hg (p = NS). In group 2 the systolic pulmonary artery pressure after balloon valvotomy decreased from 41 +/- 5 to 33 +/- 7 mm Hg (p < 0.0001) and normalized to < 31mm Hg in 27 patients (50%). The mean left atrial pressure was abnormal (> or = 13 mm Hg) in 6 of 27 patients (22%) who had a systolic pulmonary artery systolic pressure of < 31 mm Hg and in 6 of 27 patients (22%) with a pulmonary artery systolic pressure of > or = 31 mm Hg. The pulmonary vascular resistance was abnormal in 36 of 54 patients (67%) after mitral balloon valvotomy; only 5 of 36 patients (14%) had a raised left atrial pressure (> or = 13 mm Hg). In group 3 the pulmonary vascular resistance was abnormal (> 125 dynes/sec/cm-5) in all 23 patients before and in 19 of 31 patients (91%) after balloon valvotomy.(ABSTRACT TRUNCATED AT 250 WORDS)