Pulmonary hemodynamics at rest and effort, 6 and 12 months after mitral valve replacement: a slow regression of effort pulmonary hypertension.

An analysis of pulmonary hemodynamics in 22 patients with postrheumatic mitral valve disease using a floating Swan-Ganz type catheter at rest and effort in supine cycloergometer test was done before, 6 and 12 months after mitral valve replacement. Pulmonary hemodynamics data were recorded and calculated at rest and during effort. The most significant changes in almost all analyzed parameters occurred between preoperative and 6 month examination values. However further modest changes mainly during effort were observed between the 6-month and 1-year follow-ups. The mean workload during the bicycle ergometer test rose significantly from 22 +/- 26 W before to 48 +/- 20 W at 6 months and 57 +/- 22 W at 12 months after mitral valve replacement (P < 0.005). We noted a significant improvement in functional class 6 months after mitral valve replacement and a further slight improvement 12 months after. There was a small statistically insignificant decrease in systolic pulmonary pressure between 6 and 12 month measurements. Systolic pulmonary pressure at rest dropped slightly from 39.0 +/- 9.4 to 34.6 +/- 9.4 mmHg. During the bicycle test after 3 min (25 W) the decrease of systolic pulmonary pressure between the 6- and 12-month measurements was statistically significant. Systolic pulmonary artery pressure dropped from 61 +/- 12.4 to 50 +/- 12.3 mmHg. At the same time the drop in pulmonary wedge pressure was smaller and statistically not significant. Pulmonary wedge pressure at rest 6 months after mitral valve replacement was 14.3 +/- 6 mmHg, and after 12 months was 12.7 +/- 4.5; at 25 W, 24.6 +/- 6 vs. 22.1 +/- 5.5, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)