THE DYNAMIC CHANGE OF PLASMA ENDOTHELIN-1 DURING THE PERIOPERATIVE PERIOD IN PATIENTS WITH RHEUMATIC VALVULAR DISEASE AND SECONDARY PULMONARY-HYPERTENSION

The arterial plasma endothelin-1 concentration was substantially more elevated in 15 patients with rheumatic valvular disease and secondary pulmonary hypertension than in healthy volunteers (3.66 +/- 2.20 versu s 1.17 +/- 0.38 pg/ml, mean +/- standard deviation; p < 0.01) The preo perative plasma endothelin-1 level was highly correlated with the pulm onary hemodynamics: pulmonary artery systolic pressure (r = 0.94, p < 0.001), pulmonary artery mean pressure (r = 0.86, p < 0.001), pulmonar y capillary wedge pressure (r = 0.82, p < 0.001), and pulmonary vascul ar resistance (r = 0.63, p < 0.02). After valve replacement, the plasm a endothelin-1 concentration declined substantially and the pulmonary hemodynamics improved markedly. Two weeks after the operation, the pla sma endothelin-1 level in patients (1.26 +/- 0.45 pg/ml, mean +/- stan dard deviation) was not statistically different from that in the healt hy volunteers. The plasma endothelin-1 concentration continuously incr eased during the course of cardiopulmonary bypass and peaked after ces sation of bypass. The peak plasma endothelin-1 level (13.49 +/- 4.60 p g/ml, mean +/- standard deviation) positively correlated with the bypa ss time (r = 0.64, p < 0.02) and negatively correlated with the urine volume during bypass (r = -0.69, p < 0.01). We conclude that (1) incre ased plasma endothelin-1 might be implicated in the pathogenesis of se condary pulmonary hypertension caused by rheumatic valvular disease an d (2) markedly elevated plasma endothelin-1 concentrations might be as sociated with the mechanism of cardiac or renal dysfunction after prol onged cardiopulmonary bypass.