EFFECT OF PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY ON CIRCULATING ENDOTHELIN LEVELS

Percutaneous transluminal coronary angioplasty (PTCA) is frequently as sociated with vasoconstriction involving large vessels as well as micr ocirculation, but the potential mechanisms remain poorly defined. In t his study, we tested the hypothesis that endothelial disruption during PTCA is associated with an increase in circulating levels of endothel in, a potent endothelium-derived vasoconstrictor peptide. Circulating levels of endothelin and other potential vasoactive mediators such as atrial natriuretic factor, epinephrine and norepinsphrine were measure d immediately before and after PTCA in 23 patients with coronary arter y disease. Although there was no change in the endothelin levels after angiography alone (43 +/- 5 vs 44 +/- 7 pg/ml, p = 0.5), there was a significant increase after PTCA (32 +/- 8 to 37 +/- 10 pg/ml, p < 0.00 5). The increase in endothelin was associated with a significant incre ase in atrial natriuretic factor (78 +/- 57 to 129 +/- 131 ng/ml, p = 0.01) and a decrease in epinephrine and norepinephrine levels (111 +/- 64 to 59 +/- 36 pg/ml, p = 0.005, and 1,131 +/- 500 to 811 +/- 311 pg /ml, p = 0.003, respectively). Circulating levels of endothelin did no t correlate with the percent coronary stenosis before or after PTCA or the presence or absence of angiographically visible thrombus. These f indings suggest that endothelial injury during PTCA may be associated with increased circulating levels of endothelin and its counter-regula tory hormone, atrial natriuretic factor, and also with a reciprocal de crease in epinephrine and norepinephrine levels. Thus, these humoral c hanges may modulate changes in coronary vascular tone after PTCA.