Intracoronary serotonin release after high-pressure coronary stenting

It is known that platelet-derived serotonin at the site of coronary angiopl asty induces an increase in coronary tone and plays a role in vasoconstrict ion after balloon angioplasty. The goal of the present investigation was to compare local release of serotonin with changes in coronary tone after cor onary stenting and coronary angioplasty. Twenty patients with significant s tenosis (greater than or equal to 50% diameter narrowing) of the left anter ior descending coronary artery were referred to traditional coronary angiop lasty (10 patients; group 1) or high-pressure coronary stenting (10 patient s; group 2). An additional 16 patients with similar angiographic characteri stics were referred to the coronary angioplasty group (8 patients; group la ) or stenting group (8 patients; group 2a) after pretreatment with ketanser in. Serotonin plasma levels in coronary sinus and coronary cross-sectional area distal to the site of dilatation were measured before and after both r evascularization procedures. In groups 1 and la, plasma serotonin levels in coronary sinus increased from basal values of 3.2 +/- 0.8 and 3.2 +/- 0.5 ng/ml to 29.5 +/- 13 and 25.6 +/- 9 ng/ml after ballooning (p <0.001 vs bas eline). In groups 2 and 2a, plasma serotonin levels in coronary sinus incre ased from basal values of 3.5 +/- 0.3 and 3.5 +/- 0.7 ng/ml to 114.6 +/- 34 and 113 +/- 29 ng/ml after scenting (p <0.001 vs baseline and vs postangio plasty values in groups 1 and 1a). Coronary cross-sectional area distal to the site of dilatation significantly decreased after angioplasty in group 1 (from 4.33 +/- 0.4 to 3.32 +/- 0.3 mm(2) p <0.001), and after stenting in group 2 (from 4.27 +/- 1.3 to 2.86 +/- 0.2 mm(2); p <0.001 vs baseline, and p <0.02 vs values after coronary angioplasty in group 1). Pretreatment wit h ketanserin significantly reduced distal coronary vasoconstriction after a ngioplasty and stenting. It is concluded that the higher local serotonin re lease after coronary stenting may explain the more marked coronary constric tion observed after prosthesis deployment with respect to traditional coron ary angioplasty. Ketanserin is able to significantly attenuate the increase in distal coronary tone induced by both revascularization procedures. (C) 1999 by Excerpta Medico, Inc.