Effects of intracoronary nitroglycerin on lumen diameter during early follow-up angiography after coronary excimer laser atherectomy

Abstract

The incidence of coronary vasospasm during and following excimer laser atherectomy is considerable. The aim of this study was to investigate vasoconstriction of the target vessel during early follow-up angiography. In 50 patients an angiogram was performed 24 hours after intervention. Nineteen patients were treated with stand-alone laser atherectomy (group I), another 19 with laser and additional balloon angioplasty (group II) and 12 with balloon angioplasty alone (group III). Lumen diameter and percent stenosis before and after intracoronary application of 0.1 mg nitroglycerin were determined. The differences were compared between groups I, II and III, and for patients with (N = 14) and without (N = 24) vasospasm during laser atherectomy. There was a significant increase in lumen diameter, of 0.17 +/- 0.28 mm, after nitroglycerin in group I, of 0.18 +/- 0.29 mm in group II (P = 0.02) and of 0.03 +/- 0.21 mm in group III (ns). In patients with vasospasm during laser atherectomy the average increase in lumen diameter was 0.28 +/- 0.24 mm (P less than 0.01), and in patients without vasospasm 0.12 +/- 0.29 mm (P = 0.09). We conclude that one day after coronary excimer laser atherectomy intracoronary nitroglycerin significantly affects lumen diameter at the site of previous stenosis, an effect undetectable after balloon angioplasty. Thus, vasoconstriction after excimer laser ablation seems to be a common phenomenon and is prolonged in patients with vasospasm during the previous intervention.