RESUMO
Local and systemic effects of intracoronary (two bolus injections of 25 micrograms at 3-min intervals) ergonovine were determined in 60 patients with angiographic non-spastic normal coronary arteries and were compared with the most usual intravenous ergonovine dose to induce coronary artery spasm (incremental doses of 50, 100 and 200 micrograms at 3-min intervals). The mean diameter of the vessels was reduced by 15% after selective injections (baseline 2.38 +/- 0.7; after intracoronary ergonovine 2.02 +/- 0.6 mm; p less than 0.001) and no significant changes were induced in the heart rate (before 80 +/- 15; after 79 +/- 15 beats/min) and systolic aortic pressure (before 147 +/- 27; after 149 +/- 28 mmHg). Following intravenous administration, the mean coronary diameter decreased by 20% (1.90 +/- 0.6 mm; p less than 0.01 vs intracoronary dose) and the heart rate diminished slightly (76 +/- 12 beats/min; p less than 0.01). Nevertheless, the systolic aortic pressure did increase by 16% (171 +/- 28 mmHg; p less than 0.001). No major complications were observed and the appearance of side effects was minimal. Thus, the intracoronary delivery route, at the applied dosage, induces lesser vasoconstriction than usual intravenous administration, and systemic effects, such as hypertension, are avoided.