OBJECTIVES: The purpose of the present study was to assess coronary vasomotor response to exercise after sirolimus-eluting stent (SES) implantation. BACKGROUND: Sirolimus-eluting stents have been shown to markedly reduce the incidence of angiographic and clinical restenosis. However, long-term effects of sirolimus on endothelial function are unknown. METHODS: Coronary vasomotion was evaluated with biplane quantitative coronary angiography at rest and during supine bicycle exercise in 25 patients with coronary artery disease. Eleven patients were treated with a bare-metal stent (BMS) (control group) and 14 patients underwent SES implantation (sirolimus group) for de novo coronary artery lesions. Both groups were studied 6 ± 1 month after the intervention. Minimal luminal diameter; stent diameter; and proximal, distal, and reference vessel diameter were determined. RESULTS: The reference vessel showed exercise-induced vasodilation (+13 ± 4%) in both groups. Vasomotion within the stented vessel segments was abolished. In controls, the adjacent segments proximal and distal to the stent showed exercise-induced vasodilation (+15 ± 3% and +17 ± 4%, respectively). In contrast, there was exercise-induced vasoconstriction of the proximal and distal vessel segments adjacent to SESs (-12 ± 4% and -15 ± 6%, respectively; p < 0.001 vs. corresponding segments of controls). Sublingual nitroglycerin was associated with maximal vasodilation of the proximal and distal vessel segments in both groups. CONCLUSIONS: Implantation of a BMS does not affect physiologic response to exercise proximal and distal to the stent. However, SESs are associated with exercise-induced paradoxic coronary vasoconstriction of the adjacent vessel segments, although vasodilatory response to nitroglycerin is maintained. These observations suggest (drug-induced) endothelial dysfunction as the underlying mechanism. © 2005 by the American College of Cardiology Foundation.
Togni, M., Windecker, S., Cocchia, R., Wenaweser, P., Cook, S., Billinger, M., … Hess, O. M. (2005). Sirolimus-eluting stents associated with paradoxic coronary vasoconstriction. Journal of the American College of Cardiology, 46(2), 231–236. https://doi.org/10.1016/j.jacc.2005.01.062