Prognostic significance of endothelial dysfunction in patients undergoing percutaneous coronary intervention in the era of drug-eluting stents

BACKGROUND Endothelial function is a prognostic predictor in patients undergoing percutaneous coronary intervention (PCI). However, in an era with widespread use of drug-eluting stents, the clinical relevance of endothelial dysfunction on restenosis in patients undergoing PCI has not been fully evaluated. METHODS This study included 80 patients with stable angina pectoris. Flow-mediated dilation (FMD) of the brachial artery was examined 1 week after PCI. Patients were retrospectively followed-up for an average of 21 months after PCI. The primary endpoints included cardiac death, nonfatal myocardial infarction, stroke, coronary revascularization, and critical limb ischemia. RESULTS A drug-eluting stent was used in 58 patients and a cardiovascular event was recorded in 34 patients during follow-up. The incidence of all cardiovascular diseases was significantly greater in the low FMD (median FMD <4.2%) than the high FMD (median FMD ≥4.2%) group (60% vs. 25%, p <0.01). Furthermore, the incidence of coronary revascularization was significantly higher in the low than the high FMD group (p = 0.02), while the incidence of in-stent restenosis did not differ between the two groups. Cox regression analysis showed that low FMD was an independent predictor of cardiovascular events (hazard ratio: 2.77, 95% confidence interval: 1.23 to 6.19, p = 0.01). CONCLUSIONS Impaired brachial artery FMD independently predicts long-term cardiovascular events after PCI in the era of drug-eluting stents.