Long-term endothelial dysfunction after coronary artery stenting

OBJECTIVES We assessed the endothelial-dependent vasomotor function in nonr estenotic coronary arteries more than six months following stent implantati on, balloon angioplasty (BA), and directional atherectomy (DCA). BACKGROUND Catheter-based coronary interventions are associated with extens ive arterial injury. Endothelial function has been shown to remain chronica lly abnormal after vascular injury. The long-term effects of different perc utaneous coronary interventions on endothelial function are not known. METHODS Thirty-nine patients treated at least six months earlier with a cor onary intervention for isolated proximal left anterior descending (LAD) ste nosis, with no evidence of restenosis, were studied. Twelve patients had be en stented, 15 had been treated with BA, and 12 had undergone DCA. Changes in diameter of the intervened LAD, and the unintervened circumflex coronary artery (Cx), in response to intracoronary acetylcholine infusions mere ass essed by quantitative angiography. RESULTS The groups had similar angiographic characteristics and risk factor s for endothelial dysfunction. The LAD constricted significantly more (p = 0.02) in previously stented patients (-21.8 +/- 4.3%), as compared to patie nts previously treated with BA (-9.5 +/- 2.8%) or with DCA(-9.1 +/- 3.6%). In contrast, acetylcholine infusion resulted in mild constriction in the Cx , which was similar in the three groups (p = 0.47). By multiple regression analysis, previous implant of a stent was the only significant predictor of LAD constriction (p = 0.008). CONCLUSIONS More severe endothelial dysfunction was observed long term afte r stenting as compared to BA or DCA. These findings may have implications w ith respect to the progression of atherosclerosis in coronary, arteries sub jected to percutaneous interventions, (C) 1999 by the American College of C ardiology.