Treatment of Acute Myocardial Infarction With Sirolimus-Eluting Stents Results in Chronic Endothelial Dysfunction in the Infarct-Related Coronary Artery

Background-Sirolimus-eluting stent (SES) implantation aggravated endothelial vasomotor dysfunction in infarct-related coronary arteries. Methods and Results-This study examined the effect of SES implantation on the duration of reperfusion-induced endothelial vasomotor dysfunction in infarct-related coronary arteries and on postinfarct left ventricular dysfunction in acute myocardial infarction (AMI). Patients with a first AMI due to occlusion of the left anterior descending coronary artery and successful reperfusion using SES (n = 15) or bare metal stents (BMS; n = 18) were examined. The vasomotor response of the left anterior descending coronary artery to acetylcholine and left ventriculography were examined 2 weeks and 6 months after AMI. At 6 months after AMI, the impairment of epicardial coronary artery dilation and coronary blood flow increase in response to acetylcholine was recovered from 2 weeks after AMI in BMS-treated patients, whereas the responses of SES-treated patients improved but remained impaired compared with BMS-treated patients (% increase in blood flow, 77 +/- 12% in SES versus 116 +/- 15% in BMS at 10 mu g/min of acetylcholine, P < 0.01). Left ventricular regional wall dysfunction in the left anterior descending coronary artery territory improved from 2 weeks to 6 months after AMI in BMS-treated patients but not in SES-treated patients (% improvement of average SD/chord, 6% in SES versus 19% in BMS, P < 0.05), although left ventricular global ejection fraction was similar between the groups at any time points. Conclusions-SES implantation may delay recovery of reperfusion-induced endothelial vasomotor dysfunction in infarct-related coronary arteries and left ventricular regional dysfunction for at least 6 months after AMI. (Circ Cardiovasc Intervent. 2009;2:384-391.)