Long-Term Outcomes After Coronary Stent Implantation in Patients Presenting With Versus Without Acute Myocardial Infarction (an Observation from Coronary Revascularization Demonstrating Outcome Study-Kyoto Registry Cohort-2)

It has not been adequately addressed yet how long the excess cardiovascular event risk persists after acute myocardial infarction (AMI) compared with stable coronary artery disease. Of 10,470 consecutive patients who underwent percutaneous coronary intervention either with sirolimus-eluting stent (SES) only or with bare-metal stent (BMS) only in the Coronary Revascularization Demonstrating Outcome Study-Kyoto Registry Cohort-2, 3,710 (SES: n = 820 and BMS: n = 2,890) and 6,760 patients (SES: n = 4,258 and BMS: n = 2,502) presented with AMI (AMI group) and without AMI (non-AMI group), respectively. During the median 5-year follow-up, the excess adjusted risk of the AMI group relative to the non-AMI group for the primary outcome measure (cardiac death or myocardial infarction) was significant (hazard ratio [HR] 1.53, 95% confidence interval [CI] 1.30 to 1.80, p <0.001). However, the excess event risk was limited to the early period within 3 months. Late adjusted risk beyond 3 months was similar between the AMI and non-AMI groups (HR 1.16, 95% CI 0.95 to 1.41, p = 0.15). The higher risk of the AMI group relative to the non-AMI group for stent thrombosis (ST) was significant within 3 months (HR 3.38, 95% CI 2.04 to 5.60, p <0.001), whereas the risk for ST was not different between the 2 groups beyond 3 months (HR 1.11, 95% CI 0.65 to 1.90, p = 0.70). There were no interactions between the types of stents implanted and the risk of the AMI group relative to the non-AMI groups for all the outcome measures including ST. In conclusion, patients with AMI compared with those without AMI were associated with similar late cardiovascular event risk beyond 3 months after percutaneous coronary intervention despite their higher early risk within 3 months.