Abstract 2031: Late Clinical Outcomes of Diabetic Patients Randomized in the Occluded Artery Trial (OAT)
In stable, high risk patients with persistent total occlusion of the infarct-related coronary artery, percutaneous coronary intervention (PCI) of this vessel late after myocardial infarction does not reduce the occurrence of death, reinfarction, or heart failure. We speculated that patients with diabetes known to be at higher risk for cardiovascular events who may particularly benefit from revascularization in certain situations may have better outcomes with PCI vs. medical therapy under these conditions. We identified 454 patients (20.6%) with a history of diabetes from 2201 patients enrolled in the original Occluded Artery Trial (OAT) who had total occlusion of the infarct-related artery 3 to 28 days after myocardial infarction who were randomized to PCI vs. optimal medical therapy alone. The composite primary endpoint of death, myocardial reinfarction, or New York Heart Association (NYHA) class IV heart failure was compared between treatment groups, and with those of non-diabetics undergoing each treatment strategy. The 5-year cumulative primary event rate for diabetic patients was 25.5% vs. 15.4% in the non-diabetic cohort (p<0.001). In multivariable analyses of the OAT outcomes, history of diabetes was an independent predictor (p<0.01) for the primary outcome and for fatal or nonfatal recurrent MI. Within the diabetic cohort, the 5-year cumulative primary event rate was 28.6% in the PCI group vs. 22.9% in the medical therapy group (hazard ratio for death, reinfarction, or heart failure in PCI vs. medical therapy 1.36;99% confidence interval [CI], 0.82 to 2.26;P=0.12). The cumulative primary event rate in non-diabetics was 15.7% in the PCI group vs. 13.2% in the medical therapy group (hazard ratio 1.12;99% CI, 0.79 to 1.61;P=0.40). Within the diabetic patient subgroup of the OAT trial, there was no difference in death, myocardial infarction or heart failure during 5-year follow-up in the PCI treatment arm compared with medical therapy. Despite the higher overall risk conferred by the presence of diabetes, PCI does not improve clinical outcomes in this subpopulation, and should not be performed in otherwise stable patients with an occluded infarct-related artery up to 4 weeks after myocardial infarction.