Percutaneous revascularization and long term clinical outcomes of diabetic patients randomized in the Occluded Artery Trial (OAT)

Abstract

Background: Percutaneous coronary intervention (PCI) of a persistently totally occluded infarct-related artery (IRA) in stable high-risk patients >24h after myocardial infarction (MI) does not reduce the occurrence of death, re-infarction, or heart failure. Diabetic patients are at higher risk for cardiovascular events; we examined their outcomes overall with PCI and optimal medical therapy alone (MED).

Methods: The long-term (7-year) outcomes of 454 diabetic patients (20.6%) randomized to PCI or MED in the Occluded Artery Trial (OAT) were assessed for the composite primary endpoint of death, re-MI, or New York Heart Association class IV heart failure. Diabetics and non-diabetics were compared and outcomes assessed by treatment strategy.

Results: The 7-year cumulative primary event rate for diabetic patients was 35.0% vs. 19.4% in the non-diabetic cohort (p<0.001). Multivariable analyses revealed diabetes to be an independent predictor (p<0.01) for the primary outcome, fatal or nonfatal recurrent MI, Class IV Heart Failure (HF), and death. The 7-year cumulative primary event rates were 35.3% in the PCI group vs. 34.5% in the medical therapy group in diabetic patients (p=0.19) and 19.3% in the PCI group vs. 19.5% in the medical therapy group in patients without diabetes (p=0.60).

Conclusions: Despite the higher overall risk conferred by the presence of diabetes, PCI did not improve clinical outcomes in this subpopulation, and is not indicated in otherwise stable patients with a totally occluded infarct-related artery in the sub-acute phase after MI.

Keywords: Diabetes; Occluded artery; Open artery hypothesis; Percutaneous coronary intervention.