Relationship of female sex to outcomes after myocardial infarction with persistent total occlusion of the infarct artery: analysis of the Occluded Artery Trial (OAT).

backgroundLong-term follow-up (up to 9 years) from the OAT allows for the examination of sex differences in outcomes and the effect of percutaneous coronary intervention (PCI) in a relatively homogeneous cohort of myocardial infarction (MI) survivors.

methodsThe OAT randomized 484 (22%) women and 1717 men to PCI of the occluded infarct-related artery vs medical therapy alone >24 hours post-MI. There was no benefit of PCI on the composite of death, MI, and class IV heart failure. We analyzed outcomes by sex and investigated for sex-based trial selection bias using a concurrent registry.

resultsWomen were older and more likely to have left anterior descending infarct-related artery, diabetes and hypertension, history of heart failure, and rales at randomization but were less likely to smoke. The proportion and characteristics of women enrolled in the trial and the registry were similar, including left ventricular ejection fraction and extent of disease. Women had higher rates of the primary composite (hazard ratio [HR] 1.48, P = .0002), death (HR 1.50, P = .001), and heart failure (HR 2.53, P < .0001) but not reinfarction (HR 1.12, P = .57). Female sex was not independently associated with the primary end point or death on multivariate analysis. There was a trend toward independent association of female sex with heart failure (HR 1.66, P = .02).

conclusionWomen in OAT had a higher primary end point event rate than did men, mainly driven by heart failure. Female sex was not independently associated with death or MI in this well-defined cohort with comparable extent of coronary artery disease, similar medical therapy, and equivalent left ventricular ejection fraction by sex.