Invasive versus conservative strategy in acute coronary syndromes: The paradox in women's outcomes

BACKGROUND: We explored benefits and risks of an early invasive compared with a conservative strategy in women versus men after non-ST elevation acute coronary syndromes (NSTE-ACS) using the ISACS-TC database. METHODS: From October 2010 to May 2014, 4145 patients were diagnosed as having a NSTE-ACS. We excluded 258 patients managed with coronary bypass surgery. Of the remaining 3887 patients, 1737 underwent PCI (26% women). The primary endpoint was the composite of 30-day mortality and severe left ventricular dysfunction defined as an ejection fraction <40% at discharge. RESULTS: Women were older and more likely to exhibit more risk factors and Killip Class ≥2 at admission as compared with men. In patients who underwent PCI, peri-procedural myocardial injury was not different among sexes (3.1% vs. 3.2%). Women undergoing PCI experienced higher rates of the composite endpoint (8.9% vs. 4.9%, p=0.002) and 30-day mortality (4.4% vs. 2.0%, p=0.008) compared with men, whereas those who managed with only routine medical therapy (RMT) did not show any sex difference in outcomes. In multivariable analysis, female sex was associated with favorable outcomes (adjusted HR for the composite endpoint: 0.72, 95% CI: 0.58-0.91) in patients managed with RMT, but not in those undergoing PCI (adjusted HR: 0.96, 95% CI: 0.61-1.52). CONCLUSIONS: We observed a more favorable outcome in women than men when patients were managed with RMT. Women and men undergoing PCI have similar outcomes. These data suggest caution in extrapolating the results from men to women in an overall population of patients in the context of different therapeutic strategies.