Background: Limited data are available for sex-based differences in Japanese patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI).
Methods and results: The study patients comprised 1,197 women and 3,182 men who underwent primary PCI for AMI in 2005-2007. Compared with the men, the women were significantly older, and had significantly longer onset-to-balloon time and lower rate of follow-up coronary angiography. In-hospital mortality was higher among women than men (8.7% vs. 4.9%, P<0.001). Although the cumulative incidence of all-cause death at 3 years was also higher for women (17.7% vs. 10.7%, P<0.001), the adjusted risk for all-cause death was comparable [hazard ratio (HR, women vs. men)=0.94, 95% confidence interval (CI): 0.71-1.24, P=0.66]. The incidence (12.1% vs. 12.4%, P=0.77) and the adjusted risk (HR=0.99, 95% CI 0.78-1.24, P=0.92) for any clinically-driven coronary revascularization were both comparable. However, regarding any non-clinically-driven coronary revascularization, the incidence (19.6% vs. 27.8%, P<0.001) and the adjusted risk (HR=0.79, 95% CI 0.65-0.95, P=0.012) were both lower in women relative to men.
Conclusions: In current Japanese clinical practice for AMI, onset-to-balloon time was significantly longer in women than in men. Female sex was associated with lower follow-up coronary angiography rate and lower incidence of any non-clinically-driven coronary revascularization, whereas the incidence of any clinically-driven coronary revascularization was comparable between the sexes.