Differences between sexes in STEMI treatment and outcomes with contemporary primary PCI

Background

Historically, differences in timely reperfusion and outcomes have been described in females who suffer ST-segment elevation myocardial infarction (STEMI). However, there have been improvements in the treatment of STEMI patients with contemporary Percutaneous Coronary Intervention (PCI) strategies.

Methods

Comparisons between sexes were performed on STEMI patients treated with primary PCI over a 4-year period (January 1, 2017–December 31, 2020) from the Queensland Cardiac Outcomes Registry. Primary outcomes were 30-day and 1-year cardiovascular mortality. Secondary outcomes were STEMI performance measures. The total and direct effects of gender on mortality outcomes were estimated using logistic and multinomial logistic regression models.

Results

Overall, 2747 (76% male) were included. Females were on average older (65.9 vs. 61.9 years; p < 0.001), had longer total ischemic time (69 min vs. 52 min; p < 0.001) and less achievement of STEMI performance targets (<90 min) (50% vs. 58%; p < 0.001). There was no evidence for a total (odds ratio [OR] 1.3 (95% confidence interval [CI]: 0.8–2.2; p = 0.35) or direct (adjusted OR 1.2 (95% CI: 0.7–2.1; p = 0.58) effect of female sex on 30-day mortality. One-year mortality was higher in females (6.9% vs. 4.4%; p = 0.014) with total effect estimates consistent with increased risk of cardiovascular mortality (Incidence rate ratio [IRR]: 1.5; 95% CI: 1.0–2.3; p = 0.059) and noncardiovascular mortality (IRR: 2.1; 95% CI: 0.9–4.7; p = 0.077) in females. However, direct (adjusted) effect estimates of cardiovascular mortality (IRR: 1.0; 95% CI: 0.6–1.6; p = 0.94) indicated sex differences were explained by confounders and mediators.

Conclusion

Small sex differences in STEMI performance measures still exist; however, with contemporary primary PCI strategies, sex is not associated with cardiovascular mortality at 30 days or 1 year.