Association between time to percutaneous coronary intervention and hospital mortality in non-STEMI: a prospective...

This study aimed to investigate the association between time to percutaneous coronary intervention (PCI) and hospital mortality in non-ST-elevation myocardial infarction (NSTEMI).

Adult patients with NSTEMI were enrolled from November 2007 to December 2012 at 28 emergency departments (EDs) in Korea, excluding those who met the following criteria: age less than 20 years, PCI not performed or performed after 72 hours, cardiac arrest at ED presentation, and unknown outcome. Exposure variable was defined as early PCI (<6 hours after ED arrival) and late PCI group (≥6 hours). The primary outcome was hospital mortality. The adjusted odds ratios (ORs) with 95% confidence intervals (95% CIs) for late vs early PCI on mortality were calculated in original data set and propensity score-matched data set using multivariable logistic regression models with/without interaction term (PCI group and time from symptom to ED arrival within 12 hours, or S2D).

A total of 4363 patients were analyzed as early (n = 1109) and late (n = 3254) PCI groups. The mortality rates were 2.4%, 5.4%, and 1.5% for the total, early, and late PCI groups, respectively. Adjusted ORs (95% CIs) of late PCI for hospital mortality were 0.36 (0.22-0.61) in the original cohort and 0.29 (0.27-0.48) in the propensity score-matched cohort, respectively. Adjusted ORs (95% CIs) in the propensity score-matched subset were 0.28 (0.17-0.45) in the short S2D group and 0.50 (0.18-1.37) in the long S2D group, respectively.

Percutaneous coronary intervention earlier than 6 hours after ED presentation was associated with higher hospital mortality than PCI 6 hours later in NSTEMI. However, the effect disappeared in the long S2D group.