Admission heart rate predicts mortality following primary percutaneous coronary intervention for ST-elevation myocardial infarction: an observational study

Background: The prognostic value of admission heart rate (HR) on long-term mortality in ST-elevation myocardial infarction (STEMI) remains uncertain in the modern era of primary percutaneous coronary intervention (PPCI). This study aimed to assess the predictive value of admission HR on long-term mortality following PPCI and the influence of beta-blockers on postdischarge survival.

Methods: Retrospective analysis of prospectively collected data on 2310 PPCI-treated STEMI patients at a regional tertiary center between March 2008 and June 2010.

Results: Patients were classified according to admission HR into either low (≤70 beat per minute [bpm], n = 1015) or high HR group (>70 bpm, n = 1295). At a median follow-up of 559 days, all-cause mortality was 7.0% in the low HR group compared to 12.7% in the high-HR group. In the Cox proportional hazard model, adjusted for several confounders, the hazard ratio (95% confidence interval) for all-cause mortality in the high HR group was 1.59 (1.15-2.20; P = 0.005). Every 10-bpm increase in admission HR was associated with 17% increase in all-cause mortality. Beta-blockers on discharge was associated with a reduction in postdischarge mortality only in the high HR group (adjusted hazard ratio, 0.49 [0.31-0.77; P = 0.002]), but not in the low HR group (adjusted hazard ratio, 0.74 [0.37-1.49; P = 0.33]).

Conclusions: Elevated admission heart rate in PPCI-treated STEMI patients is associated with long-term all-cause mortality. Beta blocker therapy improved postdischarge survival in patients with elevated admission heart rate.