Background: In acute coronary syndrome (ACS) patients there are mostly studies evaluating prognostic value of admission heart rate. We tried to understand the prognostic value of discharge heart rate in a spectrum of ACS patients.
Methods: A total of 473 consecutive ACS patients were included in the study. Forty-three (9.1%) of them were unstable angina pectoris, 268 (56.7%) were non-ST elevation myocardial infarction and 162 (34.2%) of them were ST elevation myocardial infarction patients. Discharge heart rates of the patients were recorded and the patients were followed-up for 1 year. The primary end-point was all-cause mortality.
Results: The mean age of the patients was 64 ± 12. The patients were divided into three subgroups according to discharge heart rates (<78, 78-89, ≥90 beats per minute). Patients with a higher discharge heart rate had higher serum troponin, glucose levels and higher admission heart rates, had lower ejection fraction values and had acute heart failure complication more frequently than the patients with a lower discharge heart rate. A total of 72(16%) patients died during 1 year follow-up. In multivariate logistic regression analysis, an increased discharge heart rate was independently associated with 1-month mortality after ACS, but it was not independently associated with 6-month or 1-year mortality after ACS. Every 1 bpm increase in discharge heart rate resulted in a significant increased risk of 8.2% in 1-month all-cause mortality.
Conclusion: Increased heart rate at discharge is an independent predictor of 1-month mortality in ACS patients. This relationship disappears after 1-month through 1-year follow-up.
Keywords: Heart rate; acute myocardial infarction; mortality; patient discharge.