Relationship between discharge heart rate and mortality in patients after acute myocardial infarction treated with primary percutaneous coronary intervention

Aims In patients with coronary artery disease, the prognostic value of heart rate has been mainly evaluated in patients with left ventricular dysfunction. Patients with ST-segment elevation acute myocardial infarction (STEMI) are currently treated with primary percutaneous coronary intervention (PCI) and in this contemporary population of patients, the relationship between heart rate and mortality during a follow-up >1 year has not been investigated. Methods and results The population comprised 1453 STEMI patients treated with primary PCI. Resting heart rate was measured before discharge and all patients were followed prospectively. Main outcome measure: the endpoints were defined as all-cause mortality and cardiovascular mortality. The median follow-up duration was 40 months. During this period, 83(6%) patients died of which 52(4%) died from cardiovascular disease. After adjusting for parameters reflecting a greater infarct size and the presence of heart failure, heart rate at discharge remained a strong predictor of mortality. Patients with a heart rate of >= 70 b.p.m. had a two times increased risk of cardiovascular mortality at 1- and 4-year follow-up compared with patients with a heart rate <70 b.p.m.. In addition, every increase of 5 b.p.m. in heart rate at discharge was associated with a 29 and 24% increased risk of cardiovascular mortality at 1- and 4-year follow-up, respectively. Conclusion In STEMI patients treated with primary PCI and optimal medical therapy, heart rate at discharge was an important predictor of mortality up to 4 years follow-up even after adjustment for parameters reflecting a greater infarct size and the presence of heart failure.