Prognostic Significance of Short-Period Heart Rate Variability in Patients with Acute Myocardial Infarction in the Era of Modern Infarction Therapy

摘要

We aimed to prospectively assess the prognostic value of decreased heart rate variability (HRV) in the era of modern infarction therapy with high rates of reperfusion therapy and beta-blocker use. Short-term HRV in the frequency domain was measured in 129 consecutive patients (age < 74 years) 5 to 8 days after an acute myocardial infarction (AMI). HRV-parameters were subdivided according to predefined cut-points. Patients were followed for a mean of 38 months (range 1–47) for arrhythmic events, cardiac and noncardiac death, and recurrent nonfatal myocardial infarction or angina requiring hospitalization. The majority of patients received acute revascularization (60 %), and most were treated with b-blockers (89 %) and aspirin (95 %). Accordingly, the rate of endpoints were relatively low (9 deaths or malignant arrhythmias; 14 nonfatal reinfarctions or angina). Patients with the combined endpoint death, malignant arrhythmia or nonfatal cardiac event had significantly lower mean and median low frequency (LF) and total frequency power. Accordingly, the relative risk of reaching any endpoint of those with low LF-power was 2.3 times (Confidence Interval 1.03; 5.3) higher compared to those with normal HRV. This association persisted in the multivariate model controlling for age, ejection fraction and treatment. In conclusion, these data show that in the era of modern infarction therapy with high rates of acute reperfusion therapy and optimized medical therapy, an easily applicable test for autonomic dysfunction, ie short-term HRV-measurement, remains a significant predictor of the patients’ risk for future adverse events.