Progressive reduction of heart rate variability with eventual sudden death in two patients.

Open Access
Publisher Website
Google Scholar
Abstract
In two patients with old myocardial infarction and congestive heart failure there was a progressive reduction of heart rate variability and eventual sudden death. The two patients had had three 24 h electrocardiogram recordings within two years of death. The power of two spectral bands was calculated-0.04-0.15 Hz, low frequency power, and 0.15-0.40 Hz, high frequency power. The mean low and high frequency powers over the 24 h recording progressively decreased whereas the frequency of ventricular arrhythmias showed no consistent changes in either patient. The circadian variation in hourly low and high frequency powers in the last 24 h electrocardiogram recordings was much reduced. These results suggest that sequential measurements of heart rate variability may be useful in predicting sudden death.