Background. The aim of this study was to investigate whether heart rate variability may predict the outcome in patients with idiopathic dilated cardiomyopathy. Methods. Time-domain and frequency-domain heart rate variability was analyzed on 24-hour Holter recordings of 56 patients with idiopathic dilated cardiomyopathy (70% males, mean age 49 ± 16 years; left ventricular ejection fraction 28 ± 6%). Results. There were 8 cardiac deaths (14.3%) and 11 arrhythmic events (19.6%, either sudden death or sustained ventricular tachycardia) at a follow-up of 18.5 months (range 3-50 months). Furthermore, 6 patients were included in the list for cardiac transplantation, leading to a prevalence of total cardiac events of 37.5% (21 patients). All time-domain and most frequency-domain heart rate variability parameters did not show any significant relationship with the end points. However, a low frequency to high frequency (LF/HF) ratio <1.2 was associated with cardiac death (relative risk-RR 6.8, p <0.03), arrhythmic events (RR 11.0, p <0.004), and total cardiac events (RR 4.8, p <0.002). On the multivariate Cox analysis, no variable showed an independent association with cardiac death, but an LF/HF ratio <1.2 was the only variable independently predictive of arrhythmic events (RR 8.2, p <0.02), and the most powerful predictor of total cardiac events (RR 3.8, p <0.009). Conclusions. Our data show that, in patients with idiopathic dilated cardiomyopathy, a low LF/HF ratio, as assessed on 24-hour Holter recordings, is a powerful predictor of cardiac events.
|Number of pages||8|
|Journal||Italian Heart Journal|
|Publication status||Published - 2000|
- Heart rate variability
- Idiopathic dilated cardiomyopathy
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine