PROGNOSTIC RELEVANCE OF HEART-RATE-VARIAB ILITY IN PATIENTS WITH DILATED CARDIOMYOPATHY

Sudden cardiac death is frequent in patients with dilated cardiomyopat hy. To assess the risk of an arrhythmic event is still difficult. Here the analysis of the heart rate variability offers new possibilities. Method: 25 patients(18 male, 7 female, age 53 +/- 9 yrs) with dilated cardiomyopathy were included in the study. Analysis of heart rate vari ability assessed by time- and frequency-domain measures was determined from Holter recordings. The mean follow-up was 18 +/- 5 months. Resul ts: 6 patients died (5 of sudden cardiac death, 1 of heart failure), 1 patient with an implanted defibrillator received an adequate shock. P arameters influenced by low- and midfrequent oscillations of the heart rate were significantly lower in patients who died suddenly or had ad equate shocks. The best predictive parameter was the s.d.RR: all patie nts with an s.d.RR < 50 ms had lethal arrhythmias whereas the s.d.RR o f the surviving patients was greater than or equal to 50 ms. No signif icant difference was found for highfrequency parameters, which are mai nly influenced by parasympathetic activity. Conclusion: The analysis o f heart rate variability is of prognostic relevance in patients with d ilated cardiomyopathy. Especially the s.d.RR is able to identify patie nts with a high risk of a sudden cardiac death.