Prognostic significance of heart rate turbulence following ventricular premature beats in patients with idiopathic dilated cardiomyopathy.
Heart Rate Turbulence in Dilated Cardiomyopathy.


BACKGROUND
The aim of this study was to investigate the prognostic significance of heart rate turbulence (HRT) characterized by HRT onset and slope after ventricular premature beats in patients with idiopathic dilated cardiomyopathy (IDC).


RESULTS
Blinded HRT analysis was performed in 242 patients with IDC who were enrolled in the Marburg Cardiomyopathy database between 1992 and 2000. During 41 +/- 23 months of follow-up, 54 patients (22%) died or underwent heart transplant. On Cox univariate regression analysis, abnormal HRT onset, HRT slope, HRT onset combined with HRT slope, left ventricular (LV) ejection fraction, LV size, and New York Heart Association (NYHA) functional class III showed a significant association with total mortality or the need for heart transplant. On multivariate analysis, abnormal HRT onset identified patients without transplant-free survival, as did LV size and NYHA class III heart failure. Major arrhythmic events were observed in 42 patients (17%) during follow-up. On univariate analysis, abnormal HRT onset, HRT onset combined with HRT slope, male sex, NYHA class III, LV ejection fraction, and LV size were associated with a higher incidence of major arrhythmic events. On multivariate analysis, only LV ejection fraction remained as a significant arrhythmia risk predictor, with a relative risk of 2.2 per 10% decrease in ejection fraction (95% confidence interval 1.5-3.2).


CONCLUSIONS
In this selected patient population with IDC, HRT onset is a significant predictor of transplant-free survival, as are LV size and NYHA class. For arrhythmia risk stratification, however, only LV ejection fraction remained a significant risk predictor on multivariate analysis.
Grimm
Wolfram
W
Department of Cardiology, Hospital of the Philipps-University of Marburg, Marburg, Germany. Wolfram.Grimm@med.uni-marburg.de
Schmidt
Georg
G
Maisch
Bernhard
B
Sharkova
Julia
J
Müller
Hans-Helge
HH
Christ
Michael
M
D017677:Age Distribution; D002311:Cardiomyopathy, Dilated / Q000175:diagnosis* / Q000453:epidemiology* / Q000401:mortality / Q000601:surgery; D015897:Comorbidity; D018572:Disease-Free Survival; D015716:Electrocardiography, Ambulatory / Q000379:methods*; D005858:Germany / Q000453:epidemiology; D016027:Heart Transplantation / Q000401:mortality* / Q000706:statistics & numerical data; D006801:Humans; D008875:Middle Aged; D011237:Predictive Value of Tests; D015995:Prevalence; D011379:Prognosis; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D016037:Single-Blind Method; D016019:Survival Analysis; D018879:Ventricular Premature Complexes / Q000175:diagnosis* / Q000453:epidemiology* / Q000401:mortality / Q000601:surgery