Cardiac Autonomic Control in Relation to Other Prognostic Markers in Idiopathic Dilated Cardiomyopathy
World Journal of Cardiovascular Diseases
Objectives: We set out to study cardiac autonomic tone in patients with idiopathic dilated cardiomyopathy (IDC), and whether it correlates with other established markers of disease progression and patient ultimate outcome. Design: Fifty-one IDC patients in sinus rhythm underwent extensive non-invasive and invasive evaluation during a three-day hospitalization period. The control group consisted of thirty-eight apparently healthy subjects who underwent 24-hour ambulatory ECG recording. Results:
... ecording. Results: Heart rate variability (HRV) and heart rate turbulence (HRT) correlated with many previously established prognostic markers of IDC and congestive heart failure, especially measures of cardiorespiratory performance capacity and circulating neurohumoral factors (p < 0.05 for all). Furthermore, attenuated HRV correlated with worse prognosis during a median follow-up of 6.8 years (range 5.1 -8.1). Additionally, 24-hour time domain, low and high frequency components of frequency domain and non-linear HRV, excluding scaling exponents (α), were lower in IDC patients as compared with controls (p < 0.05 for all); however, HRT was not significantly different. Conclusions: The magnitude of impairment in cardiac autonomic control correlates well with other prognostic markers of IDC, and is associated with unfavorable outcome.