Autonomic markers and cardiovascular and arrhythmic events in heart failure patients: Still a place in prognostication? Data from the GISSI-HF trial

AimsTo investigate the prognostic value of autonomic variables in patients with symptomatic chronic heart failure (HF) treated according to current recommendations.Methods and resultsWe analysed 24 h time-domain [standard deviation of all normal-to-normal RR intervals (SDNN)], frequency-domain [very low frequency and low frequency power (VFLP and LFP)], and non-linear [detrended fluctuation analysis (DFA)] heart rate variability, deceleration capacity (DC), and heart rate turbulence (HRT) in 388 sinus rhythm HF patients enrolled in the GISSI-HF Holter substudy [82 males, age 65 ±10 years, New York Heart Association (NYHA) functional class III-IV 20, left ventricular ejection fraction (LVEF) 33 ±8]. Cardiovascular (CV) mortality and combined sudden death implantable cardioverter defibrillator (ICD) discharge were assessed as a function of continuous variables in the entire population and in patients with LVEF >30 in univariate and multivariable Cox proportional hazards models. After a median of 47 months, 57 patients died of CV causes and 47 experienced the arrhythmic endpoint. For CV mortality, VLFP, LFP, and turbulence slope (TS) improved predictive discrimination (c-index) and risk classification [integrated discrimination improvement (IDI)] when added to clinical variables [age 30 (20 arrhythmic events), the hazard ratio of an impaired TS (30 at increased arrhythmic risk.Trial registration NCT00336336