Abstract 2052: Reduced Spectral Component of Low Frequency Heart Rate Variability is an Independent Predictor of Morbidity and Mortality in Heart Failure. Data from Val-HeFT
Background: In heart failure (HF), reduced heart rate variability (HRV) in the low frequency spectral band (LF, 0.04–0.15 Hz) is a marker of adrenergic activation and may be an important prognostic marker. The aim of the present study was to test the independent predictive role of HRV on the combined endpoint of mortality and morbidity (mainly hospitalization for HF, M&M) in a large multicenter trial, Val-HeFT, which also evaluated neurohormonal markers.
Methods: Baseline 24h Holter recordings were performed in 415 HF patients in sinus rhythm randomised in the ValHeFT Holter sub-study. Three measures of HRV were considered: mean heart rate, 24h SDNN and LF power, categorised according to quartiles and tested against the reference category, defined as the lowest risk. Univariate and multivariate Cox regression analyses were performed for each of the three parameters.
Results: In univariate analysis, clinical predictors statistically significant were: LVEF (p=0.001), NYHA III-IV class (p=0.001), BNP>97 pg/mL (p<0.001), β-blocker therapy (p=0.003). Among HRV measures only reduced LF power was significantly related to the combined endpoint (M&M), in both univariate and multivariate analyses (Table⇓).
Conclusions: Reduced variability in the LF band has been shown to have an important predictive role. This may be reflective of its role as a marker of adrenergic activation. This emerging index (together with BNP measurement) may contribute to improve non-invasive prognostic stratification of HF patients.