Correlation between symbolic dynamics analysis indexes and neurohormonal and functional parameters in heart failure...

Heart failure (HF) is a cardiac disease associated with prominent alterations in the autonomic control of the cardiovascular system and high neurohormonal activation levels. Useful assessment tools may be heart rate variability (HRV) analysis and/or the study of norepinephrine (NPE) level. Nevertheless, traditional techniques of HRV analysis have proved not sufficient and the second is an invasive measurement. In this work the correlation between a parameter (kurtosis-K) computed by an emerging nonlinear technique, the symbolic dynamics analysis, and neurohormonal and functional parameters has been investigated. Results obtained show an interesting relationship between K and both ejection fraction and NPE. In particular, higher K values are associated to increasing NPE levels This finding could be useful for highlighting changes in HF patients otherwise detectable only with invasive examinations.