Carvedilol can restore the multifractal properties of heart beat dynamics in patients with advanced congestive heart failure

Introduction: Human heart beats in an extremely inhomogeneous and non-stationary manner. Recent study has demonstrated that it belongs to a class of signals called multifractal. Loss of multifractality was also uncovered in patients with congestive heart failure. We investigated whether carvedilol could restore the multifractal properties in a group of patients with advanced congestive heart failure. Methods and results: A Holter ECG recording was obtained before and 1 and 3 months after titrated addition of carvedilol therapy in 10 patients with advanced congestive heart failure. Multifractal spectrum, detrended fluctuation analysis (DFA) as well as the traditional time- and frequency-domain heart rate variability (HRV) parameters were compared before and after carvedilol therapy together with those in age and sex-matched normal control. The results showed that the multifractal spectrum τ(q) vs. q of N-N interval time series returned toward normal during carvedilol treatment. All the tranditional HRV parameters and the short-term DFA improved significantly after 3 months of carvedilol therapy. Conclusion: We concluded that the deteriorated multifractal properties could be reversed by carvedilol treatment in patients with advanced congestive heart failure.