Long range correlations in the heart rate variability following the injury of cardiac arrest

Cardiovascular and neurological recovery following cardiac arrest (CA) largely influence the morbidity and mortality of the patients. Monitoring the cardiovascular system has been an important clinical issue in intensive care unit (ICU). On the other hand, the rhythms of the heart rate variability following CA are still not fully understood, and there are limited number of literatures reporting the cardiovascular function recovery following CA. In this paper, we studied the scaling properties of heart rate variability (HRV) after CA by centered-moving-average-based detrended fluctuation analysis (DFA). Our results showed that the scaling factor of the baseline HRV is close to that of Brownian motion, and after a CA event it shifts to a 1/f noise-like rhythm. DFA could be a promising tool in evaluating the cardiovascular long term recovery following CA injury.