Nonlinear analysis of heart rate variability and plethysmogram in subjects with normal and abnormal cardiovascular function

We used nonlinear methods of Detrended Fluctuation Analysis (DFA) and Recurrence Quantification Analysis (RQA) to analysis of plethysmograms and their peak intervals in subjects with normal and pathological cardiovascular functions. Our results on HRV using DFA showed that scaling exponent indicated quantitatively differentiations among normal and pathologies. The measures of RQA were found to provide an unambiguous and quantitatively characterization of the plethysmogram time series in different cases. Accordingly, the integrations of these two analyses had the ability to identify and quantify normal and pathological cases, implying a possible clinical application.