Largest Lyapunov index of EHRV for analyzing status of cardiovascular system

摘要

This paper mainly studied exercise heart rate variability (EHRV) which was extracted by exercise electrogram (EECG) recorded during step exercise test.Largest Lyapunov index (LLI) was calculated from EHRV to analysis two groups of hypertensives and controls.The whole exercise duration was divided to three stages,namely pre exercise stage (PES),exercise stage (ES) and after exercise stage (AES).And LLI was calculated in three durations respectively.All the indexes were analyzed with statistics,LLI of AES was found to be significantly different between hypertensives and controls,and as an effective parameter,it could be used to reflect the status of cardiovascular system.