A Study On Noninvasive Measurement Method Of Cardiac Contractility Variability And Its Clinical Application

Most patients with heart failure mainly have trouble in reduction in cardiac contractility. It is necessary to monitor and estimate cardiac inotropism, chronotropism, and dromotropism in routine. Based on the research on relationship between cardiac contractility and heart sound, this project intended to study the relationship between cardiac contractility variability and heart rate variability, noninvasive method for evaluating cardiac reserve and its clinical application, contributing to development of a method, which can offer the advantages of being noninvasive, convenient, inexpensive, rapid, simple and easy, objective and quantitative, repeatable, high sensitive and specific.Our studies included a study on the relationship between heart rate variability and cardiac contractility variability, a method of ultrashort-term time domain analysis for heart rate variability, a study on a method and its applications for measuring cardiac contractility and heart rate change trend by using the same device, a study on 6-minute walk test incorporating cardiac contractility change trend and heart rate change trend measurements and its clinical applications, a study on the cardiac contractility change trend of narcotics, and a study on quantification for a sign of cor pulmonale. Particularly, through the studies above, we presented a concept and method for ultrashort-term time domain analysis for heart rate variability, incorporated more directed method for measuring cardiac reserve into 6-minute walk test and expanded 6-minute walk test into a 6-minute exercise test.We participated in several population based surveys of cardiac reserve, through statistical analysis, has observed a very significant differences in cardiac contractility change trend between patients with cardiovascular diseases and healthy subjects, narcotics and normal persons, as well as athletes and ordinary population; studied the feasibility of noninvasive method for measuring cardiac reserve use at bedside, in a clinic, and at home; preliminarily practiced the important thought of large sample and multiple centers in evidence-based medicine.