Application Of Lorenz Plot In Heart Rate Variability Analysis In Patients With Coronary Heart Disease

Objective:To investigate the correlation between the frequency domain and time domain index in the linear analysis method and the nonlinear analysis method-Lorenz scatter plot index of heart rate variability(HRV)in patients with coronary heart disease(CHD),and to find more accurate HRV.Methods:100 patients with coronary heart disease in our hospital during the period of 2017.01-2018.01 were collected as coronary heart disease group,and 100 healthy subjects were used as control group.The 24-hour dynamic electrocardiogram of each group was collected and the corresponding Lorenz scatter plot was drawn.The occurrence of arrhythmia in each group was statistically analyzed.Time domain index(SDNN,r MSSD and PNN)and frequency domain indicators(HF,LF)in the linear analysis method and the length L,width W,area A,scatter plot pattern of Lorenz scatter plot were monitored and compared.The time-domain and frequency-domain indicators of the 24-hour ambulatory electrocardiogram Lorenz plot in CHD group were compared with control group.Results:1.Compared with the control group,the length L,width W,area A of the Lorenz scatter plot of the coronary heart disease group and the linear analysis method showed significant decrease of SDNN and LF(p<0.001).2.The sinus pattern of Lorenz scatter plot in coronary heart disease group was mostly comet-shaped,torpedo-like,short-rod,fusiform and irregular,while the control group was dominated by comet-like shape.Compared with the irregular shape,there was a statistical difference(P<0.05).3.The length L of the Lorenz scatter plots of the two groups is significantly correlated with the time domain indices SDNN,r MSSD and PNN 50 in the linear analysis method.The width W of the scatter plot is significantly correlated with the frequency domain indices HF and LF in the linear analysis method(p< 0.001).4.The incidence of arrhythmia in the coronary heart disease group was significantly higher than that in the normal control group(p< 0.001).5.In patients with myocardial infarction,the sensitivity and accuracy of Lorenz scatter plot anomaly were significantly higher than the abnormal standard SDNN<100ms in the time domain index,which had a higher diagnostic value(P<0.05)..Conclusion: 1.The nonlinear analysis method of heart rate variability Lorenz scatter plot index is significantly correlated with time domain and frequency domain indicators in linear analysis method.The purpose of qualitative and quantitative analysis of HRV change can be achieved by using scatter plot indicators and graphical morphology.2.The time domain frequency index of patients with coronary heart disease is lower than that of normal people.The Lorenz scatter plot has large dispersion and various forms,and the incidence of arrhythmia is significantly higher than that of normal people.3.The Lorenz scatter plot is more intuitive and accurate in responding to the decline in heart rate variability in patients with myocardial infarction than the time domain index.