Study On Multivariate Reference Range Of R+S Wave Amplitude Based On Depth Function And Clinical Evaluation

ObjectiveThe purpose of this experiment is to explore the significance of a method which is used as a reference method to electrocardiogram (ECG) consultation. This method can be demonstrated by establishing a multivariate reference range of R+S wave amplitude whose data was measured from a large number of normal ECG based on Mahalanobis Depth Function (MHD), then choose left ventricular mass index (LVMI) detected by ultrasonic cardiogram (UCG) as the diagnostic criteria of left ventricular hypertrophy (LVH), compare the sensibility、specificity of the multivariate reference range of R+S wave amplitude of normal ECG with the common standard:Sokolow-lyon standard and Cornell standard.MethodsTake healthy young people who had a physical examination in the affiliated hospital of Binzhou Medical University as the objects, choose1021(male,244; female,777) normal ECG and use MHD to establish a multivariate reference range for R+S wave amplitude of normal ECG according to gender. Then take meddle-aged patients in the hospital as the objects, use LVMI detected by UCG as the diagnostic criteria of LVH, choose75patients (male,41; female,34) who were diagnosed as LVH as the case group and89people (male,40; female,49) without of LVH as the control group, use MHD to calculate the statistics depth values of R+S wave amplitude in their ECG. Prove the applicability between the multivariate reference range of R+S wave amplitude of healthy young people and that of meddle-aged people by calculating95%confidence interval (CI), study the sensibility、specificity and accuracy about LVH, and compare these indicators with them of Sokolow-lyon standard and Cornell standard.Results1. A multivariate reference range of R+S wave amplitude based on MHD has been established as follows:R+S wave amplitude of normal young male:a95%CI of multivariate reference range’ Depth≥0.0217725; normal young female:a95%CI of multivariate reference range’ Depth≥0.0162415. 2. Mahalanobis depth function of R+S wave amplitude of the case group and the control group has always been calculated and the details can be seen in table4and table5. The multivariate reference range of R+S wave amplitude of healthy young people has been proven that it’s always applied to meddle-aged people by calculating the95%CI.3. In the diagnosis of LVH, the sensibility of MHD, Sokolow-lyon and Cornell standard are69.33%,54.67%,58.67%; the specificity are94.38%,96.63%,97.78%, and the accuracy are82.93%,77.44%,79.88%.ConclusionsIt can be concluded from this experiment that establishing a multivariate reference range of R+S wave amplitude of normal people based on MHD is a new exploration to the method which can judge whether R+S wave amplitude of one ECG is higher or lower. Under the conditions of the existing samples, use a=0.05level, it can’t be believed that the sensibility and specificity of MHD are different from common standard as Sokolow-lyon standard and Cornell standard in the diagnosis of LVH.