The QRS Waveform Of Pacemaker Electrocardiogram Study In Patients With Right Ventricular Septal Pacing

Objective:To compare the QRS waveforms of pacemaker electrocardiogram of the right ventricular septal(RVS) pacing with the traditional right ventricular apical(RVA) pacing, evaluate the effects of right ventricular septal pacing,including the synchronism of right and left ventricular depolarization,the pathway of ventricular activation,the sequence of ventricular activation and the ventricular depolarization vector,explore the reasons that RVS pacing has more advantages than RVA pacing.Thereby,to direct the selection of fight ventricular lead placement.Methods:Analysis was done in 68 cases with permanent pacemaker implantation,38 male and 30 female,the mean age was 68.66~8.64.Recorded the common 12 leads electrocardiogram preoperatively,separated them into RVS group 31 cases and RVA group 37 cases according to the ventricular lead placement.We measured the QRS wave of pacemaker electrocardiogram between these two groups,including the time from pacing signal to depolarization(S-D),the time from pacing signal to the top of R wave(S-R),and the time of QRS duration(QRSd).We calculated the time from depolarization to the top of R wave(D-R),and the time from the top of R wave to the end of depolarization(R-E).We analyzed the QRS main wave directions in the frontal plane,and the transfer of R wave in the chest plane.To aim directly at RVS pacing,we measured and compared the time of S-D S-R QRSd D-R and R-E,analyzed the QRS main wave directions ofⅡⅢavF leads and the QRS waveforms ofⅠavL leads between the high level septal pacing and the low level septal pacing.Results:①The QRSd both in RVS and RVA groups are wider significantly than preoperative normal ECG(p＜0.05).②The mean S-D in RVS group is 0.034±0.002s,compared with the RVS group 0.034±0.002s,has no significant difference(p＞0.05);the mean S-R in RVS group 0.077±0.005s is significantly shorten than the RVA group 0.098±0.013s(p＜0.05);the mean QRSd in RVS group 0.116±0.009s is significantly shorten than the RVA group 0.142±0.012s(p＜0.05);the mean D-R in RVS group 0.043±0.005s is significantly shorten than the RVA group 0.063±0.012s(p＜0.05);the mean R-E in RVS group 0.073±0.010s is significantly shorten than the RVA group 0.078±0.010s(p＜0.05).③There are 19 cases(61.29%) who have 5 or more frontal plane electrocardiogram leads which QRS main wave directions can fit to the preoperative normal ECG in the RVS group,there are 0 cases in the RVA group(p＜0.05);there are 28 cases(90.32%) who have the R wave transfer among the 6 leads of the chest plane pacing ECG in the RVS group,there are only 6 cases(16.22%) in the RVA group(p＜0.05).④In the RVS group,there are 25 cases of them are high level septal pacing,and 6 cases of them are low level septal pacing.The mean S-D R-E and QRSd in high level septal pacing group are 0.034±0.002s 0.074±0.010s 0.115±0.009s,compared with the RVS group 0.034±0.002s 0.071±0.007s 0.118±0.006s,have no significant differences(p＞0.05);the mean S-R D-R in high level septal pacing group are 0.076±0.005s 0.041±0.005s,compared with the RVS group 0.081±0.003s 0.048±0.002s,have significant differences(p＜0.05).All cases(100%) of the high level septal pacing group have positive QRS main wave direction ofⅡⅢavF leads,there are only 2 cases in the low level septal pacing group(p＜0.05).The cases who are the septum of fight ventricular outflow tract(RVOT) pacing in the whole RVS group,mostly have the QS-type QRS waveform of I avL leads,the specificity is 100.00%and the sensitivity is 77.78%.Conclusion:The RVS pacing,compared with RVA pacing,is more beneficial to the synchronism of the Bi-ventricular depolarization,especially the high level septal pacing,the pathway of ventdcular activation,the sequence of ventricular activation and the ventricular depolarization vector are more closer to physiology.Therefore,the RVS pacing can keep a better hemodynamics and heart function.The RVS pacing is more ideal and more physiological pacing.