Effects Of Multi-Site Left Ventricular Pacing On Cardiac Electrical Synchrony And Repolarization Parameters

Objects To Investigate if multi-site left ventricular pacing(MSLV)CRT further decrease the pacing electrocardiogram QRS duration and improve myocardial repolarization parameters compared with traditional biventricular pacing cardiac resynchronization therapy(Bi-V CRT).Methods Patients who meet the newest guidelines of cardiac resynchronization therapy and/or defibrillator(CRT-P/CRT-D)implantation were enrolled.All patients have implanted quadripolar or bipolar left ventricular lead and right ventricular lead.During operation,we set single left ventricular(LV),single right ventricular(RV)and biventricular pacing mode,biventricular pacing including one-site left ventricular and RV(1LV + RV),two-site left ventricular and RV(2LV + RV).Surface 12-lead electrocardiograms are collected and electrocardiogram QRS duration and myocardial repolarization parameters of different pacing modes are analyzed.Results(1)We have collected 86 electrocardiograms,including 21 electrocardiograms of LV,8 electrocardiograms of RV,21 electrocardiograms of 1LV +RVand 18 electrocardiograms of 2LV + RV.(2)Single ventricular pacing(including LV and RV)extended the baseline duration of QRS wave;1LV + RV shorten the baseline QRS duration,but did not reach statistical difference(P = 0.055).2 LV + RV shorten the baseline QRS duration(P = 0.014).Compared with the 1LV + RV,2 LV +RV can further decrease QRS duration(?QRS:-5.57± 12.52 vs-14.94±14.01,P=0.034).(3)Compared with baseline,all pacing modes extended the QTc,JTc and Tp-e interval(P<0.05);and LVpacing to extend the repolarization parameters is most obvious,QTc,JTc and Tp-ec duration of 2LV + RV is same to 1LV + RV(P>0.05).Conclusions Compared with the Bi-V CRT,MSLV CRT can further decrease QRS duration,but cannot reduce myocardial repolarization time.