Clinical Application Of Left Ventricular Quadrupole In Cardiac Resynchronization Therapy

Objective:The present study aims to demonstrate the safety and efficacy of the quadripolar lead implantation.Methods:A series of consecutive heart failure patients undergoing de novo CRT implantation with a quadripolar left ventricular(LV)lead(QuartetTM 1458Q,St.Jude Medical,USA)were enrolled from September 2013 to September 2015 in National centre of cardiovascular disease,China.We collected demographic and clinical data and device related clinical events at implant,before discharge,and at 6-month follow-up.The efficacy of CRT with the quartet lead was assessed by echocardiography and New York Heart Association classification.Results:A total of 24 consecutive heart failure patients(70.8%men;age 54.69±9.4 years;LV ejection fraction 28%±4%;QRS duration 163.8±23.5ms)were included in this study.Although 4 patients(16.7%)presented significant phrenic nerve stimulation(PNS)or high LV pacing thresholds(HPT)by using the conventional pacing configuration,the implantation of the quadripolar LV lead overcame these problems and led to a 100%implant success rate by reprograming the additional vectors.During the follow-up,we observed 1 case of LV lead dislodgement,1 pocket hematomas,4 clinical PNS and 2 HPT(?3V/lms),all were eliminated by reprogramming the device.At 6-month follow-up,LVEF significantly increased from 28%±5%to 38%± 11%(P<0.001).Overall,17 patients(70.8%)were CRT responders as assessed by 6-month echocardiography,and 16 patients(66.7%)improved by at least one level in New York Heart Association(NYHA)class.Conclusions:The implantation of quadripolar LV lead in heart failure patient is feasible with a high implant success rate,a low rate of device complication as well as a high CRT response rate during 6-month follow-up.Objective:This study aimed to evaluate the acute and 3-month availability of viable LVPSs provided by a quadripolar LV pacing lead.Methods:A single-center cohort study evaluated consecutive patients who underwent a CRT implant with the QuartetTM LV lead under local guidelines.The availability of viable LVPSs was assessed at the pre-discharge and 3-month follow-up visit.Bipolar lead configurations,served as the control group,were modeled by eliminating the two proximal electrodes on the QuartetTM LV lead.Results:A total of 24 patients were enrolled and finished 3-month follow-up.The mean follow-up period was 93±3 days.At pre-discharge,the QuartetTM LV lead provided more viable LVPSs compared with the bipolar equivalents(median 3[IQR 2-4]VS median 2[IQR 1-2],P<0.001).The percentage of patients with at least 1,2,3,and 4 viable LVPSs were 100%(24/24),91.7%(22/24),58.3%(14/24)and 33.3%(8/24)for QuartetTM leads and 91.7%(22/24),70.8%(17/24),0%(0/24)and 0%(0/24)for bipolar lead configurations,respectively.The median and IQR values of viable LVPSs provided by the QuartetTM LV lead remained the same(3[IQR 2-4])between pre-discharge and 3-month follow-up(P=0.45).Conclusions:Compared with the bipolar equivalent,QuartetTM LV lead provides more viable LVPSs.The number of LVPSs provided by QuartetTM leads remained unchanged between pre-discharge and 3-month follow-up.Objective:This study aimed to investigate whether dynamic optimizing left ventricular pacing configurations(LVPC)with quadripolar leads can improve response to cardiac resynchronization therapy(CRT).Methods:Fifty-two eligible patients were enrolled and 1:1 randomized to either the quadripolar LV leads(QUAD)group or the conventional bipolar leads(CONV)group.In the QUAD group,optimization of LVPC was performed for all patients before discharge and for nonresponders at 3-month follow-up.Clinical evaluations and transthoracic echocardiograms were performed before,3-and 6 months after CRT implantation.Results:At 3-month follow-up,16 of 25(64%)patients in the CONV group(one patient was lost to follow-up)and 18 of 26(69%)patients in the QUAD group were classified as responders.After optimizing the LVPCs in 3-month nonresponders in QUAD group,21 of 26(80.8%)patients in the QUAD group were classified as responders at 6 months as compared with 17 of 25(68%)patients in the CONV group.ESV reduction,LVEF increase and NYHA functional class reduction at 6 months were significantly greater in the QUAD group than in the CONV group(ESV:-26.9 ± 13.8 vs.-17.2 ± 13.3%,P = 0.013;LVEF:+12.7 ± 8.0 vs.+7.8 ± 6.3 percentage points,P =0.017;NYHA:-1.27 ± 0.67 vs.-0.72 ± 0.54 functional classes,P = 0.002).Conclusions:Compared with conventional bipolar leads,CRT using quadripolar leads with dynamic optimized LVPCs resulted in an additional increase in LVEF and reduction in ESV and NYHA functional class at 6-month follow-up.