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Background: Tpeak-Tend interval (TpTe), a measurement of transmural dispersion of repolarization (TDR), has been shown to predict ventricular tachyarrhythmia in cardiac resynchronization therapy with defibrillator (CRT-D) patients. However, the ability of TpTe to predict ventricular tachyarrhythmia and mortality for heart failure patients with a cardioverter-defibrillator (ICD) is not clear. The purpose of this study was to assess the predictive ability of TpTe in heart failure patients with ICD., Methods and Results: We enrolled 318 heart failure patients treated after ICD. Patients were divided into 3 groups according to their post-implantation TpTe values and were evaluated every 6 months. The primary endpoint was appropriate ICD therapy. The secondary endpoint was all-cause mortality. During long-term follow-up, the TpTe > 110 ms group (n = 111) experienced more VT/VF episodes (45%) and all-cause mortality (25.2%) than the TpTe 90-110 ms group (n = 109) (26.4%, 14.5%) and TpTe < 90 ms group (n = 98) (11.3%, 11.3%) (overall P < .05, respectively). In Cox regression, longer post-implantation TpTe was associated with an increased number of VT/VF episodes [HR: 1.017; 95% CI: 1.008-1.026; P < .001], all-cause mortality [HR: 1.015; 95% CI: 1.004-1.027; P = .010] and the combined endpoint [HR: 1.018; 95%CI: 1.010-1.026; P < .001]., Conclusions: Post-implantation TpTe was an independent predictor of both ventricular arrhythmias and all-cause mortality in heart failure patients with an implanted ICD.

Background: This study aimed to investigate whether repetitive optimizing left ventricular pacing configurations (LVPCs) with quadripolar leads (QUAD) 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 months follow-up. Clinical evaluations and transthoracic echocardiograms were performed before, 3, and 6 months after CRT implantation., Results: At 3 months follow-up, 16 of 25 (64%) patients in the CONV group (1 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 the 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. Left ventricular end-systolic volume (LVESV) reduction, left ventricular ejection fraction (LVEF) increase, and New York Heart Association (NYHA) functional class reduction at 6 months were significantly greater in the QUAD group than in the CONV group (LVESV: -26.9 ± 13.8 vs -17.2 ± 13.3%; P = .013; LVEF: +12.7 ± 8.0 vs +7.8 ± 6.3 percentage points; P = .017; NYHA: -1.27 ± 0.67 vs -0.72 ± 0.54 functional classes; P = .002)., Conclusions: Compared with conventional bipolar leads, CRT using quadripolar leads with repetitive optimized LVPCs resulted in an additional increase in LVEF and reduction in LVESV and NYHA functional class at 6-month follow-up.

BACKGROUND Whether quadripolar leads can provide sufficient viable left ventricular pacing sites (LVPSs) for device optimization and multipoint pacing remains unclear. This study aimed to evaluate the acute and 3-month availability of viable LVPSs provided by a quadripolar LV pacing lead. MATERIAL AND 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, which served as the control group, were modeled by eliminating the 2 proximal electrodes on the Quartet™ 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 Quartet™ 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 Quartet™ 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 Quartet™ 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 and opportunities for CRT optimization and multipoint LV pacing. The number of LVPSs provided by Quartet™ leads remained unchanged between pre-discharge and 3-month follow-up.

Background: Prolongation of the Tpeak-Tend (TpTe) interval as a measurement of transmural dispersion of repolarization (TDR) is an independent risk factor for chronic heart failure mortality. However, the cardiac resynchronization therapy's (CRT) effect on TDR is controversial. Therefore, this study aimed to evaluate CRTs acute and chronic effects on repolarization dispersion. Furthermore, we aimed to investigate the relationship between TpTe changes and ventricular arrhythmia., Methods: The study group consisted of 101 patients treated with CRT-defibrillator (CRT-D). According to whether TpTe was shortened, patients were grouped at immediate and 1-year follow-up after CRT, respectively. The echocardiogram index and ventricular arrhythmia were observed and compared in these subgroups., Results: For all patients, TpTe slightly increased immediately after CRT-D implantation, and then decreased at the 1-year follow-up (from 107 ± 23 to 110 ± 21 ms within 24 h, to 94 ± 24 ms at 1-year follow-up, F = 19.366,P< 0.001). No significant difference in the left ventricular reverse remodeling and ventricular tachycardia/ventricular fibrillation (VT/VF) episodes between the TpTe immediately shortened and TpTe immediately nonshortened groups. However, patients in the TpTe at 1-year shorten had a higher rate of the left ventricular (LV) reverse remodeling (65% vs. 44%, χ2 = 4.495, P = 0.038) and less VT/VF episodes (log-rank test, χ2 = 10.207, P = 0.001) compared with TpTe 1-year nonshortened group. TpTe immediately after CRT-D independently predicted VT/VF episodes at 1-year follow-up (hazard ratio [HR], 1.030; P = 0.001)., Conclusions: Patients with TpTe shortened at 1-year after CRT had a higher rate of LV reverse remodeling and less VT/VF episodes. The acute changes of TpTe after CRT have minimal value on mechanical reverse remodeling and ventricular arrhythmia.