It is well recognized that a high burden of right ventricular pacing results in deleterious clinical outcomes over the long term. His bundle pacing can achieve optimal ventricular synchronization; however, relatively high pacing thresholds, low R-wave amplitudes, and the long-term performance have been concerns. Recently, left ventricular (LV) septal endocardium pacing (LVSP) has demonstrated improved acute haemodynamics. Another novel technique of intraseptal left bundle branch pacing (LBBP) via transvenous approach has been adopted rapidly and has demonstrated its feasibility and effectiveness. This article reviews the clinical application and differences between LVSP and LBBP. Compared with LVSP, LBBP has strict criteria for left conduction system capture and lead location. In addition to LV septal capture it also stimulates the proximal left bundle branch, resulting in rapid and physiological LV activation. With a uniformity and standardization of the implant procedure and definitions, it may be possible to achieve widespread application of this form of physiological pacing.
  His-bundle pacing (HBP) can be achieved in either atrial-side HBP (aHBP) or ventricular-side HBP (vHBP). The study compared the pacing parameters and electrophysiological characteristics between aHBP and vHBP in bradycardia patients.
 
  Fifty patients undergoing HBP implantation assisted by visualization of the tricuspid valvular annulus (TVA) were enrolled. The HBP lead position was identified by TVA angiography. Twenty-five patients were assigned to undergo aHBP and compared with 25 patients who underwent vHBP primarily in a prospective and randomized fashion. Pacing parameters and echocardiography were routinely assessed at implant and 3-month follow-up. His-bundle pacing was successfully performed in 45 patients (90% success rate with 44.4% aHBP and 55.6% vHBP). The capture threshold was lower in vHBP than aHBP at implant (vHBP 1.1 ± 0.5 vs. aHBP 1.4 ± 0.4 V/1.0 ms, P = 0.014) and 3-month follow-up (vHBP 0.8 ± 0.4 vs. aHBP 1.7 ± 0.8 V/0.4 ms, P < 0.001). The R-wave amplitude was higher in vHBP than in aHBP at implant (vHBP 4.5 ± 1.4 vs. aHBP 2.0 ± 0.8 mV, P < 0.001) and at 3-month follow-up (vHBP 4.4 ± 1.5 vs. aHBP 1.8 ± 0.7 mV, P < 0.001). No procedure-related complications and aggravation of tricuspid valve regurgitation were observed in most patients and echocardiographic assessment of cardiac function remained in the normal range in all patients during the follow-up.
 
  This study demonstrates that vHBP features a low and stable pacing capture threshold and high R-wave amplitude, suggesting better pacing mode management and battery longevity can be achieved by HBP in the ventricular side.
 This study demonstrates that vHBP features a low and stable pacing capture threshold and high R-wave amplitude, suggesting better pacing mode management and battery longevity can be achieved by HBP in the ventricular side.
  His-Purkinje system (HPS) pacing, including His bundle (HB) and left bundle branch (LBB) pacing, has emerged as a highlighted topic in recent years. Comparisons in lead performance and clinical outcomes between HB and LBB pacing were seldom reported. We aimed to investigate the mid-long-term lead performance and clinical outcomes of permanent HPS pacing patients in our centre.
 
  Permanent HB pacing was implemented by placing the pacing lead helix at the HB area. Left bundle branch pacing was achieved by placing the lead helix in the left-side sub-endocardium of the interventricular septum. Pacing parameters, 12-lead ECG, echocardiography, and clinical outcomes were evaluated during follow-up.  https://www.selleckchem.com/products/LAQ824(NVP-LAQ824).html  A total of 64 patients with HB pacing and 185 with LBB pacing were included. Left bundle branch pacing exhibited a slightly longer paced QRS duration than HB pacing (117.7 ± 11.0 vs. 113.7 ± 19.8 ms, P = 0.04). Immediate post-operation, LBB pacing had a significant higher R-wave amplitude (16.5 ± 7.5 vs. 4.3 ± 3.6 mV, e branch pacing showed superior pacing parameters over HB pacing. Lead micro-displacement with changes in paced QRS morphology posts a concern in LBB pacing.
  The present study was to evaluate the feasibility and clinical outcomes of left bundle branch area pacing (LBBAP) in cardiac resynchronization therapy (CRT)-indicated patients.
 
  LBBAP was performed via transventricular septal approach in 25 patients as a rescue strategy in 5 patients with failed left ventricular (LV) lead placement and as a primary strategy in the remaining 20 patients. Pacing parameters, procedural characteristics, electrocardiographic, and echocardiographic data were assessed at implantation and follow-up. Of 25 enrolled CRT-indicated patients, 14 had left bundle branch block (LBBB, 56.0%), 3 right bundle branch block (RBBB, 12.0%), 4 intraventricular conduction delay (IVCD, 16.0%), and 4 ventricular pacing dependence (16.0%). The QRS duration (QRSd) was significantly shortened by LBBAP (intrinsic 163.6 ± 29.4 ms vs. LBBAP 123.0 ± 10.8 ms, P < 0.001). During the mean follow-up of 9.1 months, New York Heart Association functional class was improved to 1.4 ± 0.6 from baseline 2.6 ± 0.6 LV lead placement and a first-line option in selected patients such as those with LBBB and heart failure.
  His-bundle pacing (HBP) combined with atrioventricular node (AVN) ablation has been demonstrated to be effective in patients with atrial fibrillation (AF) and heart failure (HF) during medium-term follow-up and there are limited data on the risk analysis of adverse prognosis in this population. In this study, we aimed to evaluate the long-term performance of HBP following AVN ablation in AF and HF.
 
  From August 2012 to December 2017, consecutive AF patients with HF and narrow QRS who underwent AVN ablation and HBP were enrolled. The clinical and echocardiographic data, pacing parameters, all-cause mortality, and heart failure hospitalization (HFH) were tracked. A total of 94 patients were enrolled (age 70.1 ± 10.5 years; male 57.4%). Acute HBP were achieved in 89 (94.7%) patients with successful permanent HBP combined with AVN ablation in 81 (86.2%) patients. Left ventricular ejection fraction (LVEF) improved from 44.9 ± 14.9% at baseline to 57.6 ± 12.5% during a median follow-up of 3.0 (IQR 2.0-4.4) years (P < 0.