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Introduction: Left bundle branch area pacing (LBBAP) is achieved by advancing the lead tip deep in the septum. Most LBBAP implants are performed using the Medtronic SelectSecure™ MRI SecureScan™ Model 3830 featuring a unique 4 Fr fixed helix lumenless design. Details of lead use conditions and long‐term reliability have not been reported. This study was designed to quantify the mechanical use conditions for the 3830 lead during and after LBBAP implant, and to evaluate reliability using bench testing and simulation. Methods: Fifty bradycardia patients with implantation of the 3830 lead for LBBAP were enrolled. Use conditions of lead deployment at implantation were collected and computed tomography (CT) scans were performed at 3‐month follow‐up. Curvature amplitude along the pacing lead was determined with CT images. Fatigue bending was performed using accelerated testing in a more severe environment than routine clinical use conditions. Conductor fracture rate in a simulated patient population was estimated based on clinical use conditions and fatigue test results. Results: The number of attempts to place the 3830 lead for LBBAP was 2.1 ± 1.3 (range: 1–7) with 13 ± 6 lead rotations at the final attempt. Extreme implant conditions were simulated in bench testing with 5 applications of 20 turns followed by up to 400 million bending cycles. Reliability modeling predicted a 10‐year fracture rate of 0.02%. Conclusions: LBBAP implants require more lead rotations than standard pacing implants and result in unique lead bending. Application of simulated LBBAP use conditions to the 3830 lead in an accelerated in‐vitro model does not produce excess conductor fractures. IMAGE‐LBBP Study ID of ClinicalTrial.GOV: NCT04119323. [ABSTRACT FROM AUTHOR]

Introduction: Left bundle branch area pacing (LBBAP) is a novel physiological pacing modality. The relationship between the pacing lead tip location and paced electrocardiographic (ECG) characteristics remains unclear. The objectives are to determine the lead tip location within the interventricular septum (IVS) and assess the location‐based ECG QRS duration (QRSd) and left ventricular activation time (LVAT). Methods: This multicenter study enrolled 50 consecutive bradycardia patients who met pacemaker therapy guidelines and received LBBAP implantation via the trans‐ventricular septal approach. After at least 3 months postimplant, 12‐lead ECGs and pacing parameters were obtained. Cardiac computed tomography (CT) imaging was performed to assess the LBBAP lead tip distance from the LV blood pool. Results: Among the 50 patients, analyzable CT images were obtained in 42. In 23 of the 42 patients, the lead tips were within 2 mm to the LV blood pool (the LV subendocardial (LVSE) group), 13 between 2 and 4 mm (the Near‐LVSE group), and the remaining 6 beyond 4 mm (the Mid‐LV septal (Mid‐LVS) group). No significant differences in paced QRSd were found among the three groups (LVSE, 107 ± 15 ms; Near‐LVSE, 106 ± 13 ms; Mid‐LVS, 104 ± 15 ms; p =.87). LVAT in the LVSE (64 ± 7 ms) was significantly shorter than in the Mid‐LVS (72 ± 8 ms; p <.05), but not significantly different from that in the Near‐LVSE (69 ± 8 ms; p >.05). Conclusion: In routine LBBAP practice, paced narrow QRSd and fast LVAT, indicative of physiological pacing, were consistently achieved for lead tip location in the LV subendocardial or near LV subendocardial region. [ABSTRACT FROM AUTHOR]

Introduction: Left bundle branch pacing (LBBP) is characterized with a low and stable pacing capture threshold, relatively narrow QRS duration due to fast left ventricular activation, and direct excitation of the diseased left bundle branch. This report aims to describe the methods, procedural skills, and clinical implications of performing LBBP implantation. Methods and Results: LBBP is achieved by transventricular‐septal approach. There are two methods to identify the location for LBBP lead placement: the single‐lead method and the dual‐lead method. During implantation, the unique transition of the paced QRS morphology and pacing parameter changes are important for guiding the lead ‐ advancement to the left side of the interventricular septum. In our experience, LBBP can be safely performed in most patients requiring pacemaker therapy. Conclusion: Clinical development of LBBP is at an early but encouraging phase with increasing clinical use, and a standardized procedure with improved delivery tools and pacing leads is needed, as well as long‐term efficacy and safety. [ABSTRACT FROM AUTHOR]

A 57‐year‐old male presented with symptomatic systolic heart failure and complete left bundle branch block (LBBB). Left bundle branch pacing corrected LBBB at a low capture threshold (0.5V @0.4ms) with right bundle branch conduction delay and paced QRS morphology changed to near‐normal by adjusting AV delay with diminished RBBD. At 1‐year follow‐up, the patient had a significant improvement in heart failure and LBBB automatically resolved with a rate‐dependent pattern. LBBP may be an alternative to conventional cardiac resynchronization therapy with the likelihood of recovery of LBBB. More research is needed to evaluate the potential use of this pacing strategy in patients with LBBB and heart failure. [ABSTRACT FROM AUTHOR]

The cover image is based on the Original Article Clinical use conditions of lead deployment and simulated lead fracture rate in left bundle branch area pacing by Jiangang Zou MD et al., https://doi.org/10.1111/jce.15843. [ABSTRACT FROM AUTHOR]

Preventive Effectiveness of Implantable Cardioverter. Introduction: This prospective and multicenter trial of the implantable cardioverter-defibrillator (ICD) aimed to evaluate the mortality rate (including sudden cardiac death [SCD]) and the efficacy of ICD in Chinese patients with high risk of sudden death. Methods and Results : This trial was conducted in 31 centers in China. We enrolled 497 patients who fulfilled Class I indication for ICD (2002 ACC/AHA/NASPE guideline). All patients were followed-up at 3, 6, and 12 months. Clinical characteristics and echocardiographic parameters were collected at baseline and follow-up; Kaplan-Meier survival analysis was performed. Among 497 enrolled patients with Class I indication of ICD therapy, 112 (22.5%) agreed to and received ICD implantation (ICD group). The remaining 385 patients who were not available for ICD therapy were designated as the non-ICD group. During a mean follow-up of 11 ± 3 months, there were a total of 38 deaths, 2 in the ICD group with a mortality of 1.8% and 36 in the non-ICD group, with a mortality of 9.4% and 26 due to SCD. The overall survival rate was 93% at 3 months of follow-up, 91% at 6 months, and 89% at 12 months, with an incidence of SCD of 5%, 7%, and 8% at 3, 6, and 12 months, respectively. Conclusions : In patients with Class I indication of ICD implantation, the total mortality and incidence of SCD were high. ICD therapy can effectively reduce the mortality in such patients. (J Cardiovasc Electrophysiol, Vol. 23, pp. S5-S9, November 2012) [ABSTRACT FROM AUTHOR]