Improved all-cause mortality with left bundle branch area pacing compared to biventricular pacing in cardiac resynchronization therapy: a meta-analysis.

BACKGROUND: Left bundle branch area pacing (LBBAP) has emerged as a physiological alternative pacing strategy to biventricular pacing (BIVP) in cardiac resynchronization therapy (CRT). We aimed to assess the impact of LBBAP vs. BIVP on all-cause mortality and heart failure (HF)-related hospitalization in patients undergoing CRT. METHODS: Studies comparing LBBAP and BIVP for CRT in patients with HF with reduced left ventricular ejection fraction (LVEF) were included. The coprimary outcomes were all-cause mortality and HF-related hospitalization. Secondary outcomes included procedural and fluoroscopy time, change in QRS duration, and change in LVEF. RESULTS: Thirteen studies (12 observational and 1 RCT, n = 3239; LBBAP = 1338 and BIVP = 1901) with a mean follow-up duration of 25.8 months were included. Compared to BIVP, LBBAP was associated with a significant absolute risk reduction of 3.2% in all-cause mortality (9.3% vs 12.5%, RR 0.7, 95% CI 0.57-0.86, p < 0.001) and an 8.2% reduction in HF-related hospitalization (11.3% vs 19.5%, RR 0.6, 95% CI 0.5-0.71, p < 0.00001). LBBAP also resulted in reductions in procedural time (mean weighted difference- 23.2 min, 95% CI - 42.9 to - 3.6, p = 0.02) and fluoroscopy time (- 8.6 min, 95% CI - 12.5 to - 4.7, p < 0.001) as well as a significant reduction in QRS duration (mean weighted difference:- 25.3 ms, 95% CI - 30.9 to - 19.8, p < 0.00001) and a greater improvement in LVEF of 5.1% (95% CI 4.4-5.8, p < 0.001) compared to BIVP in the studies that reported these outcomes. CONCLUSION: In this meta-analysis, LBBAP was associated with a significant reduction in all-cause mortality as well as HF-related hospitalization when compared to BIVP. Additional data from large RCTs is warranted to corroborate these promising findings.

Coronary artery complications after left bundle branch area pacing: An increasingly reported issue in the era of physiologic pacing.

Coronary artery lesions related to pacemaker implantation are rare complications. With the increasing adoption of the technique of permanent transseptal pacing of the left bundle branch area pacing (LBBAP), an increase in the incidence of these complications may be expected. We report two cases of coronary lesions after permanent transeptal pacing of the LBBAP: the first with a small coronary artery fistula, and the second with an extrinsic coronary compression. Both complications occurred with stylet-driven pacing leads with extendable helix. In the first case, since the shunt volume was small and no major complications were reported, the patient was treated conservatively with good outcome. The second case required lead repositioning due to acute decompensated heart failure.

Left Bundle Branch Pacing vs Left Ventricular Septal Pacing vs Biventricular Pacing for Cardiac Resynchronization Therapy.

BACKGROUND: Left bundle branch pacing (LBBP) and left ventricular septal pacing (LVSP) are considered to be acceptable as LBBAP strategies. Differences in clinical outcomes between LBBP and LVSP are yet to be determined. OBJECTIVES: The purpose of this study was to compare the outcomes of LBBP vs LVSP vs BIVP for CRT. METHODS: In this prospective multicenter observational study, LBBP was compared with LVSP and BIVP in patients undergoing CRT. The primary composite outcome was freedom from heart failure (HF)-related hospitalization and all-cause mortality. Secondary outcomes included individual components of the primary outcome, postprocedural NYHA functional class, and electrocardiographic and echocardiographic parameters. RESULTS: A total of 415 patients were included (LBBP: n = 141; LVSP: n = 31; BIVP: n = 243), with a median follow-up of 399 days (Q1-Q3: 249.5-554.8 days). Freedom from the primary composite outcomes was 76.6% in the LBBP group and 48.4% in the LVSP group (HR: 1.37; 95% CI: 1.143-1.649; P = 0.001), driven by a 31.4% absolute increase in freedom from HF-related hospitalizations (83% vs 51.6%; HR: 3.55; 95% CI: 1.856-6.791; P < 0.001) without differences in all-cause mortality. LBBP was also associated with a higher freedom from the primary composite outcome compared with BIVP (HR: 1.43; 95% CI: 1.175-1.730; P < 0.001), with no difference between LVSP and BIVP. CONCLUSIONS: In patients undergoing CRT, LBBP was associated with improved outcomes compared with LVSP and BIVP, while outcomes between BIVP and LVSP are similar.

The Emerging Role of Left Bundle Branch Area Pacing for Cardiac Resynchronisation Therapy.

Cardiac resynchronisation therapy (CRT) reduces the risk of heart failure-related hospitalisations and all-cause mortality, as well as improving quality of life and functional status in patients with persistent heart failure symptoms despite optimal medical treatment and left bundle branch block. CRT has traditionally been delivered by implanting a lead through the coronary sinus to capture the left ventricular epicardium; however, this approach is associated with significant drawbacks, including a high rate of procedural failure, phrenic nerve stimulation, high pacing thresholds and lead dislodgement. Moreover, a significant proportion of patients fail to derive any significant benefit. Left bundle branch area pacing (LBBAP) has recently emerged as a suitable alternative to traditional CRT. By stimulating the cardiac conduction system physiologically, LBBAP can result in a more homogeneous left ventricular contraction and relaxation, thus having the potential to improve outcomes compared with conventional CRT strategies. In this article, the evidence supporting the use of LBBAP in patients with heart failure is reviewed.

Quantification of Acute Myocardial Damage Secondary to Implantation of Electrodes for the Left Bundle Branch Area Pacing

ABSTRACT Background: Different from the traditional right ventricular pacing, the left bundle branch area pacing (LBBAP) is accomplished with deeper lead implantation and more attempts. However, myocardial damage is unclear in LBBAP. Objective: The objective of the study was to observe the change of troponin T and explore possible factors associated with greater myocardial damage in LBBAP. Methods: Patients with an indication for pacemaker implantation underwent attempts for LBBAP by transventricular septal method. Levels of troponin T were determined before operation, 12 h and 1 week after the operation. Parameters of intraoperation and follow-up were recorded and analyzed. Results: In total, successful LBBAP was achieved in 126 patients. The levels of troponin T increased significantly at 12 h after the operation compared with those before operation (96.45 ± 11.07 [69.06] vs. 16.59 ± 1.84 [11.92] ng/L, p < 0.001), while there were no significant differences between pre- and post-operative levels at 1 week. Correlation and regression analysis showed that only the number of attempts was an independent factor related to the change of troponin T. During 1 year of follow-up, LBBAP was safe and feasible with few complications. Conclusions: Myocardial damage of LBBAP was clinically significant. The number of attempts was an independent factor related to the myocardial damage.