A Comparison of the Association of Septal Scar Burden on Responses to LBBAP-CRT and BVP-CRT

Zhongli Chen; Xuan Ma; Sijin Wu; Yuan Gao; Yanyan Song; Minjie Lu; Yan Dai; Shu Zhang; Wei Hua; Michael R Gold; Shihua Zhao; Keping Chen

doi:10.1016/j.jacep.2024.03.005

A Comparison of the Association of Septal Scar Burden on Responses to LBBAP-CRT and BVP-CRT

JACC Clin Electrophysiol. 2024 Apr 16:S2405-500X(24)00186-5. doi: 10.1016/j.jacep.2024.03.005. Online ahead of print.

Authors

Zhongli Chen¹, Xuan Ma², Sijin Wu¹, Yuan Gao², Yanyan Song², Minjie Lu², Yan Dai¹, Shu Zhang¹, Wei Hua¹, Michael R Gold³, Shihua Zhao⁴, Keping Chen⁵

Affiliations

¹ State Key Laboratory of Cardiovascular Disease, Cardiac Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
² Department of Magnetic Resonance Imaging, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
³ Division of Cardiology, Medical University of South Carolina, Charleston, South Carolina, USA.
⁴ Department of Magnetic Resonance Imaging, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. Electronic address: cjrzhaoshihua2009@163.com.
⁵ State Key Laboratory of Cardiovascular Disease, Cardiac Arrhythmia Center, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. Electronic address: chenkeping@263.net.

PMID: 38727661
DOI: 10.1016/j.jacep.2024.03.005

Abstract

Background: Left bundle branch area pacing (LBBAP) is an alternative to biventricular pacing (BVP) for cardiac resynchronization therapy (CRT). However, despite the presence of left bundle branch block, whether cardiac substrate may influence the effect between the 2 strategies is unclear.

Objectives: This study aims to assess the association of septal scar on reverse remodeling and clinical outcomes of LBBAP compared with BVP.

Methods: We analyzed patients with nonischemic cardiomyopathy who had CRT indications undergoing preprocedure cardiac magnetic resonance examination. Changes in left ventricular ejection fraction (LVEF) and echocardiographic response (ER, ≥5% absolute LVEF increase) were assessed at 6 months. The clinical outcome was the composite of all-cause mortality, heart failure hospitalization, or major ventricular arrhythmia.

Results: There were 147 patients included (51 LBBAP and 96 BVP). Among patients with low septal scar burden (below median 5.7%, range: 0 to 5.3%), LVEF improvement was higher in the LBBAP than the BVP group (17.5% ± 10.9% vs 12.3% ± 11.8%; P = 0.037), with more than 3-fold increased odds of ER (odds ratio: 4.35; P = 0.033). In high sepal scar subgroups (≥5.7%, range: 5.7% to 65.9%), BVP trended towards higher LVEF improvement (9.2% ± 9.4% vs 6.4% ± 12.4%; P = 0.085). Interaction between septal scar burden and pacing strategy was significant for ER (P = 0.002) and LVEF improvement (P = 0.011) after propensity score adjustment. During median follow-up of 33.7 (Q1-Q3: 19.8 to 42.1) months, the composite clinical outcome occurred in 34.7% (n = 51) of patients. The high-burden subgroups had worse clinical outcomes independent of CRT method.

Conclusions: Remodeling response to LBBAP and BVP among nonischemic cardiomyopathy patients is modified by septal scar burden. High septal scar burden was associated with poor clinical prognosis independent of CRT methods.

Keywords: biventricular pacing; left bundle branch area pacing; nonischemic cardiomyopathy; prognosis; reverse remodeling; septal scar.