Tian Fangyan, Weng Haobo, Liu Ao, Liu Wen, Zhang Bei, Wang Yanan, Cheng Yufei, Cheng Shan, Fulati Zibire, Zhou Nianwei, Kong Dehong, Pan Cuizhen, Su Yangang, Xu Nuo, Chen Haiyan, Shu Xianhong
Department of Echocardiography, Zhongshan Hospital, Fudan University, Shanghai Institute of Cardiovascular Disease, Shanghai Institute of Medical Imaging, Shanghai, China; Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Cardiovascular Disease, Shanghai, China; Department of Ultrasound Medicine, The Affiliated Hospital of Guizhou Medical University, Guiyang, China.
Department of Echocardiography, Zhongshan Hospital, Fudan University, Shanghai Institute of Cardiovascular Disease, Shanghai Institute of Medical Imaging, Shanghai, China; Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Cardiovascular Disease, Shanghai, China.
Heart Rhythm. 2024 Apr;21(4):445-453. doi: 10.1016/j.hrthm.2023.12.012. Epub 2023 Dec 24.
The effect of left bundle branch pacing (LBBP) on right ventricular (RV) function is not well known, and there is conflicting evidence regarding whether cardiac resynchronization therapy improves RV function.
The study aimed to investigate the effect of LBBP on RV function and to evaluate the response of RV dysfunction (RVD) to LBBP.
Sixty-five LBBP candidates were prospectively included in the study and underwent echocardiography at baseline and 6-month follow-up. LBBP response was left ventricular (LV) reverse remodeling, defined as a reduction in LV end-systolic volume of ≥15% at follow-up.
Patients were assigned to 2 subgroups on the basis of 3-dimensional echocardiography-derived RV ejection fraction (EF) before LBBP implantation: 30 patients (46%) in the no RVD group and 35 patients (54%) in the RVD group. The RVD group was characterized by higher N-terminal pro-brain natriuretic peptide levels, New York Heart Association functional class, and larger LV/RV size. LBBP induced a significant reduction in QRS duration, LV size, and improvement in LVEF and mechanical dyssynchrony in both the no RVD and RVD groups, and a significant improvement in RV volumes and RVEF in the RVD group (all P<.01). LBBP resulted in a similar percentage reduction in QRS duration, LV dimensions, LV volumes, and percentage improvement in LVEF in RVD and no RVD groups (all P＞.05). LV reverse remodeling (29 of 35 patients vs 27 of 30 patients; P = .323) in the RVD group was similar to that in the no RVD group after LBBP.
LBBP induces excellent electrical and mechanical resynchronization, with a significant improvement in RV volumes and function. RVD did not diminish the beneficial effects on LV reverse remodeling after LBBP.
左束支起搏（LBBP）对右心室（RV）功能的影响尚不明确，关于心脏再同步治疗是否能改善RV功能也存在相互矛盾的证据。
本研究旨在探讨LBBP对RV功能的影响，并评估RV功能障碍（RVD）对LBBP的反应。
前瞻性纳入65例LBBP候选患者，在基线和随访6个月时进行超声心动图检查。LBBP反应为左心室（LV）逆向重构，定义为随访时LV收缩末期容积减少≥15%。
根据LBBP植入前三维超声心动图得出的RV射血分数（EF），将患者分为2个亚组：无RVD组30例（46%），RVD组35例（54%）。RVD组的特点是N末端脑钠肽前体水平、纽约心脏协会功能分级较高，LV/RV尺寸较大。LBBP使无RVD组和RVD组的QRS时限、LV大小均显著降低，LVEF和机械不同步性均得到改善，RVD组的RV容积和RVEF也显著改善（均P<.01）。LBBP使RVD组和无RVD组的QRS时限、LV直径、LV容积降低的百分比以及LVEF改善的百分比相似（均P＞.05）。LBBP后，RVD组的LV逆向重构（35例患者中的29例 vs 30例患者中的27例；P = .323）与无RVD组相似。
LBBP可诱导良好的电和机械再同步，显著改善RV容积和功能。RVD并未削弱LBBP后对LV逆向重构的有益作用。
