Long-term echocardiographic impact of new regional wall motion abnormalities following left bundle branch area pacing
M Asami, Y Enomoto, J Yamamoto, T Shimizu, N Sahara, K Nakamura, T Sakai, H HaraAbstract
Background
Data on new regional wall motion abnormalities (RWMA) after left bundle branch area pacing (LBBAP) are scarce, and their long-term impact on cardiac function remains uncertain.
Purpose
To investigate the incidence of RWMA detected immediately after LBBAP and their influence on left ventricular function over a 3-year follow-up.
Methods
In this retrospective single-center observational study, 40 of 95 consecutive patients who underwent LBBAP between June 2019 and May 2021 and had routine echocardiography at 3 years were analyzed. Patients were divided according to the presence or absence of RWMA on post-implant echocardiography. Baseline characteristics, pacing parameters, and left ventricular ejection fraction (LVEF) were compared between groups.
Results
Among 40 patients (mean age 77.7 ± 10.6 years; 95% with atrioventricular block), 5 (14.3%) exhibited new RWMA immediately after implantation—anteroseptal in 4 (10%) and diffuse hypokinesis in 1 (2.5%). Median LVEF was 62.5% (43.9–73.7) post-implant and 61.0% (38.7–75.6) at 3 years (p = 0.74). Patients with RWMA had significantly lower LVEF at 3 years than those without (51.7% [45.8–63.1] vs. 61.2% [38.7–75.6], p = 0.03). Mean ventricular pacing ratio at follow-up was 97.7% ± 5.6.
Conclusion
RWMA occurred in approximately 14% of patients following LBBAP and were associated with reduced long-term LVEF. These findings suggest possible localized myocardial injury or mechanical dyssynchrony at the pacing site, highlighting the importance of echocardiographic surveillance after LBBAP.