What are the baseline clinical, electrocardiographic, and echocardiographic predictors of unsuccessful left bundle branch area pacing (LBBAP)?
A novel prediction model incorporating nonspecific intraventricular conduction delay, septal hypertrophy, and right atrial enlargement can effectively estimate the risk of unsuccessful left bundle branch area pacing to optimize patient selection.
ABSTRACT Introduction Left bundle branch area pacing (LBBAP) has rapidly become a preferred form of cardiac physiologic pacing; however, predictors of unsuccessful implantation remain unclear. Methods and Results Between April 2020 and March 2024, LBBAP was attempted in 145 patients. Procedural success was defined by ≥ 1 of the following: output‐dependent QRS morphology changes, V6 R‐wave peak time (RWPT) < 75 ms, V6–V1 interpeak interval ≥ 44 ms, or concordance between intrinsic and paced V6 RWPT derived from left bundle potentials. Baseline clinical, electrocardiographic, and echocardiographic variables were compared between success ( n = 126, 86.9%) and failure ( n = 19, 13.1%) groups. Multivariable logistic regression using Firth's penalized likelihood identified nonspecific intraventricular conduction delay (NIVCD) (odds ratio OR = 4.34; p = 0.02), interventricular septal thickness (IVSd) (OR = 1.39 per mm; p = 0.03), and right atrial area (RAA) (OR = 1.12 per cm 2 ; p = 0.01) as independent predictors of unsuccessful LBBAP. A model integrating these variables demonstrated strong discrimination (area under the curve AUC = 0.84), which was confirmed by bootstrap validation (AUC = 0.85; 95% confidence interval = 0.76–0.93). A nomogram was constructed to enable individualized risk estimation. Conclusion NIVCD, septal hypertrophy, and right atrial enlargement are independent predictors of LBBAP failure. The resulting validated prediction model and nomogram provide individualized pre‐procedural risk estimation and may assist in optimizing patient selection and procedural strategy.
Okubo et al. (Sat,) studied this question.