Prognostic impact of lead tip position confirmed via computed tomography in patients with right ventricular septal pacing.

Background: Although fluoroscopy-guided right ventricular (RV) lead placement in the ventricular septum is a widely performed procedure, variation in true RV lead tip position confirmed via computed tomography (CT) and its prognostic implications in patients with atrioventricular block (AVB) are not well understood.
Objective: The purpose of this study was to evaluate the prognostic impact of CT-confirmed RV lead tip position.
Methods: We retrospectively enrolled 228 consecutive patients (age 77 ± 10 years; 125 men) with AVB who underwent fluoroscopy-guided RV septal lead implantation and thoracic CT after pacemaker implantation. Patients were classified into septal and free-wall groups according to RV lead tip position. The primary endpoint was the composite outcome of cardiac death and heart failure hospitalization.
Results: The RV lead tip was located at the free wall in 18 patients (8%). The primary endpoint occurred in 37 patients (16%) over median follow-up of 41 months. Electrocardiographic analysis found that R amplitude >0.53 mV in lead I was significantly predictive of free-wall pacing, with sensitivity of 70% and specificity of 77%. Multivariate Cox regression analysis demonstrated that the lead tip in the free wall (hazard ratio 2.93; 95% confidence interval 1.21-7.11; P = .018) was an independent predictor of the primary endpoint.
Conclusion: Fluoroscopy-guided RV lead placement carries potential risk of unexpected RV free-wall pacing and may increase the risk of cardiac death and heart failure-related hospitalization in patients undergoing RV septal pacing due to AVB and receiving thoracic CT for medical reasons.
(Copyright © 2019 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)