Left bundle branch area pacing in the setting of cardiac amyloidosis: a case series

Abstract Background Cardiac amyloidosis (CA) is a highly prevalent cause of congestive heart failure. It often requires cardiac pacing due atrioventricular conduction (AV) system disorders, often with cardiac resynchronization (CRT) to prevent development/deterioration of left ventricular (LV) dysfu...

Full description

Saved in:
Bibliographic Details
Published in:Europace (London, England) England), 2024-05, Vol.26 (Supplement_1)
Main Authors: Mirizzi, G, Taddeucci, S, Rossi, A, Nesti, M, Panchetti, L, Startari, U, Garibaldi, S, Piacenti, M
Format: Article
Language:English
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Abstract Background Cardiac amyloidosis (CA) is a highly prevalent cause of congestive heart failure. It often requires cardiac pacing due atrioventricular conduction (AV) system disorders, often with cardiac resynchronization (CRT) to prevent development/deterioration of left ventricular (LV) dysfunction. Left bundle branch area pacing (LBBAP) is an emerging alternative to CRT, offering a strict physiological LV activation and very limited use of iodinated contrast. The feasibility of LBBAP in CA is considered limited due to the presence of septal pseudohypertrophy which theoretically limits left-sided conduction system engagement. Purpose To evaluate the feasibility and effectiveness of LBBAP in cardiac amyloidosis. Methods Consecutive patients with CA (both light-chain -AL- or wild-type transtiretin -wtATTr) with a pacing indication for AV conduction disorders were enrolled. Patients underwent baseline echocardiographic examination. LBBAP was achieved by means of stylet-driven leads advanced transeptally (right ventricle (RV) to LV) via dedicated delivery systems, with continuous monitoring of 12-lead electrocardiographic morphology and impedance until a typical QRS morphology in V1 was obtained (usually rSr’ or Sr’). Standard measures for left bundle (LB) capture were used (stimulus to peak R in V6 – S-RV6, V6-V1 interpeak interval, presence of transition in these measures during threshold testing, presence of fascicular signal during spontaneous QRS). Results Between January 2022 and June 2023, among 63 patients undergoing LBBAP, 7 patients (11%) had CA, 2 AL (28%) and 5 (72%) wtATTR. Patients were prevalently old (78±7 y) males (6, 85%); LV mean septal thickness was 17±2 mm (min 16, max 20 mm) and mean LV ejection fraction (LVEF) was 45±6%. Indications were PR prolongation in 3, bradycardic atrial fibrillation and LB branch block (LBBB) in 2, primary LBBB in 1 and chronic RV pacing in 1. Baseline QRS duration was 145±47 ms (QRS120 ms: 182±13 ms). LBBAP success was 100%. Fascicular electrograms were observed in ¾ of patients without LBBB; S-RV6 interval was 74 ±11 ms (³70 ms in 3), RV6-RV1 interpeak interval was 47±9 ms (³ 30 ms in 6 patients). DQRS in baseline broad QRS was -52 ms and +32 ms in narrow. No complications were observed. Over a short follow up of 6 months, an increase in average LVEF was observed (LVEF at 6 months: 51±3%, p
ISSN:1099-5129
1532-2092
DOI:10.1093/europace/euae102.467