Effect of implantable cardioverter/defibrillator lead placement in the right ventricle on defibrillation energy requirements. A combined experimental and clinical study1

Abstract

Defibrillation efficacy depends on the position of the distal spring electrode in the RV. A septal position significantly reduces the energy requirements compared to a non-septal position. The decrease in energy requirements might be explained by an increase in current flow through the septum and the posterolateral wall of the left ventricle. reserved

Incidence and clinical predictors of low defibrillation safety margin at time of implantable defibrillator implantation

“…Repositioning of the RV lead is a consideration if the initial lead location is not ideal. A distal shock coil far from apex may elevate DFTs [41,42], and implanting the RV lead near septum and apex may lower DFTs [43][44][45]. Adding a shock coil in the middle cardiac vein [46][47][48][49][50] or azygous vein or implanting a subcutaneous array electrode [51][52][53][54] may be a more successful strategy for low DSM patients who failed to convert ventricular fibrillation with maximum delivered energy, especially in right-sided implant patients.…”

Dual- versus single-coil implantable defibrillator leads: review of the literature

“…Furthermore, ''optimal'' placement of the SVC coil is limited due to varying right heart dimension, and the fixed inter-coil spacing in current dual-coil defibrillation lead systems [47][48][49][50].…”

Distal Right Ventricular Coil Position Reduces Defibrillation Thresholds

“…The DFT was significantly increased by 40% with the catheter that had a 2‐cm pullback. Winter et al 18 compared DFTs in 12 pigs with the RV coil of an Endotak lead placed in a septal and lateral free‐wall position, with the order of testing randomized. The DFT was significantly lower with the septal position (21.9 ± 1.1 J vs 31.8 ± 1.2 J, P < 0.05).…”

“…Limited evidence from theoretical models, 14,15 animal studies, 16–19 and human studies 20,21 indicates that a more apical RV coil position may improve DFTs. However, many of these studies are limited by the fact that the location of the RV coil was estimated fluoroscopically 16–21 . As a result, the true anatomic relationship of the RV coil to the apex with different lead positions could not be confirmed.…”