Initial Experience with Intercostal Insertion of an Extravascular ICD Lead Compatible with Existing Pulse Generators

Abstract

Structured AbstractObjectivesThis study assessed safety and feasibility of a novel extravascular (EV) implantable cardioverter-defibrillator (ICD) lead when inserted anteriorly through a rib space and connected to various commercially available ICD pulse generators (PGs) placed in either a left mid-axillary or left pectoral pocket.BackgroundCurrently available or investigational, EV-ICDs include a subcutaneous or subxiphoid lead connected to customized EV-ICD PGs. This novel EV-ICD (AtaCor Medical, Inc, San Clemente, CA) employs a unique intercostal implant technique and is designed to function with commercial DF-4 ICD PGs.MethodsIn this non-randomized, single-center, acute study, 36 de novo or replacement transvenous (TV) ICD patients enrolled to receive a concomitant EV-ICD lead inserted through an intercostal space along the left parasternal margin. EV-ICD leads were connected to DF-4 compatible ICD PGs positioned in either a left mid-axillary or pectoral pocket for acute sensing and defibrillation testing. Defibrillation testing started at 30 Joules (J) and stepped down in 10 J increments following conversion success and stepped up in 5 J increments following conversion failure.ResultsSuccessful acute defibrillation using ≤ 35 J was noted in 100% of left mid-axillary PG subjects (n=27, mean 16.3 ± 8.6 J) and 83% of left pectoral PG subjects (n=6, mean 21.0 ± 8.4 J). All evaluable episodes (n=93) were automatically sensed, detected, and shocked. No serious device-related intraoperative adverse events were observed.ConclusionsThis first-in-human study documented safe and reliable placement of a novel extravascular ICD lead with effective sensing and defibrillation of induced ventricular fibrillation using commercial DF-4 ICD pulse generators.Condensed AbstractThis study assessed feasibility of intercostal implantation of a novel extravascular implantable cardioverter-defibrillator (ICD) lead designed to function with commercial DF-4 pulse generators (PGs). Lead placement was successful in 33 of 36 attempts (94%). Acute defibrillation with ≤35 J was successful in 27 of 27 left mid-axillary PG subjects (100%) and 5 of 6 left pectoral PG subjects (83%). All evaluable episodes (n=93) were automatically detected. No serious device-related intraoperative adverse events were observed. This study demonstrates feasibility of a novel extravascular ICD lead with effective sensing and defibrillating of induced ventricular fibrillation using commercial DF-4 PGs.