PO-05-084 MANAGEMENT OF GRADUAL ELEVATED SHOCK IMPEDANCE IN ENDOTAK RELIANCE ICD LEADS

Elevated shock impedance might indicate structural compromise to implantable cardioverter-defibrillator (ICD) leads. Defibrillation or can be measured in two ways: through high output therapy termed true (TSI); a calculated value using low voltage sub-threshold measurement (LVSM). We have identified 3 cases of gradual LVSM rises (>130 ohm) patients with Endotak Reliance ICD leads at our institution who subsequently had an open circuit fault code commanded TSI testing. Literature search revealed case series (Hauser RG et al 2020 and Monkhouse C 2019) highlighting this phenomenon. sought understand the scope establish potential recommendations for testing by reviewing reported FDA Manufacturer User Facility Device Experience (MAUDE) database. searched MAUDE database from 2008 2021 “high impedance” “impedance problem” while filtering Of these 1369 patients, we those underwent The 117 (majority > 125 that DFT shock. those, 69 (59%) successful what was deemed as acceptable after remain service. 18 dual coil (15%) vector change prior 16 (87%) remaining 30 (26%) code, continued failed defibrillation These were extracted abandoned new implanted. 1 death complication lead extraction. show rise although etiology is uncertain. Potential theories include fibrotic encapsulation calcification SVC/RV coil. It important are identified, monitored, risk stratified. recommend high-risk above range. If within normal limits during testing, surveillance suffice repeat if further increase observed. remains elevated then replacement should considered.