Junaid A B Zaman1, Kelvin Chua1, Ali A Sovari1, Bruce Gunderson2, Eli S Gang1, Sylvain Ploux3, Charles D Swerdlow4. 1. Cardiac Electrophysiology, Cedars-Sinai Heart Center, Cedars-Sinai Medical Center, Los Angeles California. 2. Medtronic PLC, Mounds View, Minnesota. 3. Hôpital Cardiologique du Haut-Lévêque, CHU Centre Hospitalier Universitaire, Bordeaux, Université Bordeaux, L'Institut de RYthmologie et Modélisation Cardiaque, Bordeaux, France. 4. Cardiac Electrophysiology, Cedars-Sinai Heart Center, Cedars-Sinai Medical Center, Los Angeles California. Electronic address: swerdlow@ucla.edu.
Abstract
OBJECTIVES: This study sought to develop and evaluate an algorithm for early diagnosis of dislodged implantable cardioverter-defibrillator (ICD) leads. BACKGROUND: Dislodged defibrillation leads may sense atrial and ventricular electrograms (EGMs), triggering shocks in the vulnerable period that induce ventricular fibrillation (VF). METHODS: We developed a 2-step algorithm by using experimental lead dislodgements (LDs) at ICD implantation and a control dataset of newly implanted, in situ leads. Step 1 consisted of an alert triggered by abrupt decrease in R-wave amplitude and increase in pacing threshold. Step 2 withheld therapy based on ventricular EGM evidence of LD identified from experimental LD behavior. We estimated the algorithm's performance using a registry dataset of 3,624 new implantations and an atrial dislodgement dataset of 14 LDs at the atrium. RESULTS: In the registry dataset, the algorithm identified 20 of 21 radiographic LDs (95%) at a median of 11 days before clinical diagnosis. Step 1 had positive predictive values of 57% for radiographic LD and 77% for surgical revision. The false positive rate was 0.4% after step 1 and ≤0.2% after step 2. In the atrial dislodgement dataset, step 1 identified all 14 LDs; step 2 would have prevented inappropriate therapy in all 7 patients with stored EGMs at LD, including 2 patients with fatal, shock-induced VF. CONCLUSIONS: An ICD algorithm can facilitate early diagnosis of defibrillation LD. Additional data are needed to determine the safety of withholding shocks based on EGM evidence of LD.
OBJECTIVES: This study sought to develop and evaluate an algorithm for early diagnosis of dislodged implantable cardioverter-defibrillator (ICD) leads. BACKGROUND: Dislodged defibrillation leads may sense atrial and ventricular electrograms (EGMs), triggering shocks in the vulnerable period that induce ventricular fibrillation (VF). METHODS: We developed a 2-step algorithm by using experimental lead dislodgements (LDs) at ICD implantation and a control dataset of newly implanted, in situ leads. Step 1 consisted of an alert triggered by abrupt decrease in R-wave amplitude and increase in pacing threshold. Step 2 withheld therapy based on ventricular EGM evidence of LD identified from experimental LD behavior. We estimated the algorithm's performance using a registry dataset of 3,624 new implantations and an atrial dislodgement dataset of 14 LDs at the atrium. RESULTS: In the registry dataset, the algorithm identified 20 of 21 radiographic LDs (95%) at a median of 11 days before clinical diagnosis. Step 1 had positive predictive values of 57% for radiographic LD and 77% for surgical revision. The false positive rate was 0.4% after step 1 and ≤0.2% after step 2. In the atrial dislodgement dataset, step 1 identified all 14 LDs; step 2 would have prevented inappropriate therapy in all 7 patients with stored EGMs at LD, including 2 patients with fatal, shock-induced VF. CONCLUSIONS: An ICD algorithm can facilitate early diagnosis of defibrillation LD. Additional data are needed to determine the safety of withholding shocks based on EGM evidence of LD.
Authors: Andreas Haeberlin; Rémi Chauvel; Antoine Noel; Nicolas Welte; Philippe Ritter; Pierre Bordachar; Sylvain Ploux Journal: J Interv Card Electrophysiol Date: 2019-08-24 Impact factor: 1.900