Author + information
- Received January 8, 2018
- Revision received March 9, 2018
- Accepted March 22, 2018
- Published online August 20, 2018.
- Junaid A.B. Zaman, MA, BMBCha,
- Kelvin Chua, MDa,
- Ali A. Sovari, MDa,
- Bruce Gunderson, MSb,
- Eli S. Gang, MDa,
- Sylvain Ploux, MDc and
- Charles D. Swerdlow, MDa,∗ ()
- aCardiac Electrophysiology, Cedars-Sinai Heart Center, Cedars-Sinai Medical Center, Los Angeles, California
- bMedtronic PLC, Mounds View, Minnesota
- cHôpital Cardiologique du Haut-Lévêque, CHU Centre Hospitalier Universitaire, Bordeaux, Université Bordeaux, L'Institut de RYthmologie et Modélisation Cardiaque, Bordeaux, France
- ↵∗Address for correspondence:
Dr. Charles D. Swerdlow, Cedar-Sinai Heart Center, Cedars-Sinai Medical Center, 414 North Camden Drive, Suite 1100, Beverly Hills, California 90210.
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.
Dr. Zaman was supported by British Heart Foundation, Fulbright Commission. Mr. Gunderson is an employee of and holds stock in Medtronic. Dr. Swerdlow has consulted for Medtronic; and has received honoraria for teaching at Medtronic and Boston Scientific. All other authors have reported that they have no relationships with industry relevant to the contents of this paper to disclose.
Drs. Zaman, Chua, and Sovari contributed equally to this work and are joint first authors.
All authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the JACC: Clinical Electrophysiology author instructions page.
- Received January 8, 2018.
- Revision received March 9, 2018.
- Accepted March 22, 2018.
- 2018 American College of Cardiology Foundation
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