Voltage gradients in transvenous and subcutaneous defibrillation and their risk of myocardial damage

Andres Belalcazar, Wyatt Stahl, Daniel J. Friedman, Tom F. Brouwer, Reinoud E. Knops, Jeanne E. Poole, E. Kevin Heist

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Introduction: Transvenous implantable cardioverter-defibrillator (ICD) shocks have been associated with cardiac biomarker elevations and are thought in some cases to contribute to adverse clinical outcomes and mortality, possibly from myocardium exposed to excessive shock voltage gradients. Currently, there are only limited data for comparison with subcutaneous ICDs. We sought to compare ventricular myocardium voltage gradients resulting from transvenous (TV) and subcutaneous defibrillator (S-ICD) shocks to assess their risk of myocardial damage. Methods: A finite element model was derived from thoracic magnetic resonance imaging (MRI). Voltage gradients were modeled for an S-ICD with a left-sided parasternal coil and a left-sided TV-ICD with a mid-cavity, a septal right ventricle (RV) coil, or a dual coil lead (TV mid, TV septal, TV septal + superior vena cava [SVC]). High gradients were defined as > 100 V/cm. Results: The volumes of ventricular myocardium with high gradients > 100 V/cm were 0.02, 2.4, 7.7, and 0 cc for TV mid, TV septal, TV septal + SVC, and S-ICD, respectively. Conclusion: Our models suggest that S-ICD shocks produce more uniform gradients in the myocardium, with less exposure to potentially damaging electrical fields, compared to TV-ICDs. Dual coil TV leads yield higher gradients, as does closer proximity of the shock coil to the myocardium.
Original languageEnglish
Pages (from-to)1561-1568
Number of pages8
JournalJournal of cardiovascular electrophysiology
Volume34
Issue number7
Early online date2023
DOIs
Publication statusPublished - Jul 2023

Keywords

  • PEA
  • cardiac enzymes
  • defibrillation
  • subcutaneous ICD
  • troponin
  • voltage gradient

Cite this