Original Contribution Efficacy of transesophageal defibrillation in ventricular fibrillation of long duration B Karl Mischke MD ⁎ , Thomas Schimpf MD, Christian Knackstedt MD, Christian Eickholt MD, Peter Hanrath MD, Malte Kelm MD, Patrick Schauerte MD Department of Cardiology, RWTH Aachen University, 52074 Aachen, Germany Received 31 March 2007; revised 6 April 2007; accepted 5 May 2007 Abstract Introduction: Increasing duration of ventricular fibrillation (VF) is associated with a higher risk of ineffective resuscitation. In addition, precountershock chest compression can influence defibrillation success. Transesophageal defibrillation may increase defibrillation success because of the proximity of the esophagus to the heart. We evaluated the efficacy of transesophageal defibrillation compared with standard transthoracic defibrillation after long episodes of VF. Methods: Defibrillation success after 10 minutes of untreated VF was evaluated in 12 sheep randomized into 2 groups: (group A) in 6 sheep, up to 3 transthoracic shocks were applied, followed by up to 3 transesophageal shocks (first shock: 150 J, second and third shocks: 200 J). (group B) In 6 sheep, 2 minutes of precountershock chest compression preceded the defibrillation shocks. Truncated biphasic shocks were delivered between a sternal and an apical patch electrode for transthoracic defibrillation and between an esophageal and a cutaneous patch electrode for transesophageal defibrillation. Results: In group A with no precountershock chest compression, external defibrillation failed despite shocks with maximum energy (200 J) in all 6 sheep. Transesophageal defibrillation was successful in 3 sheep (50%). In group B with precountershock chest compression, external defibrillation failed in all 6 sheep. Transesophageal defibrillation was successful with the first shock in all 6 sheep. Conclusions: Transesophageal defibrillation may terminate VF of long duration that is refractory to standard defibrillation. Precountershock chest compression may increase transesophageal defibrillation success. © 2008 Elsevier Inc. All rights reserved. 1. Introduction The time to defibrillation is critical with regard to surviving ventricular fibrillation (VF) [1]. Although public access to automatic external defibrillators has somewhat ☆ Funding and materials were provided by Philips Medical Systems, Andover, Mass. P Hanrath and P Schauerte hold a patent for single-use sheaths for transesophageal cardioversion/defibrillation. ⁎ Corresponding author. Tel.: +49 241 8089669; fax: +49 214 8082414. E-mail address: kmischke@ukaachen.de (K. Mischke). www.elsevier.com/locate/ajem 0735-6757/$ – see front matter © 2008 Elsevier Inc. All rights reserved. doi:10.1016/j.ajem.2007.05.017 American Journal of Emergency Medicine (2008) 26, 287–290