Electromagnetic Interference (EMI) and Arrhythmic Events in ICD Patients Undergoing Gastrointestinal Procedures


Address for reprints: Jeffrey Kluger, M.D., F.A.C.C., Heart Rhythm Management, Hartford Hospital, 80 Seymour Street, Hartford, CT 06102; Fax: +860-545-2756; e-mail: Jkluger@harthosp.org


Background:The objective was to determine the effect of electromagnetic interference (EMI) in patients undergoing gastrointestinal endoscopy. The implantable cardioverter-defibrillator (ICD) is the primary therapeutic modality for patients at risk for sudden cardiac death. One potential problem with ICDs is interactions with electrical devices and medical procedures causing EMI or triggering arrhythmic events. Endoscopy frequently employs electrocautery (EC) for diagnosis and treatment of gastrointestinal diseases. Current guidelines advise inactivating ICDs before any surgical procedure. There is limited information on management of ICDs during endoscopy with or without EC. We prospectively evaluated patients with ICDs undergoing endoscopic procedures at our institution.

Methods and results:Forty-one ICD patients underwent 52 gastrointestinal endoscopies over 17 months. The mean age of the population was 66 years (51–83). There were 28 men and 13 women. Thirteen patients had single chamber devices, 25 had dual chamber devices, and 2 had biventricular ICDs. The mean tachyarrhythmia detection rate programmed was 164.7 bpm (125–188). Eighteen procedures (43.9%) required biopsy, coagulation, or polypectomy. Of these, 10 (55%) required the use of EC. Only unipolar EC with mean current 19.6 mA was used. All ICDs were programmed to detection-only with therapies off. Sensitivity was left at nominal programmed settings. Post procedure interrogation showed no detection of EMI or tachyarrhythmic events.

Conclusions:Our study shows no EMI or arrhythmic events triggered during endoscopic procedures in patients with pectorally implanted transvenous ICDs. Routine practice of programming ICDs off for gastrointestinal procedures may not be necessary. However, larger studies are needed before change in current recommendations.