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Title: Effect of 1. 5 tesla nuclear magnetic resonance imaging scanner on implanted permanent pacemakers

Abstract

Patients with a permanent pacemaker are currently restricted from diagnostic nuclear magnetic resonance (NMR) imaging because of potential adverse effects on the pacemaker by the magnet. Previous work has shown that NMR imaging will result in asynchronous pacing of the pulse generator within a given distance of the magnet. The radiofrequency signal generated by the system may also result in rapid cardiac pacing, which may have deleterious effects. This study utilized a 1.5 tesla unit in an in vivo laboratory animal to evaluate the unit's effects on eight different pulse generators from two manufacturers. All pacemakers functioned in an asynchronous mode when placed within a certain distance of the magnet. In addition, transient reed switch inhibition was observed. Seven of the eight pulse generators paced rapidly when exposed to the radiofrequency signal and there was a dramatic decrease in arterial blood pressure. Whether effective rapid cardiac pacing would occur could not be predicted before exposure to the magnetic resonance unit. Nuclear magnetic resonance imaging with high magnetic fields in patients with a pacemaker should continue to be avoided until the mechanism of the rapid cardiac pacing can be further delineated and either predicted or prevented.

Authors:
; ;
Publication Date:
Research Org.:
Mayo Clinic, Rochester, MN
OSTI Identifier:
5851484
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Am. Coll. Cardiol.; (United States); Journal Volume: 10:4
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; CARDIAC PACEMAKERS; EVALUATION; HEART; NMR IMAGING; BLOOD PRESSURE; DOGS; NUCLEAR MAGNETIC RESONANCE; ANIMALS; BODY; CARDIOVASCULAR SYSTEM; DIAGNOSTIC TECHNIQUES; MAGNETIC RESONANCE; MAMMALS; ORGANS; RESONANCE; VERTEBRATES; 550600* - Medicine

Citation Formats

Hayes, D.L., Holmes, D.R. Jr., and Gray, J.E. Effect of 1. 5 tesla nuclear magnetic resonance imaging scanner on implanted permanent pacemakers. United States: N. p., 1987. Web. doi:10.1016/S0735-1097(87)80270-X.
Hayes, D.L., Holmes, D.R. Jr., & Gray, J.E. Effect of 1. 5 tesla nuclear magnetic resonance imaging scanner on implanted permanent pacemakers. United States. doi:10.1016/S0735-1097(87)80270-X.
Hayes, D.L., Holmes, D.R. Jr., and Gray, J.E. 1987. "Effect of 1. 5 tesla nuclear magnetic resonance imaging scanner on implanted permanent pacemakers". United States. doi:10.1016/S0735-1097(87)80270-X.
@article{osti_5851484,
title = {Effect of 1. 5 tesla nuclear magnetic resonance imaging scanner on implanted permanent pacemakers},
author = {Hayes, D.L. and Holmes, D.R. Jr. and Gray, J.E.},
abstractNote = {Patients with a permanent pacemaker are currently restricted from diagnostic nuclear magnetic resonance (NMR) imaging because of potential adverse effects on the pacemaker by the magnet. Previous work has shown that NMR imaging will result in asynchronous pacing of the pulse generator within a given distance of the magnet. The radiofrequency signal generated by the system may also result in rapid cardiac pacing, which may have deleterious effects. This study utilized a 1.5 tesla unit in an in vivo laboratory animal to evaluate the unit's effects on eight different pulse generators from two manufacturers. All pacemakers functioned in an asynchronous mode when placed within a certain distance of the magnet. In addition, transient reed switch inhibition was observed. Seven of the eight pulse generators paced rapidly when exposed to the radiofrequency signal and there was a dramatic decrease in arterial blood pressure. Whether effective rapid cardiac pacing would occur could not be predicted before exposure to the magnetic resonance unit. Nuclear magnetic resonance imaging with high magnetic fields in patients with a pacemaker should continue to be avoided until the mechanism of the rapid cardiac pacing can be further delineated and either predicted or prevented.},
doi = {10.1016/S0735-1097(87)80270-X},
journal = {J. Am. Coll. Cardiol.; (United States)},
number = ,
volume = 10:4,
place = {United States},
year = 1987,
month =
}
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