Department of Cardiology
Parkwest Hospital
Knoxville
TN 37923, USA
Tel: +1 865 691 4850
Fax: +1 865 525 9660
E-mail address: gimbeljr{at}ix.netcom.com
Department of Cardiovascular Medicine
Cleveland Clinic Lerner College of Medicine
of Case Western Reserve University
The Cleveland Clinic Foundation
Cleveland
OH, USA
Department of Radiology
University of Pittsburgh Medical Center
Pittsburgh
PA, USA
Division of Anesthesiology and Critical Care
M D Anderson Cancer Center
The University of Texas
Houston
TX, USA
We were quite concerned reading the recent editorial by Dr Edward T. Martin.1 Some statements are erroneous and some recommendations made are potentially dangerous if followed by the readers of the European Heart Journal.
As earlier,2 Martin overstates the problem of denying device patients MRI. The cited study by Sakakibara and Mitsui3 does not report that 17% of patients with pacemakers were denied MRI in the previous year as stated by Martin. Rather, Sakakibara and Mitsui merely asked, Have you ever had any medical problems for which MRI was recommended; 17.2% of the respondents said, yes.
Echoing Gimbel,4,5 Martin notes, no deaths have been reported during physician supervised MRI procedures. Martin's statement is simply not true as at least four pacemaker patients have died while undergoing physician supervised MRI.6 Importantly, Bartsch et al.6 also note, in all four cases the patients were not pacemaker dependent. Thus, comments made by Martin (and previously Gimbel, made prior to the publication of Bartsch) are untrue. Physicians interested in performing MRI on device patients should note this important fact.
Martin observes that approximately 300 pacemaker patients have safely undergone MRI, although there have been 10 deaths attributed to MR and pacemaker interactions.1 In recommending strategies to facilitate safe MRI of device patients, Martin leaves the pre-MRI reprogramming of the device as optional. This is a (non)strategy, presumably based on the fortunate outcome of the 54 pacemaker patients who underwent MRI with minimal or no device reprogramming under his direction.2 In this EHJ editorial, however, Martin notes that reprogramming the pacemaker to sub-threshold pacing outputs or off... would diminish the potential for the rare episode of ventricular fibrillation.1 If Martin does feel it reduces the risk to the device patient undergoing MRI, we cannot understand, why such a simple reprogramming strategy would not be clearly recommended? Patients have a reasonable expectation that a diagnostic study without therapeutic benefit such as an MRI scan will not cause serious harm to them. Is it not our obligation to make procedures as safe as possible for patients? It should be noted that virtually all investigators except Martin et al., recommend substantial device reprogramming prior to MRI.7,8 The frequent occurrence of demonstrated magnet-mode behaviour during the MRI2 as reported by Martin et al. should not be viewed as benign.6,9,10
We were puzzled that even after recently responding to a Letter to the Editor in the Journal of the American College of Cardiology reporting, among other issues, the unreliability of ECG monitoring during MRI,11 Martin continues to state that pulse oximetry monitoring is not necessary during MRI of a device patient.1 Given the seriousness of the potential complications (death) and the unreliability of ECG monitoring during MRI,7,10,11 we remain perplexed why such a simple safety measure is not recommended as has been by others.7,8,10,12
Martin's mystifying final recommendation to facilitate safe MRI of device patients is scan modern pacemakers (manufactured after 2000). Nevertheless, in their recently reported series (as well as all the pacemaker patients cited in support of his recommendations in Table 1), virtually all of the patients safely scanned by Martin et al. had devices manufactured before 2000. Although not cited specifically, the recently published work by Roguin et al.8 is likely the source of this recommendation. Martin's audience should be reminded that no device manufacturer has claimed MRI device compatibility, irrespective of the manufacture date of the device. Despite a manufacturer's bold announcement of a new and improved device, with a different shape and a clever name stamped on the case, each new device is a derivative and contains multiple legacy components (designed prior to 2000 and without MRI safety as a consideration) that may be adversely affected by exposure to the EMI in the MRI suite.
After reading Martin's editorial, we are reminded of the final thoughts in Achenbach et al.:13 Carelessness or reduced awareness of the potential dangers could cost a patient's life.
References
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