Impact of capped and uncapped abandoned leads on the heating of an MR-conditional pacemaker implant.
Magn Reson Med
; 73(1): 390-400, 2015 Jan.
Article
em En
| MEDLINE
| ID: mdl-24436030
ABSTRACT
PURPOSE:
To assess the risk of radiofrequency (RF)-induced heating in patients with MR-conditional pacemaker (PM) systems, in the presence of another lead abandoned from a previous implant.METHODS:
Four commercial pacemaker leads were placed beside a MR-conditional PM system, inside a human trunk simulator. The phantom has been exposed to the RF generated by a 64 MHz body bird-cage coil (whole-body specific absorption rate [SAR] = 1 W/kg) and the induced heating was measured at the tip of the abandoned lead and of the MR-conditional implant. Configurations that maximize the coupling between the RF field and the leads have been tested, as well as realistic implant positions.RESULTS:
Abandoned leads showed heating behaviors that strongly depend on the termination condition (abandoned-capped or saline exposed) and on the lead path (left or right positioning). Given a whole-body SAR = 1 W/kg, a maximum temperature rise of 17.6°C was observed. The presence of the abandoned lead modifies the RF-heating profile of the MR-conditional implant either an increase or a decrease in the induced heating at its lead tip can occur, mainly depending on the relative position of the two leads. Variations ranging from -63% to +69% with respect to the MR-conditional system alone were observed.CONCLUSION:
These findings provide experimental evidence that the presence of an abandoned lead poses an additional risk for the patient implanted with a MR-conditional PM system. Our results support the current PM manufacturers' policy of conditioning the MR compatibility of their systems to the absence of abandoned leads (including leads from MR-conditional implants). From a clinical point of view, in such cases, the decision whether to perform the exam shall be based upon a risk/benefit evaluation, as in the case of conventional PM systems.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Marca-Passo Artificial
/
Queimaduras por Corrente Elétrica
/
Imageamento por Ressonância Magnética
/
Eletrodos Implantados
Tipo de estudo:
Diagnostic_studies
/
Etiology_studies
/
Prognostic_studies
/
Risk_factors_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article