A 1.5T MRI-conditional 12-lead electrocardiogram for MRI and intra-MR intervention.
Magn Reson Med
; 71(3): 1336-47, 2014 Mar.
Article
in En
| MEDLINE
| ID: mdl-23580148
ABSTRACT
PURPOSE:
High-fidelity 12-lead electrocardiogram (ECG) is important for physiological monitoring of patients during MR-guided intervention and cardiac MRI. Issues in obtaining noncorrupted ECGs inside MRI include a superimposed magneto-hydro-dynamic voltage, gradient switching-induced voltages, and radiofrequency heating. These problems increase with magnetic field. The aim of this study is to develop and clinically validate a 1.5T MRI-conditional 12-lead ECG system.METHODS:
The system was constructed with transmission lines to reduce radiofrequency induction and switching circuits to remove induced voltages. Adaptive filters, trained by 12-lead measurements outside MRI and in two orientations inside MRI, were used to remove the magneto-hydro-dynamic voltage. The system was tested on 10 (one exercising) volunteers and four arrhythmia patients.RESULTS:
Switching circuits removed most imaging-induced voltages (residual noise <3% of the R-wave). Magneto-hydro-dynamic voltage removal provided intra-MRI ECGs that varied by <3.8% from those outside the MRI, preserving the true S-wave to T-wave segment. In premature ventricular contraction (PVC) patients, clean ECGs separated premature ventricular contraction and sinus rhythm beats. Measured heating was <1.5°C. The system reliably acquired multiphase (steady-state free precession) wall-motion-cine and phase-contrast-cine scans, including subjects in whom 4-lead gating failed. The system required a minimum repetition time of 4 ms to allow robust ECG processing.CONCLUSION:
High-fidelity intra-MRI 12-lead ECG is possible.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Atrial Fibrillation
/
Surgery, Computer-Assisted
/
Electrocardiography
/
Magnetic Resonance Imaging, Interventional
/
Cardiac-Gated Imaging Techniques
Type of study:
Diagnostic_studies
Limits:
Aged
/
Animals
/
Female
/
Humans
/
Male
/
Middle aged
Language:
En
Journal:
Magn Reson Med
Journal subject:
DIAGNOSTICO POR IMAGEM
Year:
2014
Type:
Article
Affiliation country:
United States