Dataset Information

A 1.5T MRI-conditional 12-lead electrocardiogram for MRI and intra-MR intervention.

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.

SUBMITTER: Tse ZT

PROVIDER: S-EPMC3976440 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Publications

A 1.5T MRI-conditional 12-lead electrocardiogram for MRI and intra-MR intervention.

Tse Zion Tsz Ho ZT Dumoulin Charles L CL Clifford Gari D GD Schweitzer Jeff J Qin Lei L Oster Julien J Jerosch-Herold Michael M Kwong Raymond Y RY Michaud Gregory G Stevenson William G WG Schmidt Ehud J EJ

Magnetic resonance in medicine 20140301 3

<h4>Purpose</h4>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.<h4>Methods</h4>The sy ...[more]

PMID: 23580148

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Dataset Information

A 1.5T MRI-conditional 12-lead electrocardiogram for MRI and intra-MR intervention.

Purpose

Methods

Results

Conclusion

Publications

A 1.5T MRI-conditional 12-lead electrocardiogram for MRI and intra-MR intervention.

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