12-Lead ECG Assessment at 0.55T

Motivation: The 12-lead ECG is the standard diagnostic for monitoring rhythm and ischemia during stress. ECG distortion via magnetohydrodynamic effect is proportional to field strength and limits interpretation at 1.5T and 3T. Lower field (0.55T) offers potential improvement. Goal(s): Compare variability in ECGs in at 0.55T, 1.5T and 3.0T and examine changes in ECG morphology at 0.55T in response to ischemia and exercise stress. Approach: ECGs were recorded in: (1) swine at three fields, and at 0.55T during ischemia, and (2) normal human subjects a and during ergometer stress. Results: At 0.55T ECGs remained interpretable at isocenter though some distortion due to MHD persisted. Impact: Low field (0.55T) MRI can provide improved clinical interpretation of 12-Lead ECGs at isocenter due to reduction of magnetohydrodynamic distortion and reduced sensitivity to patient motion as demonstrated in swine with cardiac ischemia and humans undergoing exercise induced stress.