The proper placement of the ECG electrodes in the MRI is critical to reducing the blood flow
induced distortion of the ECG waveform. With proper strategic placement of the ECG electrodes
and minimization of ECG lead cable length, this blood flow induced distortion can be kept to a
minimum, as discussed in this section. Additional artifacts caused by the static, gradient and RF
electromagnetic fields can severely distort the ECG, making observation of the morphologic
changes and detection of arrhythmia quite difficult. Monitoring using a different ECG lead view (I,
II, III, AVL, AVR, AVF) will minimize some of these artifacts.
wECG Module and ECG Lead Cable
The wECG module and lead cable are intended for patient uses when continuous ECG monitoring
or cardiac gating are required. The wECG module and lead cable may be used in the MR system
bore, although the module must not be placed within 28 cm (11 inches) of the MRI field of view
(FOV). For wECG module details, see page 2‐9. The components of the ECG lead cable are detailed
Refer to your facility's biohazard procedure for disposal of ECG lead cables when they become
unusable. Usually cables are disposed of as medical waste per facility procedures.
5‐2 Monitoring ECG Expression MR400 Instructions for Use
ECG lead cable label identifier
Velcro storage strap
Cable trunk with foam insulator
Lead cable clips
If dropped, the wECG module must be verified for correct operation before use; see page
Guard against the accidental ingress of liquid into the module, as measurements made by the
device can be adversely affected.