Patient with Pacemaker for MRI
A 68-year-old male with a non-MRI-conditional pacemaker (implanted 5 years ago) is scheduled for an MRI of the lumbar spine. The patient reports that he needs the MRI to evaluate severe back pain. The pacemaker model is not MRI-safe, but the patient's cardiologist is available for consultation. The MRI department has a protocol for patients with non-MRI-conditional devices, which includes reprogramming the device to asynchronous mode and monitoring with ECG and pulse oximetry.
1. What are the risks and benefits of performing the MRI in this patient, and what should the technologist do?
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Risks: The magnetic field can cause lead heating, device displacement, and reprogramming. The radiofrequency energy can induce currents leading to arrhythmias or lead tip heating. Benefits: MRI may provide diagnostic information not available otherwise. The technologist should not proceed without a thorough risk-benefit analysis by the radiologist and cardiologist. The device should be reprogrammed to asynchronous mode, and the patient monitored. The technologist must ensure the patient is informed and consent obtained. If the benefits outweigh risks, proceed with caution using lowest SAR and limited scan time.
2. What safety precautions should be implemented before and during the scan?
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Precautions: Verify device model and leads, consult cardiologist, reprogram pacemaker to asynchronous mode or disable tachycardia detection, attach ECG and pulse oximetry, have emergency equipment and personnel available, use lowest SAR, limit scan time, and monitor patient communication. After scan, reprogram device and check function. Document all steps.