The use of Cardiac Implantable Electronic Devices (CIEDs) has increased dramatically, due in part to expanded indications for their use and the aging of society. An estimated 75 per cent of patients who currently have an implantable cardiac electronic device will need magnetic resonance imaging (MRI) during their lifetimes; it is estimated that volume of pacemakers will reach more than 1.4 million units by 2023.
In the past, MRI was contraindicated in all patients with implantable cardiac devices because of concerns that the powerful magnetic and radiofrequency fields generated during imaging might damage device components, inhibit pacemaker function, trigger rapid pacing and deliver inappropriate shocks.
In Affidea Sligo, in conjunction with Sligo University Hospital and the HSE, our team has to date safely performed MRI examinations on 5 patients in the North West with CIEDs, including:
- MR conditional pacemakers
- MR conditional ICDs (Implantable Cardioverter Defibrillators)
- MR conditional Loop Recorders
Our local team of Radiographers, Radiologists and Cardiac Physiologists have designed a policy in conjunction with the manufacturer guidelines to safely perform MRI examinations. Our policy outlines the steps from assessing device system conditionality, to device programming pre- and post- scan, and safe monitoring of the patient during the scan. The overall thrust of the policy is to ensure the safety of the patient who is implanted with such a device undergoing an MRI scan.
Image A: Gradient echo transverse MRI image showing an MR Conditional Cardiac Pacemaker insitu
Image B: Chest X-Ray showing position of Cardiac Pacemaker
Procedure in a nutshell:
- Clinical Specialist in MRI checks the conditionality of the device; recent Chest X-ray, make and model of CIED.
- Cardiac Physiologist interrogates the MR conditional device and switches to “safe scan” mode.
- The Radiographer safely performs the MRI examination in low SAR mode, while the Cardiac Physiologist continuously monitors the patient’s ECG, BP and O2 saturations.
- Immediately after the MRI scan, the Cardiac Physiologist programmes device out of “safe scan” mode to restore to normal pre-scan settings.
- Continuing to make a difference to the lives of our patients in the North West.
- To accommodate MRI scans locally for patients with pacemakers.
- With an ageing population, pacemakers will be more commonplace; Affidea Sligo and the HSE are ensuring the needs of these patients are continually met.