The MRI scanner is a tube surrounded by a giant circular magnet which creates a strong magnetic field. This magnetic field may affect any metal parts or devices in your body – including:
- pacemakers and their wires
- implantable cardioverter defibrillators (ICDs)
- metal heart valves
- brain aneurysm clips
- artificial joints
- dental fillings
How can the MRI harm the patient with pacemaker or other device?
Whether you can get an MRI, depends on what type of device you have. Always tell medical staff beforehand, because:
- MRI can affect the settings of your device, as each one is programmed specifically for your heart. Malfunction of the device may lead to heart arrhytmia.
- During the MRI examination, an alternating magnetic field is created. If you place a wire or metal device within alternating magnetic field, it could generate electric current and heat up. For pacemakers and defibrillators, metal leads are implanted in the body and the heart muscle. These leads that come within the MRI scanner’s alternating magnetic field can heat up while being in contact with your heart. This can possibly cause burns of heart muscle. Burns will turn into a scar tissue as a depreciated replacement of healthy cardiac muscle cells.
It’s important and helpful to know the type of your device. It gives your doctor all the important information he needs on whether it is possible and safe to perform an MRI scan.
When you get an implanted device such as a pacemaker or defibrillator, you receive a card identifying that device with all useful information.
What are the opportunities for a patient with pacemaker?
The alternative to MRI is to have a CT scan instead. CT uses radiation and will not affect your pacemaker. The only problem may be a lower quality of the images. Metal on CT scan creates dense streaks that can partially obscure the images. However, if you have any metal device implanted in your body, it will be safe for you to have a CT scan.
Most heart valves and coronary artery stents currently on the market can go safely through an MRI scanner. Manufacturers have developed also some pacemakers and defibrillators that can be scanned with an MRI. However, it is always important to inform your specialist and check properly, whether is your device suited for MRI examination too.