MRI-Safe Pacemakers On the Way

This week Medtronic will begin shipping to hospitals in the United States the first pacemaker approved by the FDA as safe for most MRI scans. For consumers, it is a significant step in what is expected to be a wave of new MRI-compatible implanted cardiac devices.

With some rare exceptions, there are few drawbacks to having a pacemaker. But you need to avoid powerful magnets. No problem being around your microwave or computer and when you talk on a cell phone, just hold it on the opposite side of your body from the pacemaker. But it’s best not to walk through airport security scanners, and instead submit to a body search and hand-held scanner. The biggest "no" that accompanied your pacemaker is to avoid any magnetic resonance imaging (MRI) exam. That may not have seemed like a problem at the time you agreed to get a pacemaker implanted. But we never know what turn our health may take. And there are many conditions for which doctors seek to learn more through an MRI scan that uses a very strong magnet, radio frequencies and a computer to produce images of soft tissue, bone, and blood vessels. Because it produces such detailed images of soft tissue, it is frequently used for organs of the body such as liver, bowel, pancreas, kidneys, brain and spinal cord. The MRI, which does not require ionizing radiation, is also used in diagnosing and staging cancers and pinpointing heart problems.

But, only a few medical centers in the United States and maybe 10 worldwide have the ability to perform MRIs on patients with the pacemakers now in use. Most people wearing pacemakers who need an MRI have been unable to get one. So getting a pacemaker that is safe to use during an MRI is a big deal for heart patients.

However, this Medtronic first-generation Revo MRI SureScan Pacing System has some significant limitations.

1. The MRI-pacemaker is for new heart patients. Patients who already have a pacemaker can not get this new model unless they undergo the risky procedure of having their old pacemaker completely removed.

2. Patients must have the Revo pacemaker implanted for 6 weeks before receiving an MRI.

3. The Revo pacemaker requires a certain position of the patient inside the MRI tube so as to avoid most chest scans.

4. And Owen Faris, senior scientific reviewer for the FDA, explains that the new pacemaker won’t work for all types of MRI scans and won’t work in all MRI scanners.

5. Medicare does not now pay for MRI scans on a patient who has a pacemaker, but Wendy Dougherty, spokesperson for Medtronic, says that Medicare will pay for MRI scans done on a patient wearing the new Revo pacemaker. Sources I talked to were not sure if this would happen quickly.