In the past decade, the use of MRI scanners has skyrocketed. Because the machines are able to provide relatively detailed images of soft tissues, they are extremely valuable in diagnosing cancers, heart problems and even back pain. These machines use a powerful magnetic field, radio frequency pulses and a computer to produce pictures of internal body structures.
But MRIs have been off limits to patients with implanted heart pacemakers. That's because the MRI's magnetic field could wreak havoc on a pacemaker's electronic circuitry. Or worse, some of the pacemaker's metal components could heat up and literally cook parts of the heart.
But Medtronic of Canada Ltd. has obtained Health Canada's approval to sell a new pacemaker that is compatible with MRIs. The device, more than a decade in the making, contains new circuitry and components that are resistant to the magnetic fields.
"This is a major technological breakthrough," said Anne Gillis, a professor of medicine at the University of Calgary who was involved in the clinical trials.
The new pacemaker will likely cost several hundred dollars more than earlier models, which range in price from $2,000 to $5,000.
Other medical-equipment makers are also planning to introduce similar pacemakers.
Dr. Gillis expects most Canadian hospitals will eventually choose to implant MRI-compatible pacemakers in their patients.
But the new models won't be an option for the 120,000 Canadians who are already equipped with a pacemaker. The replacement operation would subject the patient to unnecessary risk, Dr. Gillis said.