For patients with heart rhythm disorders, such as atrial fibrillation, cardiac ablations can eliminate the problem at the source. These common procedures use heat or cold to destroy the cells generating irregular heartbeats. But the trick is identifying aberrant cells.
Now, Medtronic has introduced the CardioInsight, a high-tech vest that, when combined with CT imagery, provides detailed 3-D maps to locate problematic heart cells. The device received 510(k) approval from the Food and Drug Administration last week. Cardiac mapping has been around for a while, but Medtronic’s technology makes it noninvasive.
“The vest has around 250 electrodes on it,” said David Steinhaus, medical director of Medtronic’s Cardiac Rhythm and Heart Failure division in a phone interview. “It’s like taking an EKG from 250 different places around the chest. Once you’ve done that, you take a CT scan. Now you know where the heart is in space in relationship to the electrodes and the computer does the magic of putting it all together.”
Locating an arrhythmia’s birthplace can help electrophysiologists access the heart, target misbehaving cells and avoid healthy tissue. Cardiac mapping has been an important tool to make ablations safe and effective, but it has required catheterization.
“With the current technology, we need vascular access by a vein or artery to get to the heart, and the inside of the heart, and touch the heart tissue to make these maps from the inside,” said Jonathan Hsu, cardiac electrophysiologist and assistant clinical professor at UC San Diego in a phone interview. Hsu did not take part in the vest’s development. “The CardioInsight system hopes to do that noninvasively.”
In addition to potentially eliminating a cath procedure, the vest may also give electrophysiologists additional flexibility. The rhythm study may show a patient does not need an ablation or that the procedure might not help their condition. In other cases, the ability to observe a patient’s heart rhythm over extended periods could pay dividends.
“You must have the arrhythmia at the time you’re mapping,” said Steinhaus. “If a patient has a transient arrhythmia, you won’t see it because you only get a small period of time in the (electrophysiology) lab. A patient could put the vest on in the morning and keep it on the whole day.”
Medtronic has been working on the CardioInsight for many years. To some degree, they had to wait for processing power to catch up with the application.
“You are taking all these EKGs from different vantage points, and you’re projecting them back on the surface of the heart,” said Steinhaus. “You can imagine the kind of computing power it takes to do that.”
Steinhaus notes that the device will be competitively priced with other systems. The vest has been tested in around 600 patients, and more research could drive acceptance.
“I would like to see larger studies that show its effects on patient outcomes,” said Hsu. “As practitioners, we never say no to additional information. It helps plan procedures and makes them more safe and effective. Because it’s non-invasive, I believe electrophysiologists will embrace this technology.”