Remote magnetic navigation adds precision to heart procedure

Wearing a headset and sitting in a glass-walled control room in front of a bank of monitors, Dr. Adam Berman looks more like a television director than an electophysiologist.


“Now you’re going to have to play with it a little bit to set up this shot,” he says to those inside the electrophysiology lab at Medical College of Georgia Hospital and Clinics who are bedside with the patient. But Berman is actually the one cauterizing tissue around the pulmonary arteries in the left atrium of the patient’s heart to help rid him of abnormal rhythms called atrial fibrillation. He is just using a computer mouse and a joystick to do it.

Called remote magnetic navigation, a type of robotic procedure, the system uses two large magnets on rotating arms on either side of the patient that create an external magnetic field that a computer can then use to precisely guide the magnetic tip of the catheter.

Berman, who is director of cardiac arrhythmia ablation services for the health system, can make minute movements inside the heart to get to exactly the right spot and then cauterize areas that are causing the dysfunction, something he used to do manually. The difference is this time he is sitting comfortably in a chair instead of standing over the patient with 30 pounds of lead on him to shield him from the radiation of the fluoroscope.

“This is a three-hour case wearing 30 pounds of lead” normally, he said. “Our specialty actually has a great deal of orthopedic problems, which can limit your career. I have friends who can no longer do the cases because of spine issues.”

He can still see the fluoroscope on screen but can also see the electrical patterns from various areas of the heart, an ultrasound as well as a 3-D image of the heart that shows him where the instruments are, accurate to within a millimeter.

“You need all of this data,” Berman said. “The beauty of this is that I can sit down and with one mouse I can control all of this stuff.”

He slowly traces a line around the opening of all four of the pulmonary veins in order to isolate them from the heart wall.

“They discharge electrically,” Berman said, and are thought to throw off the normal rhythm of the atrium to create atrial fibrillation. By isolating them, “they are still returning blood vigorously from the lungs but they are electrically inert,” he said.

There are some initial disadvantages to using the remote system. In the beginning, Berman said, it added about 45 minutes to the case. And for someone used to doing things by feel with the catheter in his hands, it takes an adjustment to rely solely on visual cues.

“There’s a steep learning curve,” Berman said. “What I tell people is it is kind of like learning how to tie your shoes, except you are learning how to tie them backward.”

But he believes the benefits are better precision and potentially better outcomes, which are typically about 70-75 percent cures.

“I think robotic systems such as this one are more accurate than your hands because it allows you to move in extremely small and precise motions,” he said.

The catheter tip can make movements as small as 1 degree and 1 millimeter at a time, said Ginny Cauley, clinical training manager for manufacturer Stereotaxis. It is also much softer – Berman refers to it as a “spaghetti noodle” – much less stiff than traditional catheter, which should lower the risk of accidental perforation, he said.

There is less need for fluoroscopy which lowers the exposure for workers and the patient, Berman said.

“It plummets for me,” he said. “And actually it plummets for the patient, too.”

Berman said he could be considered “kind of a director” because the cases are digitally recorded, which creates a “movie” that can be shared with the patients, other doctors and students.

“For teaching, as an academic institution, it is absolutely fabulous,” he said.