By Laura Freeman

“Year ago, when Radiofrequency Ablation Therapy (RF) was introduced, it was a major advance over trying to manage atrial fibrillation with only medications and the few other treatments we had,” UAB Chief of Cardiac Electrophysiology Tom McElderry, MD said. “However, it wasn’t perfect. Targeting the right tissue took skill, and there was always a risk of serious damage to the esophagus and nerves. Today, there is still a place for RF and other thermal tech in some applications, but now that the pulse field option is broadly available, I think it will become the treatment of choice in most cases.

“Around a decade ago, I began looking into alternatives to thermal energy ablation and became interested in research using pulse field technology. The big advantage was that it could be tuned to specifically target heart muscle tissue without risk to the esophagus and other tissue.”

In addition to participating in research as the pulse field technology was being developed, once it was ready to go into clinical trials, McElderry performed the first procedure using the technology in in a human patient in Paraguay.

“As researchers studied atrial fibrillation and more was known about how it occurs, we saw that the electrical impulses that cause fibrillation often arise around the pulmonary vein and are conducted along it to the heart,” he said. “A key strategy in pulse field ablation is to isolate the area so there is no longer a pathway for impulses to travel. It’s a bit like the insulation around a power cord that lets you use it without getting shocked.”

Instead of the thermal energy used in RF ablation, pulse field technology uses a series of high powered, short duration electrical pulses specifically tuned to disrupt the cells along the pulmonary vein.

“The targeted cells burst and empty into the surrounding area, which kills adjoining cells and starts to form an insulating barrier that will help to block fibrillation impulses,” McElderry said. Like thermal ablation, pulse field equipment works through a catheter. However, the system allows us to work faster than with RF. Procedures are usually same day and patients are ready to go home in the evening or before. Best of all, we don’t have to worry about an esophageal fistula or ulcer, or phrenic nerve injuries. In Europe, some procedures are done with conscious sedation, which allows patients to recover even faster. They can leave the hospital sooner, have something to eat and go home to rest and recover.”

The underlying causes of atrial fibrillation can be related to genetics, aging, hypertension, sleep apnea, obesity and other factors. What may start as a mild symptom can quickly become serious, interfering with the heart’s pumping ability and encouraging the development of clots that can travel to the brain and cause a stroke, or move into the lungs and heart.

“Patients recently diagnosed with atrial fib are usually prescribed blood thinners to reduce the risk of clots. Testing usually follows and may include a halter monitor to determine the frequency and intensity of symptoms. As symptoms become worse, ablation becomes a consideration to discuss with the patient,” McElderry said.

Follow-up studies have shown that the effectiveness of the new option in both paroxysmal and persistent atrial fibrillation is comparable to thermal ablations when patients are checked 90 days post procedure after their bodies have had time to settle into what will be their normal rhythms.

The pulse field option has been released relatively recently, but it is generally available in most areas and more cardiac electrophysiologists are being trained to use the new technology. Equipment used in performing the procedure is available from two different companies. As of now, costs for ablations done using the new option are slightly higher than those using older technologies, but there are also advantages in efficiency and safety. Insurance coverage should be reviewed and approved prior to the procedure.

“In some cases with other complexities to consider or unusual trigger areas, it’s possible that RF ablation may still have a role. However, the advantages of pulse field ablation are clear, offering an equivalent likelihood of successfully relieving symptoms without the risk of complications from a thermal injury to other tissues,” McElderry said.