Boston Scientific's pulsed field ablation delivers safety, procedure time gains in head-to-head afib trial

Boston Scientific has put forward pivotal clinical data from a head-to-head trial showing its pulsed field ablation approach for treating an irregular heartbeat can operate on par with traditional ablation methods while having fewer complications.

For patients with intermittent atrial fibrillation, the company’s Farapulse system was shown to be non-inferior to standard-of-care therapies—including thermal and cryoablation catheters—after one year, offering about the same reduction in arrhythmias.

The results were presented as a late-breaking study at the annual meeting of the European Society of Cardiology in Amsterdam while being published simultaneously in the New England Journal of Medicine.

Picked up via a $295 million acquisition in 2021, Boston Scientific’s Farapulse system generates short bursts of electric fields that are tuned to disrupt certain types of cells more than others—compared to the more indiscriminate ablation that comes from delivering heat or cold energy. In this case, the system targets the contracting heart muscle cells that can fuel an irregular heartbeat, while sparing more-resistant nerve cells and other nearby tissues, such as the esophagus, from any damage.

In Boston Scientific’s ADVENT trial, 305 patients were randomized to undergo pulsed field ablation, while 302 received either conventional radiofrequency or cryoballoon ablation. 

One year after the one-time, minimally invasive procedures—and without taking any medications for the condition—73.3% of pulsed-field ablation patients saw no signs of atrial fibrillation, compared to 71.3% in the control arm.

In safety measurements, the Farapulse group reported about the same rate of serious device-related complications in the week following the procedure, at six cases versus four cases. Over the longer term, Farapulse saw significantly less post-ablation narrowing of the pulmonary veins after three months, at 0.9%, compared to 12% in the control.

At the same time, Farapulse procedures were completed much faster—allowing for reduced X-ray exposure—with an average of just under a half hour, compared to 50 minutes of operating time with thermal and cryoablation.

“These data underscore the superior procedural efficiency of this novel technology, and real-world use continues to yield strong safety and efficacy outcomes,” Kenneth Stein, Boston Scientific’s global chief medical officer, said in a statement

Now, the company aims to study the system in persistent afib through a U.S. clinical trial that began enrolling participants earlier this year. Farapulse previously received a CE mark in Europe in 2021. 

Ahead of FDA review, but to help meet demand in the European market, Boston Scientific has been gearing up to increase its Farapulse production by establishing a second manufacturing site for the system’s pulse generators in Minnesota, according to a late July report from Medical Design and Outsourcing. 

Earlier this year, potential rival Medtronic posted results from its own pulsed field ablation treatment at the American College of Cardiology’s annual scientific session in New Orleans. The PulseSelect system was studied in both paroxysmal and persistent afib, with 70% and 62% of treated patients, respectively, reporting freedom from arrhythmias after one year.