Emerging pulsed field ablation systems had their moments in the spotlight at the annual meeting of the Heart Rhythm Society (HRS), being held in San Diego this weekend.
The therapy has made a major impact in the treatment of atrial fibrillation, the most common irregular heartbeat, with platforms from multiple major medtech companies receiving international approvals in the past year—including Medtronic, Boston Scientific and Johnson & Johnson.
Pitched as a safer alternative to traditional ablations that use thermal energy, pulsed field ablation relies on quick bursts of electric fields to permanently disrupt the membranes of cardiac muscle cells that can drive arrhythmias—where the use of directed heat or cold may cause unintended damage to nearby organs and tissues.
At the HRS meeting, Abbott presented 12-month data from a clinical study that backed the European approval of its Volt system, awarded last month. That trial included people with persistent afib lasting longer than a week, as well as those with paroxysmal, or intermittent, disease.
After one year, 58.1% of treated patients with persistent afib were free of atrial arrhythmia symptoms, as were 83.5% of those with paroxysmal afib. The company said zero patients showed serious complications including hemolysis, coronary artery spasm, pulmonary vein stenosis, acute kidney injury or phrenic nerve injury—though 2.7% of Volt patients reported side effects logged by the trial.
In addition, a separate sub-analysis showed no significant differences in safety or acute effectiveness in procedures performed under conscious or deep sedation, compared to those under general anesthesia.
“Our goal from the beginning with the Volt PFA System was to design a PFA system that would provide outstanding results in patients battling a range of atrial arrhythmias, and the latest data from the Volt CE Mark Study is confirmation that the system will truly impact patient care in a positive way,” Christopher Piorkowski, chief medical officer of Abbott's electrophysiology business, said in a statement.
At the same time, J&J delivered first-in-human results from an ongoing trial of its Omnypulse platform, featuring a large-tip catheter for focal pulsed field ablation.
The Omny-IRE study included 136 patients with paroxysmal afib, and demonstrated 100% success in isolating the pulmonary vein using only five minutes of fluoroscopy time during the procedure. About 84% of those isolations remained secure when they were mapped again after three months.
J&J received an FDA approval for its separate Varipulse system in November of last year, following green lights in Europe and Japan. Its initial U.S. rollout was paused in January following reports of four strokes among early patients; commercial efforts restarted in February, with the company recommending that clinicians avoid stacking repeated ablations in the same tissue.
The meeting also saw Boston Scientific present new 12-month data from its Farapulse system, with its upcoming Farawave and Farapoint catheters, in patients with persistent afib. Farawave is being studied in pulmonary vein isolation and posterior wall ablation, while the adjunctive Farapoint is aimed at the cavotricuspid isthmus to treat atrial flutter.
The trial, Advantage-AF, met its primary endpoints, with 73.4% of patients showing freedom from afib, flutter and atrial tachycardia. Additionally, 81% showed no afib recurrence—including no need for taking new anti-arrhythmic medications—and 96.4% of people treated with Farapoint had no recurrence of atrial flutter. Patients were also implanted with an insertable cardiac monitor.
Farapulse is currently approved by the FDA for paroxysmal afib; Boston Scientific said it expects new green lights in persistent afib as well as for its Farapoint catheter in the latter half of this year.
Meanwhile, Kardium presented 12-month data from a clinical trial of its novel Globe system. Its spherical catheter—three centimeters in diameter and studded with 122 gold electrodes—is designed to fit within the openings of the pulmonary veins and then isolate them from the atrium with a single shot, encircling ablation delivered from any angle.
The company’s single-arm study included 183 patients; 78% showed no symptoms of intermittent afib after one year. Procedures took a total of about 95 minutes on average, including about 25 minutes for the ablations.
The Globe system, using radiofrequency-powered thermal ablation, previously received a CE mark approval in Europe. The updated hybrid version of the device adds pulsed field capabilities, while incorporating heart-mapping technology. Kardium raised $104 million in venture capital funding in June of last year to help complete its development.
Newcomer Field Medical also showed off first-in-human findings of its platform aimed at treating ventricular tachycardia.
In patients with scar-related v-tach—acquired after undergoing surgery or suffering a heart attack, among other conditions—78% demonstrated freedom from symptoms following treatment with the focal FieldForce system, while two of the 22 treated patients saw worsening heart failure.
Field Medical recently posted a $40 million series A financing round to support two pilot studies, including one in afib, as well as preparation for a planned pivotal trial in v-tach. The company previously logged a $14 million seed round in September 2023.
Finally, the HRS, in a joint statement with the American College of Cardiology, endorsed the development of protocols that would allow patients to be discharged the same day after undergoing a cardiac ablation procedure—including people treated outside of the hospital at ambulatory surgery centers.
With afib increasing in prevalence across an aging population, same-day discharge strategies could help improve patient access and reduce the healthcare costs that come with overnight stays, they said—adding that data from the COVID-19 pandemic showed ablations could be safely performed in ASCs.
However, the two groups cautioned that successfully implementing such a protocol would require close coordination of care with patients and caregivers, and that it should be based upon a shared decision-making process between the patient and physician with a focus on safety and comfort.