RADAR: Persistent AF ablation guided by novel mapping system successful
SAN FRANCISCO — A novel mapping system to identify drivers of atrial fibrillation beyond the pulmonary vein was associated with successful AF ablation at 9 months, according to the RADAR study presented at the Heart Rhythm Society Annual Scientific Sessions.
For the first-in-human, investigational device exemption study, Vivek Y. Reddy, MD, director of cardiac arrhythmia services for The Mount Sinai Hospital and the Mount Sinai Health System and the Leona M. and Harry B. Helmsley Charitable Trust Professor of Medicine in Cardiac Electrophysiology at Icahn School of Medicine at Mount Sinai, and colleagues used the novel mapping system (Radar, AFTx) in conjunction with a conventional mapping system (NavX, Abbott) to identify driver domains in high resolution using conventional electrogram signal processing.
“One of the biggest unmet needs in electrophysiology is finding targets for ablation of persistent atrial fibrillation,” investigator Moussa Mansour, MD, FHRS, associate professor of medicine at Harvard Medical School and Jeremy Ruskin and Dan Starks Endowed Chair in Cardiology and director of the Atrial Fibrillation Program at Massachusetts General Hospital, told Cardiology Today. “Pulmonary vein isolation alone has not been giving the results we hoped to see in persistent atrial fibrillation. There is a belief in the field that ablation of persistent atrial fibrillation requires identification of additional targets.”
The researchers created high-density AF maps of the left atrium of 64 patients (mean age, 64 years; 73% men; mean duration of AF, 13 months); eight patients also had maps created of the right atrium. All patients stopped antiarrhythmic drugs within 8 weeks of the procedure.
The primary endpoint was freedom from AF at 12 months, including a 3-month blanking period.
Mean mapping time was 22 minutes and mean ablation time was 28 minutes, Reddy said during a presentation.
An average of three drivers per patient in the left atrium and two drivers in the right atrium were discovered, and there were no adverse events associated with the procedure, he said.
At the end of the study period, 83% of patients were free from AF and 72% were free from AF, atrial flutter or atrial tachycardia, according to the researchers.
“This is the first study that showed this kind of success rate for persistent atrial fibrillation,” Mansour said in an interview. “This was due to the methods used. The idea is relatively simple but was not available before because we did not have strong enough computers to generate these maps in a short time. The next step is to conduct a clinical study where this technique for ablation would be compared to conventional ablation, which is just pulmonary vein isolation.” – by Erik Swain
Reddy VY, et al. LBCT03-05. Presented at: Heart Rhythm Society Annual Scientific Sessions; May 8-11, 2019; San Francisco.
Disclosures: The study was funded by AFTx. Mansour and Reddy report they received institutional research grants from AFTx. Reddy also reports he has financial ties with Abbott Vascular, Biosense Webster, Biotronik, Boston Scientific, CardioFocus, Circa Scientific, Iowa Approach, Manual Surgical Sciences, Medtronic and Philips.