AT HEART RHYTHM 2016
SAN FRANCISCO (FRONTLINE MEDICAL NEWS) – Focal impulse and rotor modulation-guided ablation for persistent atrial fibrillation – either alone or in conjunction with other procedures – increased procedural times without improving outcomes, according to the first randomized trial to assess its utility.
In fact, enrollment in the rotor ablation-only (RA) arm was halted early for futility. “There was 100% recurrence” of atrial fibrillation (AF), said senior investigator Dr. Andrea Natale, executive medical director of the Texas Cardiac Arrhythmia Institute, Austin.
“I’m surprised it took this long for a randomized study, because this system has been around for 5 or 6 years,” noted Dr. Natale . “Our community should demand these sorts of studies earlier, because it’s not fair for patients to go on with a procedure for years that has not been proven to be effective.
“For us, unless there is a new version of rotor mapping that I feel is significantly different, this will be the end of rotor ablation in my lab with this system [the Topera Physiologic Rotor Mapping Solution],” Dr. Natale said at the annual scientific sessions of the Heart Rhythm Society.
In the study , his team randomized 29 patients to RA only, 42 to RA plus pulmonary vein antral isolation (PVAI), and 42 to PVAI plus posterior wall and nonpulmonary vein trigger ablation.
At about 1 year, four RA-only patients (14%), 22 RA plus PVAI patients (52%), and 32 patients in the PVAI plus trigger group (76%) were free of AF and atrial tachycardias without antiarrhythmic drugs (P < .0001).
Meanwhile, RA alone and RA plus PVAI cases took about 230 minutes, while the more effective PVAI plus trigger approach took about 130 minutes (P < .001).
There was “a very poor outcome with rotor-only ablation,” Dr. Natale said. “There isn’t a benefit either alone or as an add-on strategy, at least with this mapping software.”
Perhaps “people who think rotors don’t exist are right,” he added. On the other hand, maybe the basket mapping catheter doesn’t touch enough of the left atrium, or the software that makes sense of what the catheter detects needs to be improved, Dr. Natale noted.
All the patients were undergoing their first ablation. They were in their early 60s, on average, and most were men. The mean left atrium diameter was about 47 mm, and mean left ventricle ejection fraction about 55%. There were no statistically significant differences between the study arms, and no significant differences in outcomes between the 70% of patients with persistent AF and the 30% with long-standing persistent AF.
There was no industry funding for the work. Dr. Natale disclosed relationships with Biosense Webster, Boston Scientific, Janssen, Medtronic, and St. Jude Medical.
