乌鸦传媒

SAN FRANCISCO -- Targeting electrical "rotors" in the heart during ablation actually impaired the success of radiofrequency ablation for persistent or long-standing persistent atrial fibrillation (Afib), the OASIS trial showed.

Instead, the most successful strategy among the three compared head-to-head was a conventional pulmonary vein isolation (PVI) plus non-pulmonary vein trigger ablation without any rotor-guided ablation (P<0.001 versus rotor ablation alone and P=0.02 versus the combination).

For the primary endpoint of freedom from atrial fibrillation or tachycardia without antiarrhythmic drugs at 12 months,, of the Texas Cardiac Arrhythmia Institute in Austin, and colleagues reported rates of:

• 14% (4 of 29) with focal impulse and rotor modulation (FIRM)-guided ablation only, without pulmonary vein isolation
• 52.4% with FIRM-guided ablation plus pulmonary vein isolation
• 76% with pulmonary vein isolation plus non-pulmonary vein trigger ablation

Instead of adding to procedural success, the rotor mapping and ablation just added to the duration of the procedure for a mean 131 minutes vs 222 rotor-only ablation and 233 combined (both P<0.001), Natale reported here at the Heart Rhythm Society meeting and simultaneously online in the Journal of the American College of Cardiology.

"Our findings are not off the charts," as they are in line with what other groups have reported in prior, albeit nonrandomized, comparison data excluding patients on-drug, Natale said at the late-breaking clinical trial session.

It's possible that the explanation for the lack of benefit was that the software for identifying rotors wasn't effective; that the mapping catheter doesn't cover sufficient surface to catch all relevant rotors; or simply that rotors don't really exist or don't matter.

"I don't think it's the end of this technology, but certainly it is a study that does raise some question about the validity of this approach," he said. However, he added that "unless there is a new version of rotor mapping that is significantly different, in my lab this will be the end of rotor ablation with this system."

"Atrial fibrillation ablation is a work in progress," , of Piedmont Hospital in Atlanta, said at a press conference he co-chaired discussing the late-breaking trials. "Especially in persistent [Afib] patients, it's still problematic. Our success rates are less than we would like. We still have a lot of work ahead of us. I think it's going to take quite awhile to get there."

The OASIS trial is the first head-to-head comparison, despite the rotor technology being around for several years, which Natale suggested was unacceptable.

"Our community should push, should demand, this kind of result [from a randomized trial] early on because after all it's not fair for the patients," he said, calling for no further consecutive series to be done.

Comment