FIRE and ICE: Analysis Strengthens Case for Cryoballoon Over RF Ablation in Paroxysmal AF

Patrice Wendling

June 10, 2016

NICE, FRANCE — Prespecified secondary analyses from the FIRE and ICE trial show significantly fewer rehospitalizations and repeat ablations for patients with paroxysmal atrial fibrillation (PAF) treated with cryoballoon ablation rather than the gold standard of radiofrequency ablation[1].

"I do believe that 5 years from now there will be no more point-to-point ablation to isolate the pulmonary veins; everything will be done with this balloon technology," lead author Dr Karl-Heinz Kuck (Asklepios Klinik St Georg, Hamburg, Germany) said to an audible gasp here at the European Heart Rhythm Association (EHRA) EUROPACE-CARDIOSTIM 2016 meeting.

Dr Jonathan Kalman (Royal Melbourne Hospital, Australia) told heartwire from Medscape, "It is a bold statement, but I would make the observation that the differences were small, that the curves diverged late, and a 50% relative reduction is a 3% absolute reduction in cardioversions."

He added, "Radiofrequency technology continues to evolve. So I think it remains to be seen, but there's no question that for people doing RF ablation that these data represent a challenge."

As reported this spring by heartwire , treatment with the cryoballoon (Arctic Front, Medtronic) ablation demonstrated noninferiority—but not superiority—compared with a radiofrequency catheter (ThermoCool, Biosense Webster) ablation for the primary efficacy end point of time to first recurrence of atrial fibrillation (AF) >30 s, atrial flutter, or atrial tachycardia, use of antiarrhythmic drugs, or reablation.

In the secondary analyses, patients treated with cryoballoon ablation compared with radiofrequency ablation had significantly fewer all-cause rehospitalizations (32.6% vs 41.5%: P=0.01) and cardiovascular rehospitalizations (23.8% vs 35.9%; P<0.01), including AF hospitalizations, Kuck reported during the late-breaking session.

There were 49 repeat ablations in 44 patients treated with cryoballoon ablation and 70 repeat ablations in 66 patients treated with radiofrequency ablation (11.8% vs 17.6%; P=0.03).

There were 13 direct-current cardioversions in 12 patients in the cryoballoon arm and 28 events in 24 patients in the radiofrequency ablation arm (3.2% vs 6.4%; P=0.04).

In a subgroup analysis of patients with a prior cardioversion at baseline, 20.9% treated with cryoballoon and 48.9% treated with radiofrequency ablation had a CV rehospitalization (P=0.05), Kuck reported.

Mental and physical quality of life, assessed at baseline and every 6 months after ablation, improved in both groups at 6 months and was maintained throughout 30 months of follow-up.

Session cochair Dr Helmut Puererfellner (Elisabethinen Hospital, Linz, Austria) told heartwire the preplanned secondary analyses are a "mind-changer" that will clearly spark debate.

"It simply shows that the lesions might hold longer, and this seems to lead to fewer events in the phase after ablation and in the first year and even longer, and this is something we have to discuss."

He added, "It does not give a definite answer whether cryo is better because the primary result still remains the primary result; that it was noninferior."

Both Kalman and Puererfellner said it remains to be determined which patients are best served by cryoballoon ablation and that most labs will likely offer both procedures.

Based on the primary initial results of FIRE and ICE, Puererfellner said they've introduced cryoballoon ablation in his lab and that he will use both techniques going forward, initially favoring cryoablation for patients with a normal set of veins.

During the discussion following presentation of the data, Kuck said if there was a bias in FIRE and ICE it was in favor of point-to-point radiofrequency ablation because it was performed by extremely well-trained individuals. "At this point in time, doing a multicenter radiofrequency-based trial, you can't do better than what was done."

Kuck told heartwire that while there are strict rules on who can perform balloon-based procedures in the US, the data are likely to push wider application of the technology elsewhere. "There will be people, interventionalists, who will start to do balloon-based ablation procedures. I do see this, and our regulation at this point in time doesn't prevent them from doing it."

This shift will require some sort of global training and demonstration of competence to ensure that complications can be addressed should they arise during the procedure.

Still, he added, "The PVI-balloon–based procedure is such a safe procedure that I do believe that a very experienced interventional guy that is well trained in an [electrophysiology] EP lab can do it."

While the abstract drew a strong round of applause, Kuck has recently been in a far less desirable spotlight. Earlier this week he withdrew his candidacy for president of the European Society of Cardiology following an out-of-court settlement in Germany last week, according to a statement by the ESC.

According to Die Welt , he was reportedly found guilty of treating patients he did not see and received a €100,000 fine and 1-year prison sentence that was suspended if he commits no further fraud.

Kuck, a former president of the European Heart Rhythm Association, also stepped down from the board of this ESC subspecialty association, "in order to protect the reputation of the ESC," the statement noted, adding, "We wish to thank him for more than a decade of loyal service and his many contributions."

Kuck's withdrawal leaves Dr Barbara Casadei (Oxford University Hospitals, UK) as the sole candidate for the ESC presidency, which will be determined July 4, 2016.

Medtronic funded the trial. Kuck reports consultant fees/honoraria from Biosense Webster, Edwards Lifesciences, and St Jude Medical and serving as a speaker for Medtronic. Puererfellner reported serving as a consultant and speaker for St Jude Medical, Biosense Webster, and Medtronic.

Follow Patrice Wendling on Twitter: @pwendl. For more from, follow us on Twitter and Facebook.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: