So my name is Tobias Reichlin. I'm from the Inselspital, Bern in Switzerland. And today I'm going to discuss the findings of our SINGLE SHOT CHAMPION trial that we presented at this EHRA conference and published in the New England Journal of Medicine.

What is the importance of this study?

Over the past four years, pulsed field ablation has significantly changed the field of electrophysiology. And the entry ticket of pulsed field ablation was that it's a safer technology because the technology and the lesions are confined to the heart, so no risk for atrioesophageal fistulas, PV stenosis and phrenic nerve injury. Then we learned that the procedures are faster, so that's what many people liked, but so far we did not know, does it also result in better outcomes compared to thermal ablation or will it be the same?

What was the study design and patient population?

Yes, so this was a study done in patients with paroxysmal atrial fibrillation scheduled to undergo pulmonary vein isolation. And the design was an investigator-initiated, randomized, non-inferiority trial. And patients were randomized to pulsed field ablation using the FARAPULSE pentaspline device or cryoballoon ablation using the Medtronic Arctic Front Cryoballoon.

And in order to have a perfect assessment of follow up in all patients at the end of the ablation, implantable cardiac monitor was put in to have continuous rhythm monitoring during the study period. And the primary endpoint was the first recurrence of any type of atrial arrhythmia lasting more than 30 seconds using a blanking period of 90 days.

What were the key findings?

So I think the key findings were that recurrence of atrial fibrillation or freedom from recurrence of atrial fibrillation occurred in 62.9% of the patients in the pulsed field ablation group and in 49% of the patients in the cryoballoon group. And so that was a difference of 13.6% between the two modalities. And so the criteria for non-inferiority were met clearly. And subsequent superiority testing also indicated that the criteria for superiority were met, albeit with a just borderline p-value of 0.046.

So in a nutshell, I think this is now a study that is nailing for sure that PFA is non-inferior to cryoballoon ablation. But I think there's also a very, very strong signal that indeed pulse field ablation using this device is probably superior to cryoballoon ablation. And I think that's a very, very important message.

Based on these findings, how do you anticipate the adoption of pulsed field ablation will evolve in clinical practice?

So I think what we've seen over the past four years, but maybe more significantly over the past one and a half years, since the device is not only available in Europe but also in the US, is that a vast part of the field has already shifted to pulsed field ablation over those periods.

I think the results that we have presented in our trial do not provide many strong arguments that people should go back to cryoballoon ablation. And I think that the adoption of pulse field ablation will be even stronger in the months and years to come.

How might these results influence guidelines?

So I think these results on its own, it's a very strong signal that also outcomes are better. But given that the sample size was modest and the trial was not powered for superiority, I think it's important to now confirm that in larger outcome trials. And I'm quite optimistic that those also will show that indeed pulsed field ablation is superior to thermal energies in terms of clinical outcomes.

And then if that is true, I think then that will affect the guidelines in a way that first catheter ablations for paroxysmal atrial fibrillation should be done with pulsed field ablation. But it's a slightly way to go until then.

What are the next research questions that should be addressed regarding PFA?

In addition to these larger confirmatory trials in paroxysmal atrial fibrillation, I think the field of patients with persistent atrial fibrillation is where we struggle more. We know that pulmonary vein isolation might not be sufficient for all the patients, but we don't know what additional strategies might improve outcomes there.

And I think with the new tools that we have with this device and other PFA devices, that provides us now with an opportunity to repeat randomized controlled trials with strategies that have failed to show benefit with radiofrequency ablation, but now maybe can be redone and potentially could show benefit with pulsed field ablation.