"Hi, I'm Vivek Reddy from the Mount Sinai Fuster Heart Hospital in New York City, and I'm the principal investigator for the ADVENT LTO trial.

Tell us about the ADVENT LTO results – is 'fast' PFA just creating temporary stunning instead of permanent transmural lesions?

ADVENT was the first — and at this point still only — randomized trial that compared pulsed field energy to thermal energy in patients with paroxysmal atrial fibrillation. We published that a few years ago. What it showed was that with one year follow-up, patients who underwent pulsed field ablation with the pentaspline catheter had equivalent outcomes to patients who underwent ablation with either radiofrequency or cryoablation. It was a well-received trial, but it left some open questions.
The first was: what happens long term? Will the effect remain or dissipate over time? The second concerned disease progression — specifically, whether the rate of progression from paroxysmal to persistent atrial fibrillation differed between the radiofrequency and cryo arms. These open questions prompted us to conduct the ADVENT LTO trial.

ADVENT LTO is a long-term follow-up study to the original ADVENT trial. We returned to the original centers, reconsented patients, provided Holter monitors to assess rhythm outcomes, and reviewed healthcare utilization data — including cardioversions, antiarrhythmic drug use, and repeat ablation requirements. We enrolled approximately 63% of the original ADVENT cohort, giving us around 360 patients relatively evenly split between pulsed field and thermal ablation arms.
What we found was that the success seen with pulsed field remained non-inferior to radiofrequency and cryoablation over approximately four years of follow-up. In fact, pulsed field was around 9 percentage points higher in success rate than thermal ablation on an absolute basis — though this did not reach statistical significance. A landmark analysis also showed that if a patient had no recurrence at the end of year one, their probability of recurrence over the subsequent three years was only around 9% in aggregate. From a safety perspective, no new unexpected safety events emerged. On disease progression, both groups showed very little movement from paroxysmal to persistent atrial fibrillation — if anything, the pulsed field group was numerically less likely to progress.

How does this translate to patient outcomes?

When considering patient outcomes, we can look at either quality of life or healthcare utilization. From a quality of life perspective, both the radiofrequency and pulsed field groups showed significant improvement compared to baseline — before the ablation procedure — with no meaningful difference between groups.
On healthcare utilization, there was numerically less utilization in the pulsed field group compared to thermal ablation. Looking at individual components, pulsed field patients were statistically significantly less likely to require antiarrhythmic drug use or to undergo repeat ablation — both meaningful outcomes for patients managing a chronic condition like atrial fibrillation.

Is this data enough for us to change practice – what are your recommendations?

Many centers have already transitioned to pulsed field ablation, and I think these findings should make them feel very comfortable that there is no long-term concern for their patients. For physicians who have been waiting to see long-term data before making the switch, I believe ADVENT LTO provides the confidence they need — that they can expect the same, and potentially even better, long-term outcomes than they are currently achieving with thermal ablation.”