The Single Shot Champion trial compared pulsed field ablation (PFA) and cryoballoon ablation in paroxysmal atrial fibrillation, showing comparable safety and efficacy. While PFA had fewer recurrences and shorter procedures, the trial’s key innovation was continuous monitoring via implantable loop recorders, highlighting AF burden as a more relevant outcome measure than recurrence alone, signaling a paradigm shift in rhythm management.

When it comes to rhythm control in atrial fibrillation (AF), success has often been defined by what we see (or fail to see) on a 12-lead ECG or 24-hour Holter. But as technology advances, so does our ability to measure, monitor, and define what really matters: AF burden over time. 
A Trial with Continuous Eyes on the Rhythm
The Single Shot Champion study is the first randomized controlled trial comparing pulsed field ablation (PFA) and cryoballoon ablation in paroxysmal AF patients, using ICMs for 12 months of follow-up.
In this non-inferiority trial, PFA matched cryoballoon in safety and efficacy. Notably, while fewer arrhythmic recurrences (37% vs. 51%) and shorter procedures (55 vs. 73 minutes) were seen with PFA, the trial was not powered to prove superiority.
But what truly sets this trial apart is not the technology used for ablation, but the one used for follow-up. Continuous rhythm monitoring allowed to measure not only recurrence, but AF burden.
A Paradigm Shift in How We Define Success
The use of ICMs in this study reinforces the idea that AF burden, not just recurrence, may be a more meaningful and actionable metric. This approach reflects a shift endorsed by the ESC Council on Stroke and EHRA, who advocate for standardized AF burden metrics to guide therapy and improve study comparability.
Looking Ahead
The Single Shot Champion study underscores a pivotal moment in AF ablation: not just a technological advance, but a conceptual one. With continuous monitoring and patient-centered metrics like AF burden, we are finally beginning to align what we measure with what matters.