In AF Treatment in a DecadePulsed Field Ablation: The Most Significant Advance

Why this technology matters — and why I believe it represents a step change

I have been performing AF ablation for over fifteen years. In that time I have witnessed significant advances: the refinement of three-dimensional mapping systems, the development of contact force-sensing catheters, the widespread adoption of cryoballoon ablation. Each has improved the reliability and efficiency of pulmonary vein isolation. But pulsed field ablation — PFA — is different in kind, not just in degree. It represents the first genuinely new energy modality in catheter ablation since cryoablation, and the clinical evidence supporting it is compelling.
We now offer PFA at OneWelbeck Heart Health as part of our advanced AF ablation programme.

What is Pulsed Field Ablation?

Traditional ablation uses either radiofrequency (RF) energy — essentially heat — or cryoablation — extreme cold — to create scar tissue that electrically isolates the pulmonary veins. Both approaches are effective, but they are thermally non-selective: they damage whatever biological tissue they contact, including occasionally the oesophagus, the phrenic nerve, or the pulmonary vein wall itself.
PFA uses a fundamentally different mechanism. It delivers a series of ultra-short, precisely calibrated electrical pulses that create a phenomenon called irreversible electroporation in targeted cells. The key innovation is selectivity: cardiac muscle cells are far more susceptible to electroporation than the surrounding connective tissue, smooth muscle, and neural structures. This means that PFA can achieve reliable and durable pulmonary vein isolation while substantially reducing the risk of collateral damage to adjacent structures.

What Does the Evidence Show?

The ADVENT trial, published in the New England Journal of Medicine in 2023, was the pivotal prospective randomised study. It compared PFA with conventional thermal ablation (radiofrequency or cryoablation) in over 600 patients with paroxysmal or persistent AF. The primary efficacy endpoint — freedom from recurrent AF at 12 months — was non-inferior in the PFA group compared with thermal ablation. The safety profile was strikingly favourable: there were no cases of oesophageal fistula in the PFA arm, which is one of the most feared and potentially fatal complications of conventional RF ablation. There were also no cases of pulmonary vein stenosis.
The PULSE-AF trial extended these findings to persistent AF, again demonstrating non-inferior efficacy and a highly favourable safety profile.

Who Benefits Most from PFA?

PFA is an appropriate first-choice option for most patients undergoing catheter ablation for AF. It is particularly valuable for:
•Patients undergoing their first AF ablation, where the safety profile of PFA offers advantages over thermal techniques
•Centres performing high volumes of AF ablation, where the procedural efficiency of PFA (often shorter procedure times than RF ablation) is clinically meaningful
For more complex cases — including patients with long-standing persistent AF or significant atrial fibrosis on cardiac MRI — PFA is being developed to address not just the pulmonary veins but also posterior wall isolation and additional substrate ablation. This is an area of active evolution.

A Note on the Technology Landscape at OneWelbeck

At OneWelbeck Heart Health, AF ablation is performed using PFA technology ultrasound-guided transseptal access and transoesophageal echocardiography. The combination of real-time imaging, and PFA energy delivery represents, in my view, the current safest standards for AF ablation whilst providing excellent real-world outcomes. We also utilize 3D mapping technology CARTO for complex mapping (Johnson and Johnson) for complex cases, including repeat AF ablations, and complex atrial flutters and supraventricular tachycardia (SVT).
Our recently published data (Kanthasamy, Finlay, Lim et al., Heart Rhythm 2025) across 450 consecutive patients performed in our day-case ambulatory setting confirms that this approach can be delivered safely and effectively outside the traditional hospital environment — with complication rates comparable to major hospital-based series and high patient satisfaction.

To discuss a comprehensive AF management plan, including lifestyle optimisation, book a consultation — drboonlim.co.uk or call 0208 187 9888