Disclaimer: This program is for educational purposes only and reflects independent editorial commentary. It is not medical advice and should not replace clinical judgment or review of primary sources and guidelines. The views expressed are those of the host and contributors.
Niraj Sharma: Welcome to EP Edge Journal Watch. I'm Doctor. Sharma and thank you for joining me for this special edition. Today we are focusing on the new EHR A Scientific Statement on Pulsed Field Ablation for atrial fibrillation. I have to say at the outset, this is a very thoughtful document.
It is broader than the prior HRS statement, more detailed in its science and more practical in how it approaches real world workflow. What I appreciate most is that this statement does not treat PFA like magic. It does not fall into the shortcut of calling PFA simply non thermal and moving on. Instead, it repeatedly emphasizes that PFA is heterogeneous, platform specific, and still evolving. That is exactly the right tone for where the field is today.
My goal in this episode is not just to summarize the statement, but to walk through it section by section, explain what it gets right, where it is less convincing, what the supporting studies actually mean and how we can use this in practice. At the highest level, this is probably the most complete AF specific PFA review we have right now. It is strongest when it talks about pulmonary vein isolation in contemporary atrial fibrillation programs. It becomes progressively less secure when it moves beyond pulmonary vein isolation into persistent atrial fibrillation substrate modification, non pulmonary vein targets, linear lesions, appendage isolation, ventricular work, and broad first line enthusiasm. So as we go through this, keep one framework in mind trust the document most where the evidence is mature.
Be more skeptical where the field is still trying to catch up with its own enthusiasm. Let s start with the introduction and the overall framing. This opening section is strong. It correctly positions PFA as the next major energy shift after radiofrequency and cryoballoon ablation. And that is fair.
The clinical problem has always been the same. Can we achieve durable pulmonary vein isolation while reducing collateral injury? The statement makes the case that electroporation rose so quickly because it appeared to offer exactly that combination, and the evidence supporting that enthusiasm largely comes from the pulmonary vein isolation space. Now here is where caution The introductory tone is understandably optimistic, but it can make the arc of clinical adoption sound more settled than it really is. Yes, modern PFA workflows have shown comparable efficacy and often shorter procedures, but that does not automatically mean that all strategic implications of PFA are solved across all device families, all operators, and all substrates.
That is an important distinction. When we say a new modality is effective for pulmonary vein isolation, that is not the same as saying it has solved durability everywhere, solved dosing everywhere, or solved safety everywhere. Those are very different claims. So the EP Edge take here is straightforward. The introduction is compelling and clinically relevant, but it should be read as the opening chapter of an atrial fibrillation pulmonary vein isolation statement, not as proof that PFA is already a universal ablation platform for everything we may want to do in the lab.
Next is the biophysics section and in many ways this is one of the best parts of the entire document. Why? Because the authors resist oversimplification. They remind us that PFA is not contact independent, it is not completely non thermal, and it is not somehow exempt from tissue and vascular biology. That matters because too much of the early PFA narrative treated it as if electric fields somehow bypassed the ordinary rules of lesion creation.
The statement appropriately discusses field strength gradients, reversible versus irreversible electroporation, endothelial effects, microvascular injury, and even thermal effects close to the electrode. It also explicitly acknowledges blood cell electroporation and hemolysis. That is important because hemolysis is not a theoretical footnote anymore. It has become one of the meaningful safety signals that real world operators need to respect. Now let me translate some of this into practical language.
When we say reversible electroporation, we mean the electric field perturbs the cell membrane but the cell survives. When we say irreversible electroporation, we mean the membrane injury is sufficient that the cell cannot recover. That is the lesion we are aiming for. But the exact threshold for that effect is not uniform across tissues, and it is not identical across platforms. That leads to one of the biggest limitations in the field.
We still do not have device agnostic thresholds that operators can apply across systems. We also do not have fully transparent public access to all waveform details across manufacturers. And that means that collective learning is still partly constrained by proprietary design. For clinicians, the practical takeaway is this: PFA is tissue selective but not tissue invulnerable. It is minimally thermal, not truly non thermal.
And it is contact sensitive, not contact free. From there, the statement moves into technological considerations. This section is useful because it refuses to lump every PFA platform together, and that is one of the most important messages in the entire paper. PFA is not a class effect. Catheter geometry matters, electrode arrangement matters, waveform design matters, vectoring matters, dosing strategy matters, irrigation matters, and how the system integrates with mapping and workflow also matters.
The section does a good job describing different architectures, including circumferential single shot systems, larger footprint mapping integrated systems, focal platforms, and dual energy approaches. That is valuable because it reminds the reader that two operators can both be doing PFA and actually be doing very different procedures in biologic and procedural terms. What is less satisfying is that the section is better at cataloging devices than at guiding decisions. In other words, it tells us what exists, but less clearly tells us what each platform is best suited for, where each system is more vulnerable, and what specific complications should make us more cautious. That is the kind of question clinicians actually ask: Which platform is more likely to run into hemolysis with high lesion burden?
Which setup is more likely to be problematic near sensitive coronary anatomy, which may be less convincing once you move beyond standard pulmonary vein isolation? So the EP Edge take is that this section is necessary, but incomplete in a practical sense. The next evolution of the field should move beyond platform description and toward platform stratification. Now to Patient Selection and Procedural Considerations. This is where the statement becomes especially relevant to everyday clinical practice.
To its credit, the document is strongest and most confident in de novo paroxysmal atrial fibrillation. It is more guarded in persistent atrial fibrillation and redo procedures. That hierarchy of confidence is appropriate. And frankly, it is probably one of the most responsible parts of the paper. The statement also acknowledges that pulmonary vein isolation only remains a reasonable strategy in selected persistent atrial fibrillation patients, while the role of additional lesion sets remains unsettled.
Again that is a realistic stance. Where I think the paper becomes a little too reassuring is in the line suggesting that there are no PFA specific contraindications beyond the usual contraindications to ablation. That may be technically defensible if you are speaking only about absolute contraindications, but clinically it misses the point. There are clearly PFA specific caution domains: high lesion burden, renal vulnerability, coronary proximity, metallic hardware interactions, extensive non pulmonary vein lesion plans, and anatomies that may require repeated energy delivery. In other words, even if we do not call these formal contraindications, they absolutely should change operator behavior.
That is what matters clinically. The document also could have gone further with subgroup structure. What about patients with very large atria, advanced atrial myopathy, chronic kidney disease or scar heavy redo substrate? These are the real world patients who stress test our assumptions. So in practice, use this section confidently for straightforward pulmonary vein isolation planning.
Use it more cautiously once you move into persistent atrial fibrillation substrate work, redo work, or device adjacent anatomy. The procedural workflow chapter is probably the most practically useful section in the whole document. It feels like it was written by people who actually live in the lab. The discussion covers anesthesia versus deep sedation, imaging strategy, fluoroscopy only workflows, electroanatomic mapping, transseptal issues, air embolism prevention, device interaction, vagal reactions, contact assessment, dosing, endpoints, and same day discharge. That is real procedural content, not abstract policy language.
But even here, there is an important tension. The paper sometimes places multiple workflows side by side in a way that can make them sound equally mature across all settings. They are not. A fluoroscopy only PFA case in a high volume experience center is not the same thing as exporting that workflow to a lower volume program early in its learning curve. The same goes for same day discharge, reduced imaging, or minimal post isolation testing.
Feasible does not mean universally reproducible. I think the biggest unresolved issue here is dose discipline. The statement appropriately notes that dosing strategies still rely heavily on manufacturer guidance and that evidence supporting those strategies remains limited. That is a bigger problem than it may sound, because in PFA efficiency can easily drift into overtreatment. If contact is suboptimal, if positioning is imperfect, or if the operator gets uneasy about durability, there is a temptation to simply repeat applications.
And that repetition may feel harmless in the moment, but it is not biologically free. This is also where the issue of acute endpoint minimalism comes in. The statement downplays waiting periods and adenosine challenge after PFA. That is understandable because the workflow often looks cleaner, but acute silence does not always equal durable irreversible lesion formation. Stunning is not the same as permanence.
So the practical EP Edge take is this: use this workflow chapter as a mature field manual for experienced atrial fibrillation programs. Do not read it as permission to simplify everything in every case. The less experience the operator or the center has, and the more complex the anatomy or lesion plan becomes, the more conservative the workflow should probably remain. Now we get to efficacy and safety, and this is where the supporting studies become especially important. The statement is balanced here That is a major strength.
It does not market safety. It actually discusses safety. The chapter incorporates randomized trials, pivotal studies, registry data, and specific adverse event signals. That is how this field should be interpreted, not by slogans but by layered evidence. Let's unpack that.
Randomized trials comparing PFA with thermal ablation are important because they test whether newer technology can perform at least as well as established therapy. When you hear a term like non inferiority in this setting, it means the new strategy was tested to show that it is not unacceptably worse than standard treatment by a predefined margin. That is not the same as saying it is dramatically superior. It means it cleared a clinically meaningful bar. That is an important statistical distinction because clinicians sometimes hear non inferiority and mentally translated into equivalence or superiority.
Those are different claims. Large registries are also valuable but for a different reason. They give us a sense of what happens outside highly selected trial populations. They are particularly helpful for uncommon complications and real world workflow patterns, but registry data are observational. That means they are excellent for signal detection and external validity, but less definitive for causal comparisons than randomized trials.
The statement deserves credit for explicitly addressing hemolysis, acute kidney injury, coronary vasospasm, conduction effects, and delayed serious events. That is exactly the right level of seriousness. One line that deserves especially careful interpretation is the reassuring absence of reported atrioesophageal fistula in very large procedural experience. That is clinically meaningful and genuinely reassuring, but it does not prove zero risk, and that is an important statistical concept. The absence of observed events in a dataset does not mathematically prove the event cannot occur.
It means the event has not yet been seen in that exposure set. The one month blanking period suggestion is another provocative point. Directionally, it may turn out to be right in selected workflows. But we should be careful not to export that idea indiscriminately into all settings, especially when monitoring intensity is variable or when the ablation extends beyond standard pulmonary vein isolation. So the EP Edge take here is this: PFA has clearly improved the safety conversation in atrial fibrillation ablation, but safer is not the same as solved, and it is definitely not the same as invulnerable.
The training and education section is shorter but I would argue it is one of the most important in the entire statement, because it addresses the cultural risk in the field. As technology becomes easier to deploy, there is always a temptation to assume the cognitive demands have also become easier. This statement correctly rejects that idea. PFAS should be embedded within electrophysiology expertise, not detached from it. That is exactly right.
Procedural simplification should not be confused with conceptual simplification. If anything, a new energy source with proprietary waveforms, heterogeneous catheter architectures, evolving complication patterns, and uncertain non pulmonary vein durability requires more sophisticated judgment, not less. Where the chapter could have gone further is in differentiating competency. There is no single learning curve for PFA. The learning curve for a single shot pulmonary vein isolation platform is not the same as the learning curve for focal systems, dual energy systems, appendage adjacent work, or ventricular applications.
That matters for fellowship training, privileging, case selection, and institutional rollout. A program may be entirely competent in routine pulmonary vein isolation and still be very early when it comes to focal non pulmonary vein lesion work. So the practical use of this section is not just educational, it is institutional. It supports the idea that PFA should be democratized responsibly but not trivialized. Next, future directions and emerging applications.
This is the section that will probably generate the most excitement and also the most overreach if it is read too casually. The statement reviews posterior wall isolation, superior vena cava isolation, mitral isthmus work, appendage isolation, scar homogenization, cavotricuspid, isthmus ablation, ventricular arrhythmias, and supraventricular tachycardias. In that sense, it gives the reader a real sense of where the field is trying to go, but breadth can create false symmetry. Just because multiple applications are described in the same chapter does not mean they are equally ready for routine practice. They are not.
The recurring issue is acute success without durable certainty. That is especially true for linear lesion work, appendage isolation, and several non pulmonary vein targets, and the biologic brake pedals remain coronary vasospasm, conduction system effects, and reconnection. So when clinicians hear early success in these spaces, the right response is curiosity, not complacency. The correct reading is not that PFA can now do everything. The correct reading is that PFA may expand safely over time, but every new target needs its own durability data and its own safety data.
So yes, this section is exciting. But it is exciting in the way an early pipeline is exciting, not in the way mature routine practice is exciting. Before closing, it is worth comparing this EHR statement with the HRS and EHR scientific statement many of us have already reviewed. At a high level, the two statements agree on the core trajectory of the field. Both position PFA as a mainstream energy source for atrial fibrillation ablation rather than an experimental niche tool.
Both are strongest in de novo atrial fibrillation pulmonary vein isolation, and both emphasize that PFA should not be treated as a class effect. They also agree on the central safety reality. Signals for esophageal and pulmonary vein injury appear improved, but newer risks such as hemolysis, acute kidney injury, coronary vasospasm, device interaction, and delayed serious events mean that PFA should be viewed as safer, not solved. Where they differ is less about scientific direction and more about editorial posture. The HRS statement is more recommendation driven, more vote based, and more prescriptive.
The EHR statement is broader, more nuanced, and more procedural in tone. It reads more like a field manual than a mandate. So let me close with the EP Edge bottom line. This EHR statement is not a cheerleading document and that is to its credit. It is a serious, modern, clinically useful review of how PFA is actually being practiced in atrial fibrillation ablation today.
Its greatest value is that it normalizes nuance. PFA has real safety advantages, real workflow advantages, real platform differences, and still very real unresolved problems. Now, a quick recap of the key supporting studies and evidence strands we touched on. Randomized comparisons showed that PFA has earned a legitimate place alongside established thermal strategies for pulmonary vein isolation, but those trial designs usually test whether it is acceptably effective, not whether it is universally superior. Large real world registries strengthen the safety and feasibility story, but also reminded us that uncommon complications such as hemolysis, acute kidney injury, and coronary spasm remain highly relevant in practice.
Durability and redo data are encouraging, but once we move beyond standard pulmonary vein isolation, the field still needs much stronger long term evidence. All references and graphics are available on the LinkedIn newsletter, EP Edge Journal Watch as well as on Substack at epedge.substack.com. Thank you again for listening. This is Doctor. Sharma for EP Edge Journal Watch.
Take care and bye for now.