Niraj Sharma: Welcome back to EP Edge Journal Watch. I am Doctor. Sharma and today we are unpacking the newly released twenty twenty six HRS and EHR A scientific statement on pulsed field ablation for cardiac arrhythmias. If you do AF ablation or you are building an AF program, this statement matters because it is trying to do something powerful. It is trying to standardize how the world does PFA.
Now before we critique anything, credit where it's due. This is a high effort, unusually comprehensive document for an emerging technology. The writing committee, co chaired by Drs. Atul Verma and Melez Hosseini, had to synthesize a mountain of rapidly evolving data, and they did it in a way that is readable and practical. But any critique worth publishing has to examine the lens through which the statement is written.
And here is the first lens. This statement is positioned to standardize workflows worldwide, yet the committee is 11 members, mostly electrophysiologists based in North America and Europe with a single member from Australia. That matters because PFA adoption, anesthesia models, intracardiac echo access, and post market update pathways vary dramatically across the globe. Guidance written primarily through a Western high resource lens can be excellent, but it can also be incomplete when you try to operationalize it in the real world. And here is the second lens.
This document is built on a voting system among those 11 committee members. They transparently report the vote counts. For example, the headline claim that should be the preferred initial energy source for pulmonary vein isolation is supported by eight of 11 votes. So my question is simple, does eight of 11 votes define a near universal global standard especially when the evidence is still highly platform specific? That's the theme of today's episode.
We're going to bridge the gap between societal consensus and the hard biophysical realities you face in the lab. Let's start with how to read this statement the right way. Whenever you see the phrase we recommend or we suggest treat it as a two part sentence. Part one is the advice, part two is the strength of the consensus and the number of voters behind it. And the voters are explicitly listed.
Five from The US, two from Canada and one each from France, Slovenia, Germany and Australia. I actually like this transparency. It forces us to separate workflow guidance from guideline grade mandate. Next, the statement gives us something very useful a consensus map where the field is solid and where it's split. Let's walk through the high consensus anchors first because these are the things you can operationalize Monday morning.
High consensus meaning 10 or 11 of 11 votes, ultrasound guided vascular access, heparin with ACT at least three hundred seconds and giving heparin after vascular access before transseptal, meticulous sheath management, optimized catheter tissue contact, adequate lesion overlap (about 50% and this one is important. Keep total lesions as low as reasonably achievable explicitly to mitigate adverse events such as hemolysis. Then for device patients, reprogramming in patients at risk of harm and when ablating near coronaries, ST monitoring and urgent angiography availability. That's a solid set of operational anchors. It's also telling you something quietly.
PFA may be non thermal in concept but it is not consequence free. Sheaths, anticoagulation, contact, overlap and total dose still matter. Now let's move into the moderate consensus zone. Eight to nine of 11 votes. These are practical recommendations but they're not universally settled.
General anesthesia is preferred nine of 11. PFA should be the preferred system for PVI eighteleven, intracardiac echo where available eighteleven, lidocaine for cough suppression eighteleven, anticholinergic prophylaxis, eight of 11, no post PVI waiting period needed, eight of 11, renal and hemolysis, mitigation via fluids and biomarker checks in high burden cases, eight of 11, and device interrogation pre and post 10 of 11. Here's how I interpret this cluster. The committee is signaling that the workflow is converging but it's also admitting that a lot of this is still local practice dependent, resource dependent, and platform dependent. And then you have the low consensus zone.
Here's a good example, doing right pulmonary veins before left pulmonary veins to minimize vagal reactions. That got five of 11 votes and is explicitly not accepted by the majority. So when you read that don't hear it as dogma, hear it as some operators believe this helps and others don't. And that's exactly why vote transparency is useful. Okay, now we move into the core of the episode, the critical appraisal.
And I'm going to do this like we do in the lab, practical, platform aware and focused on what can hurt patients and what can surprise operators. Point number one. The statements tone that PFA should be the default is evidence supported in some contexts but over generalized in others. What the statement does well is it frames PFA as a coupled system, generator, waveform, catheter and it emphasizes instructions for use or IFU adherence. That matters because PFA is not a uniform exposure.
Where it can overreach is when global adoption is implied without fully accounting for infrastructure variability. The evidence base comes largely from trial protocols and high resource settings. Intracardiac echo availability, stable anesthesia support, robust post market surveillance, rapid IFU updates. So I'd separate two statements. One, PFA is highly promising and often preferred where infrastructure training and post market update pathways exist.
Two, PFA as default worldwide is not yet an evidence based equity aware conclusion. Point number two, platform neutral is not the same as platform informed. The statement acknowledges system heterogeneity but many recommendations read as if PFA is one uniform technology. In reality the complication signal is increasingly platform and protocol dependent and this is where the modern field has changed. Post market signals are not just noise, they are part of the evidence base.
A concrete example is the varipulse neurovascular signal management and the subsequent IFU and protocol changes. In my view a safety forward scientific statement should explicitly teach operators how to operationalize post market signals, what changes, how quickly and how to audit your local practice. Otherwise neutrality becomes omission. Point number three. Hemolysis and acute kidney injury.
The statement is directionally right but not operational enough. They correctly link hemolysis risk to system choice and lesion burden and they vote 10 of 11 to minimize lesion number to reduce adverse events such as hemolysis. They also suggest risk based hydration and lab surveillance in high burden cases. But here's what's missing for real world practice: a dose framework. What's the expected application range for PVI only versus PVI plus adjunctive lesions, a trigger beyond the vague phrase large number, and a risk stratification approach.
So here's how I'd operationalize this. Pre case, flag risk, chronic kidney disease stage three or worse, heart failure with strict fluid balance, baseline anemia, or hemoglobinopathy, or an anticipated high lesion count because you're planning PVI plus adjunct targets. In case, adopt one discipline that prevents dose creep. Fix geometry before repeating energy. Document the reason for every repeat.
Is it a gap? Is it contact? Is it a deliberate overlap strategy? Post case have clear triggers if lesion burden is high or if there's hemoglobinuria, Taylor fluids and check renal and hemolysis labs on a defined schedule. And importantly avoid blanket fluids in heart failure phenotypes.
Point number four. Airway and neuromuscular realities. This is where a clean sentence in a statement can become a messy moment in the lab. The statement votes 10 of 11 that routine phrenic monitoring is not necessary for standard endocardial PFA, but it also warns that excessive stacking near the phrenic nerve may cause persisting damage. Here's the nuance, prospective c map monitoring studies have reported subclinical phrenic nerve injury at rates far higher than overt clinical palsy and some patients don't fully recover by the end of the procedure.
So if you take routine monitoring is unnecessary and translate it into this can't happen That's a mistake. And there's another operational issue the statement does not highlight enough. Laryngospasm or airway obstruction during left superior PV energy delivery has been reported and is distinct from cough management. So practically your team needs a plan. How are you suppressing cough?
How are you managing vagal reactions? And if airway obstruction occurs, what's your rescue sequence? This is exactly why I argue even if the document is intentionally platform neutral, it should still include a dedicated section titled Post market safety signals and instructions for use or IFU driven protocol changes. Point number five. The esophagus.
The statement argues that routine esophageal monitoring or cooling is unnecessary in standard PVI. Reasonable, but there's an internal tension. If the same statement cautions against stacking near the esophagus and acknowledges system specific thermal profiles then a one size no monitoring stance becomes harder to defend as lesion sets expand. Here's my operational translation. Don't make esophageal strategy binary.
Codify selective strategies. Posterior wall, linear lesion sets, repeat posterior PV application, or platforms where there is concern for thermal footprint variability. Point number six, durability and what I call the acute endpoint trap. The statement supports overlap, minimizes waiting periods, and deprioritizes adenosine or non inducibility as routine endpoints. That's pragmatic efficiency, but it risks teaching operators to overtrust acute silence and entrance block as surrogates for irreversibility, especially early in the learning curve and in complex substrates.
So I want a missing paragraph that's basically called when to be more skeptical. Early operator learning curve enlarged left atrium or advanced atrial myopathy, redo AF ablation, posterior wall, or adjunctive lesion sets, and repeated applications due to poor contact or positioning. If you're in that bucket, consider that acute endpoints might be necessary but not sufficient. Point number seven. CIED interaction.
The statement provides good baseline advice. Avoid close proximity and direct contact. Interrogate pre and post. Reprogram high risk patients. But case reports and series now describe irreversible device damage under certain proximity and anatomy conditions, so we probably need an anatomic risk ladder.
PVI only is not the same risk as SVC, CTI, septal targets or ventricular targets, and we need explicit cautions about shock coils and close field delivery geometries. If I had to put a red flag box into the statement, it would read like this, ICD shock coils plus SVC or right atrial septal targets plus close field energy delivery equals highest risk geometry. Point number eight, silent cerebral lesions and catheter geometry. The consensus notes a silent cerebral emboli risk around ten to fifteen percent, but it misses a major opportunity to teach operators something practical. Silent lesion incidents can be highly dependent on catheter geometry.
Diffusion MRI assessments have shown a massive discrepancy. In one comparison, variable loop circular catheters were associated with silent lesions in about eighty six percent of patients, while circular multi electrode arrays were associated with lesions in about twenty two percent of patients. That's not a small difference. That's a geometry story and it reinforces why sheath management, anticoagulation discipline, air mitigation and platform specific technique are not optional details. So what's the synthesis?
Here's the summary I want you to carry into your next case. One, platform aware safety monitoring needs to be explicit including post market signals and instructions for use driven protocol changes. Two, we need dose planning frameworks that balance durability versus hemolysis risk with risk tiers and clear monitoring triggers. Three, phrenic monitoring guidance should be targeted not dismissive because subclinical injury and airway events are real operational issues. Four, global implementation should be resource tiered, meaning the workflow needs to adapt when general anesthesia, intracardiac echo, advanced imaging and robust follow-up are not reliably available.
And that leads to what I think is the right way to read this statement. Number one. Treat it as a high quality consensus workflow map for high resource systems. Number two treat every we recommend as a hypothesis plus vote math not a guideline grade mandate. Number three overlay it with platform aware post market vigilance because the field is already changing practice based on real world safety signals.
And number four is if you practice outside North America and Europe, translate it. Don't adopt it verbatim. With that we conclude our special edition of EP Edge journal watch. Thanks for listening to EP Edge Journal Watch. If you take just one message today let it be this: read the endpoints, watch the safety signals and keep asking what's next.
All details graphics and references are available on Substack at epedge.substack.com and also on the LinkedIn newsletter EP Edge Journal Watch. Subscribe, share it with a colleague and I'll see you in the next issue. Thanks and take care.