Subscribe
Share
Share
Embed
Welcome to EP Edge Journal Watch — where cardiac electrophysiology meets evidence, precision, and perspective.
Hosted by Dr. Niraj Sharma, this bi-weekly podcast distills high-impact cardiovascular and EP research into clear, clinically meaningful insights. Each episode goes beyond headlines and abstracts to uncover what new studies actually mean for patient care, decision-making, and the future of electrophysiology.
What EP Edge Journal Watch stands for:
Evidence-based practice
Precision electrophysiology
A forward-thinking, edge-driven approach to how we interpret and apply data in real-world clinical settings.
Whether you’re an electrophysiologist, cardiologist, researcher, trainee, or allied health professional, EP Edge Journal Watch brings you the signal — not the noise. Expect sharp summaries, thoughtful commentary, and practical takeaways designed for the busy clinician who wants to stay ahead of the curve
Welcome to a special edition of EPH Journal Watch. I'm Doctor Sharma and today we are marking an important inflection point in the evolution of pulsed field ablation. With the release of the one year investigational device exemption data from the Vault trial, we now, for the first time in The United States, have twelve month outcomes across every major pulsed field ablation system. This matters because early feasibility and short term safety are no longer the question. What defines clinical maturity is durability.
Niraj Sharma:And durability demands one year data collected under structured surveillance. This special edition is not about ranking technologies, it's not about declaring winners, and it s certainly not about marketing claims. Instead, are going to step back and look at the entire USPFA landscape, system by system, trial by trial, through the lens of methodology, trial design, patient phenotype, monitoring intensity, ablation strategy, because when those variables differ, raw success rates are not interchangeable, and with the VOLT one year IDE data now available, the comparative picture is finally complete. Before we discuss individual systems, it is critical to establish how we should interpret these trials side by side. Across the USPFA ecosystem, we are not comparing like with like.
Niraj Sharma:Some trials are randomized against thermal ablation. Others are single arm IDE studies. Some mandate posterior wall isolation or linear lesions. Others restrict operators to pulmonary vein isolation alone. Monitoring intensity ranges from weekly trans telephonic recordings to bi weekly to monthly surveillance, and endpoints differ.
Niraj Sharma:Composite effectiveness includes not just arrhythmia recurrence but cardioversion, repeat ablation, antiarrhythmic escalation, and procedural failure. Rhythm only freedom from atrial arrhythmias tells a different story, often a more optimistic one. If we fail to account for these differences, we risk drawing conclusions that the data simply do not support. With that context, let's walk through The US systems, starting with FerroPulse. The FerroPulse pentaspline system is supported by two pivotal datasets: ADVENT for paroxysmal atrial fibrillation and ADVENTage AF for persistent disease.
Niraj Sharma:ADVENT was a randomized non inferiority trial comparing PFA to thermal ablation. Pulmonary vein isolation was the sole strategy. Monitoring intensity was among the highest we have seen. Weekly transtelephonic recordings plus extended Holter monitoring at six and twelve months. At one year, composite effectiveness was approximately seventy three percent with rhythm only freedom from atrial arrhythmia closer to seventy eight percent.
Niraj Sharma:Safety events were uncommon and notably there were no esophageal fistulas or persistent phrenic nerve injuries. AF examined persistent atrial fibrillation but with a very different strategy. Posterior wall isolation was mandatory, in addition to pulmonary vein isolation. Despite this more extensive lesion set, one year effectiveness was approximately sixty three percent, with rhythm only freedom near sixty six percent. The takeaway here is important: adding lesion complexity does not guarantee higher durability, especially when monitoring remains intensive.
Niraj Sharma:The Sphere nine system introduces a different philosophy. It is a focal lattice tip catheter, capable of delivering both radiofrequency and pulsed field energy, with considerable flexibility in lesion design. Early feasibility data demonstrated strong one year rhythm outcomes, but the more informative comparison comes from the SPHERE per AF randomized trial. This study focused on persistent atrial fibrillation, allowed extensive linear ablation, and compared SPHERE9 directly to RF. Monitoring intensity was lower than Advent, monthly rather than weekly.
Niraj Sharma:At one year, composite effectiveness approached seventy four percent, with rhythm freedom near seventy seven percent. These are excellent outcomes, but they must be interpreted in the context of both lesion flexibility and reduced monitoring frequency. This trial underscores a recurring theme: success rates rise as surveillance intensity falls. The Verapulse system occupies a middle ground in this landscape. ADMIRE was a single arm IDE trial in paroxysmal atrial fibrillation focused on pulmonary vein isolation using a variable loop circular catheter.
Niraj Sharma:Monitoring was intensive early, with weekly recordings for the first five months, then transitioned to monthly surveillance. One year composite effectiveness was approximately seventy five percent, with rhythm only freedom in a similar range. Safety outcomes were generally favorable, though tamponade and stroke events did occur. The lesson from ADMIRE is balance: reasonable durability, moderate monitoring, and outcomes that sit squarely between the most and least intensive designs. There is one additional point worth addressing with Verapulse, and it's an important one from a post market learning perspective.
Niraj Sharma:Following early commercial use, an increased signal for periprocedural stroke was observed. This was not attributed to the pulsed field energy itself, but rather to catheter related factors, particularly flow dynamics and thrombus formation risk. In response, the system underwent a deliberate and significant change in its irrigation and flow strategy. The baseline flow rate was increased to 30 milliliters per minute. This adjustment was designed to mitigate thromboembolic risk by improving catheter cooling, reducing stasis, and minimizing clot formation during energy delivery.
Niraj Sharma:This event serves as a broader reminder: pulsed field ablation systems are not immune to device specific learning curves and post launch vigilance, rapid signal detection, and iterative design changes remain essential, even in a non thermal era. And this brings us to VOLT. The VOLT AF IDE trial completes The US one year PFA dataset. VOLT is unique in several ways. It is a balloon in basket system, mandates pulmonary vein isolation only, and applies that strategy to both paroxysmal and persistent atrial fibrillation.
Niraj Sharma:Monitoring was biweekly, less frequent than Advent, more frequent than SPHER per AF. In paroxysmal atrial fibrillation, Volt demonstrated the highest numeric one year success rates reported, exceeding eighty percent with no primary safety events. In persistent atrial fibrillation, outcomes were more modest but notably competitive, despite a PVY only strategy in a higher risk population. The significance of VOLT is not that it outperforms other systems, it is that it proves durable, one year outcomes are achievable with simplified lesion sets, deep energy delivery and acceptable safety. When we step back and view these trials together, several patterns emerge.
Niraj Sharma:First, monitoring intensity matters enormously. Weekly surveillance consistently lowers apparent success rates. Second, lesion complexity does not linearly translate into higher durability. Third, pulsed field ablation has now demonstrated reproducible one year safety across platforms. And finally, persistent atrial fibrillation remains a biologically complex disease, regardless of energy source.
Niraj Sharma:PFA is not a shortcut around atrial substrate, but it may offer a safer, more scalable foundation upon which future strategies are built. If you would like to review the full comparative tables, references and infographics, those are available in the EP EDGE Journal Watch on LinkedIn as well as on Substack at epedge.substack.com. If you have questions, comments or suggestions, you can reach me directly at epedgecast@gmail.com Thank you for listening, for engaging critically with emerging data, and for being part of the EP Edge community. This is Doctor.
Niraj Sharma:Sharma. Until next time, stay thoughtful, stay evidence driven and take care.