Surreal illustration of a heart with fading circuitry, representing vanishing heart arrhythmias.

Vanishing Act: How New Tech Zaps Hidden Heart Arrhythmias

Jordan Keane in Health & Wellness December 2025 • 4 min read.

"Innovative software helps doctors pinpoint and eliminate elusive PVCs, even under anesthesia, offering new hope for heart rhythm control."

Frequent premature ventricular contractions (PVCs) and non-sustained ventricular tachycardia can negatively impact heart function, leading to palpitations, dizziness, and, in rare cases, syncope. When intervention is necessary, ablation—a procedure to eliminate the source of these arrhythmias—is often performed under general anesthesia or conscious sedation, especially in children.

However, anesthesia presents a significant challenge: it can suppress spontaneous ventricular ectopy, making it difficult to locate the precise origin of the arrhythmia. Traditional methods rely on activation-time mapping and subjective comparison of paced and targeted QRS morphology, which can be unreliable when arrhythmias are infrequent.

But what if there was a way to overcome the limitations imposed by anesthesia? Recent research explores a quantitative approach using PaSo software (Carto 3, Biosense-Webster) to enhance the accuracy of pace-mapping, even when spontaneous arrhythmias are scarce. This article delves into this innovative technique and its potential to improve the success of PVC ablation.

Pinpointing the Problem: How Does the Technology Work?

Surreal illustration of a heart with fading circuitry, representing vanishing heart arrhythmias.

The study, conducted at Children's National Health System in Washington, DC, involved 24 patients (26 procedures) undergoing ablation for frequent ventricular arrhythmias. When activation-time (AT) mapping was limited due to infrequent arrhythmias, pace-mapping was performed using the PaSo software. This software quantitatively compares the morphology of paced QRS complexes to the targeted PVC morphology, aiding in the localization of the arrhythmia's origin.

Here’s a closer look at how the process unfolds:

Initial Assessment: Patients were monitored before anesthesia to identify any naturally occurring arrhythmias.
Anesthesia Management: Anesthesia was administered based on patient maturity and preference, ranging from general anesthesia to conscious sedation.
Electrophysiology Study: Access to the heart was gained through femoral veins and arteries. Catheters were used to map the heart and identify the PVC origin.
Pace-Mapping with PaSo: When AT mapping was insufficient, pace-mapping was performed, with the PaSo software providing a quantitative assessment of QRS morphology match.
Ablation: Once the optimal site was identified (typically with >92% similarity), radiofrequency or cryoablation was used to eliminate the arrhythmia.

The results showed that even with reduced spontaneous VA frequency due to anesthesia, successful ablation was still achievable using pace-mapping facilitated by the PaSo software. Specifically, a high QRS match (average 96±2%) was associated with successful ablation.

The Future of Heart Rhythm Treatment

This research offers a promising solution to a common challenge in arrhythmia ablation: the suppression of spontaneous arrhythmias by anesthesia. By using quantitative morphology-matching software, doctors can more accurately locate and eliminate PVCs, even when they are 'vanishing' due to anesthesia.

The implications of this technology extend beyond improved success rates. It also opens the door for:

<ul> <li>Reduced Procedure Times: More accurate mapping could lead to quicker identification of the arrhythmia source, shortening procedure times.</li> <li>Improved Patient Outcomes: By overcoming the limitations of anesthesia, more patients could benefit from successful ablation.</li> <li>Wider Applicability: The technique could be particularly valuable in pediatric patients, where anesthesia is often necessary.</li> </ul>

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1111/pace.13186, Alternate LINK

Title: Ablation Of The Vanishing Pvc, Facilitated By Quantitative Morphology-Matching Software

Subject: Cardiology and Cardiovascular Medicine

Journal: Pacing and Clinical Electrophysiology

Publisher: Wiley

Authors: Jeffrey P. Moak, Kohei Sumihara, Jonathan Swink, Sridhar Hanumanthaiah, Charles I. Berul

Published: 2017-09-29

Everything You Need To Know

What are premature ventricular contractions (PVCs) and how does new technology address challenges in their treatment?

Frequent premature ventricular contractions (PVCs) and non-sustained ventricular tachycardia can cause palpitations and dizziness, and in rare instances, syncope. Ablation can address these issues, but it's often performed under anesthesia, which can make it hard to find the source of the arrhythmia. Quantitative morphology-matching software provides a new approach. PaSo software allows doctors to accurately locate and eliminate PVCs, even when anesthesia hides the problem.

How does the quantitative morphology-matching software, known as PaSo software, enhance the accuracy of pace-mapping?

PaSo software is a tool used with the Carto 3 system by Biosense-Webster. It quantitatively compares the shape of paced QRS complexes to the shape of the targeted PVC morphology. This helps doctors pinpoint the exact location of the arrhythmia's origin, making pace-mapping more accurate even when spontaneous arrhythmias are scarce.

Can you explain the process of ablation using PaSo software, specifically detailing how doctors locate and eliminate arrhythmias?

During ablation, doctors gain access to the heart using catheters through femoral veins and arteries. If activation-time mapping is insufficient, they use pace-mapping. PaSo software assesses how well the paced QRS complexes match the targeted PVC morphology. Once a site with high similarity (typically >92%) is found, radiofrequency or cryoablation is used to eliminate the arrhythmia.

What were the key findings of the study regarding the success of ablation when using pace-mapping facilitated by PaSo software?

The study showed that successful ablation was achievable with pace-mapping supported by PaSo software, even when anesthesia reduced the frequency of spontaneous ventricular arrhythmias. A high QRS match (average 96±2%) was associated with successful ablation, indicating that PaSo software enhances the accuracy of pace-mapping under anesthesia. This offers hope for better heart rhythm control.

Beyond the immediate benefits of PaSo software in arrhythmia ablation, what future research directions could further improve heart rhythm treatments?

This research focused on using PaSo software to improve the accuracy of pace-mapping during ablation procedures for ventricular arrhythmias. While the research highlights the benefits of quantitative morphology-matching in overcoming challenges posed by anesthesia, future research could explore the long-term outcomes of patients treated with this approach and investigate its applicability to other types of arrhythmias or patient populations. Also, research should explore how these findings compare to ablation performed without anesthesia.