Surreal illustration of a heart with a maze, symbolizing AFib surgery options.

Maze vs. Pulmonary Vein Isolation: Which AFib Surgery is Right for You?

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Nico Varela in Health & Wellness November 2025 • 5 min read.

"A new study suggests that a biatrial maze procedure may offer better long-term outcomes than pulmonary vein isolation for atrial fibrillation during mitral valve surgery."


Atrial fibrillation (AFib) is a common heart rhythm disorder affecting millions worldwide. For individuals with AFib who require mitral valve surgery, the decision of whether to include surgical ablation to treat the arrhythmia adds complexity. Surgical ablation aims to eliminate AFib by creating lesions in the heart tissue that block the abnormal electrical signals causing the irregular rhythm.

Two primary surgical approaches exist for AFib ablation: pulmonary vein isolation (PVI) and the biatrial maze procedure. PVI focuses on isolating the pulmonary veins, which are frequent sources of erratic electrical signals in AFib. The biatrial maze procedure involves creating a more extensive set of lesions in both atria (the upper chambers of the heart) to disrupt abnormal electrical pathways. While both techniques aim to restore normal heart rhythm, questions remain about their comparative effectiveness, especially over the long term.

A recent study published in The Journal of Thoracic and Cardiovascular Surgery sheds new light on this debate. Researchers analyzed data from a large clinical trial to compare the outcomes of patients with long-standing persistent AFib who underwent mitral valve surgery with either PVI or a biatrial maze procedure. This article breaks down the study's findings, offering insights into the potential benefits of each approach and what they might mean for patients like you.

Biatrial Maze vs. Pulmonary Vein Isolation: Understanding the Study

Surreal illustration of a heart with a maze, symbolizing AFib surgery options.

The study re-evaluated data from the Cardiothoracic Surgical Trials Network (CTSN) trial, which involved 260 patients with persistent or long-standing persistent AFib undergoing mitral valve surgery. Participants were randomized to mitral valve surgery alone or mitral valve surgery combined with surgical ablation. Those undergoing ablation were further randomized to either PVI or a biatrial maze.

For this analysis, the researchers focused on a subset of 228 patients (88%) who submitted transtelephonic monitoring (TTM) recordings, which captured weekly snapshots of their heart rhythm over 12 months. Using novel statistical methods, the team analyzed these TTM recordings to estimate the occurrence, burden, and prevalence of AFib, atrial flutter (AFL), and atrial tachycardia (AT) in each treatment group.

  • Transtelephonic Monitoring (TTM): Patients used a TTM device to transmit weekly heart rhythm recordings to a central monitoring facility.
  • Statistical Analysis: Researchers used advanced statistical models to analyze TTM data and estimate AFib occurrence and burden.
  • Study Endpoints: The primary focus was on freedom from AFib/AFL/AT, AF/AFL/AT load (proportion of TTM strips showing arrhythmia), and AF/AFL/AT prevalence.
The study was designed to overcome limitations of previous research, particularly the lack of power to detect differences between lesion sets when assessed with Holter monitoring alone. By leveraging the more frequent rhythm assessments provided by TTM, the researchers aimed to gain a more detailed understanding of the temporal patterns of AFib recurrence and the potential impact of different ablation strategies.

What This Means for AFib Patients

The findings suggest that a biatrial maze procedure may be associated with lower AF/AFL/AT prevalence than PVI in patients with long-standing persistent AFib undergoing mitral valve surgery. While these results are promising, it’s important to remember that they are based on statistical modeling and require confirmation in future studies. If you are facing mitral valve surgery and have AFib, discuss these findings with your cardiologist and cardiac surgeon to determine the best course of action for your individual situation. They can evaluate your specific case, consider the potential benefits and risks of each approach, and guide you toward the most appropriate treatment strategy.

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.

Everything You Need To Know

1

In atrial fibrillation (AFib) surgery, what's the key difference between pulmonary vein isolation and the biatrial maze procedure?

Pulmonary vein isolation (PVI) focuses on isolating the pulmonary veins to prevent erratic electrical signals that cause AFib. The biatrial maze procedure creates a more extensive set of lesions in both atria to disrupt abnormal electrical pathways. The biatrial maze procedure is more extensive, creating lesions in both atria, aiming for a more comprehensive disruption of abnormal electrical pathways compared to PVI, which targets only the pulmonary veins.

2

According to a recent study, what are the potential benefits of the biatrial maze procedure compared to pulmonary vein isolation (PVI) for patients with long-standing persistent AFib undergoing mitral valve surgery?

The recent study suggests that the biatrial maze procedure may lead to lower AF/AFL/AT prevalence compared to pulmonary vein isolation (PVI) in patients with long-standing persistent AFib undergoing mitral valve surgery. This indicates a potential advantage of the biatrial maze procedure in maintaining normal heart rhythm over the long term in this specific patient population.

3

How did researchers use transtelephonic monitoring (TTM) and statistical analysis in the study to assess the effectiveness of the atrial fibrillation (AFib) surgical procedures?

The study used transtelephonic monitoring (TTM) to collect weekly heart rhythm recordings from patients over 12 months. Researchers then applied advanced statistical models to these TTM data to estimate the occurrence, burden, and prevalence of AFib, atrial flutter (AFL), and atrial tachycardia (AT) in each treatment group. The utilization of TTM allowed for more frequent rhythm assessments, providing a more detailed understanding of AFib recurrence patterns compared to less frequent monitoring methods.

4

What were the key details of the study's design, including the patient population and randomization process, when comparing the biatrial maze procedure to pulmonary vein isolation (PVI)?

The study re-evaluated data from the Cardiothoracic Surgical Trials Network (CTSN) trial, which included 260 patients with persistent or long-standing persistent AFib undergoing mitral valve surgery. Participants were randomized to undergo mitral valve surgery alone or combined with surgical ablation, and those undergoing ablation were further randomized to either pulmonary vein isolation (PVI) or a biatrial maze procedure. By focusing on a subset of 228 patients with TTM recordings, the researchers aimed to compare the outcomes of PVI and the biatrial maze procedure in a real-world setting.

5

What were the study's primary endpoints for evaluating the success of each AFib surgical procedure, and what do these endpoints indicate about heart rhythm outcomes?

The primary focus was on freedom from AFib/AFL/AT, AF/AFL/AT load (proportion of TTM strips showing arrhythmia), and AF/AFL/AT prevalence. These endpoints provided a comprehensive assessment of the effectiveness of each surgical approach in restoring and maintaining normal heart rhythm. Freedom from AFib/AFL/AT indicates the overall success of the procedure, while AF/AFL/AT load and prevalence offer insights into the frequency and persistence of arrhythmia recurrence.

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