P-wave Duration and Local Potential as Predictors of AF Recurrence Following Pulmonary Vein Isolation (FOLLOW-AF)

Validation of an Algorithm Designed to Predict the Recurrence of AF After Pulmonary Vein Isolation Using P-wave Duration and Procedural Unipolar Atrial Local Potential Measurements

Atrial fibrillation (AF) is the most prevalent sustained cardiac arrhythmia worldwide and is associated with substantial morbidity, mortality, and healthcare utilization. Catheter ablation, most commonly pulmonary vein isolation (PVI), is an established rhythm control strategy for AF4.

Despite technological advances and the emergence of pulse field ablation (PFA), long-term AF recurrence after a first ablation procedure remains frequent, occurring in approximately 30-50% of patients5. Post-ablation follow-up strategies, including visit frequency, rhythm monitoring intensity, and Antiarrhythmic Drug management, vary widely across providers and institutions and are largely guided by subjective assessment rather than objective, science-based recurrence risk estimation6. In parallel, asymptomatic (silent) AF recurrence is exacerbated following ablation, limiting the reliability of symptom-driven follow-up7.

FOLLOW-AF is a retrospective, observational cohort study designed to validate the FollowGenius algorithm and evaluate the diagnostic performance in predicting AF recurrence based on atrial remodeling and vein isolation.

The cohort will be patients with paroxysmal or persistent AF who underwent PVI with the PFA modality.

Study Overview

• Status: Active, not recruiting
• Conditions: Atrial Fibrillation (Paroxysmal); Atrial Fibrillation (AF); Pulmonary Vein Isolation; Atrial Fibrillation Patients Treated With the FARAPULSE™ PFA System
• Intervention / Treatment: Device: AF Recurrence RIsk Assessment post pulmonary vein isolation

Detailed Description

Atrial fibrillation (AF) is the most prevalent sustained cardiac arrhythmia worldwide and is associated with substantial morbidity, mortality, and healthcare utilization.3 Catheter ablation, most commonly pulmonary vein isolation (PVI), is an established rhythm control strategy for symptomatic AF.4 Historically, this has been achieved using radiofrequency and thermal energy. However, more recently a new energy source known as pulsed field ablation (PFA) has been introduced. As PFA is tissue selective, it preserves the function of nearby structures such as the esophagus and phrenic nerve making it safer to use. As PFA is delivered in short bursts of high energy, it is also more efficient and leads to shorter procedures.

Despite technological advances and the emergence of pulse field ablation (PFA), long-term AF recurrence after a first ablation procedure remains frequent, occurring in approximately 30-50% of patients.5 Post-ablation follow-up strategies, including visit frequency, rhythm monitoring intensity, and anticoagulation management, vary widely across providers and institutions and are largely guided by subjective assessment rather than objective, science-based recurrence risk estimation.6 In parallel, asymptomatic (silent) AF recurrence is exacerbated following ablation, limiting the reliability of symptom-driven follow-up.7

The underlying causes of AF recurrence are broadly driven by two distinct, yet complementary, mechanisms:

1. Atrial Substrate Modification (Remodeling): Many patients have pre-existing atrial myopathy or remodeling due to long-standing hypertension, heart failure, or AF itself. This "diseased substrate" is prone to initiating and sustaining new AF triggers outside the pulmonary veins. P-wave duration, a simple, non-invasive marker from the surface ECG, is a well-established surrogate for this electrical and structural remodeling.2,9,10
2. PVI Isolation (Reconnection): The primary goal of ablation is to create durable, transmural lesions to isolate the pulmonary veins. If lesions are incomplete, electrical reconnection often occurs, allowing the original AF triggers to re-initiate arrhythmia. Residual local potentials measured during the ablation procedure are a suggested marker of incomplete lesion formation, predicting non-durability.1,11,12

Pulmonary vein isolation status is acquired by measuring the intra-cardiac residual electrical activity (local potential) in the vein, after PFA application. Residual local potentials will be extracted by the PF Analyzer module of the ECGenius™ System. Isolation status is defined based on thresholds from literature.

The FollowGenius algorithm is intended to allow AF recurrence risk stratification by providing risk scores (0-100).

FOLLOW-AF is a retrospective, observational cohort study designed to validate the prediction algorithm and evaluate the diagnostic performance in predicting AF recurrence based on atrial remodeling and vein isolation.

The cohort will be patients with paroxysmal or persistent AF who underwent PVI with the PFA modality.

• Study Type: Observational
• Enrollment (Estimated): 300

Contacts and Locations

Study Locations

• United States
  • New Jersey
    • Paramus, New Jersey, United States, 07652
      • The Valley Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Outpatient EHR

Description

Inclusion Criteria:

• Age ≥ 21 years
• Paroxysmal or persistent atrial fibrillation
• Underwent pulmonary vein isolation using pulse field ablation
• Patient record with pre-/post-ablation 12-lead ECGs and intra-procedural unipolar electrograms

Exclusion Criteria:

• Incomplete patient record:

  • Lack of 12-leads ECG recording or intracardiac electrograms
  • Lack of post-procedure follow-up assessment
  • Follow-up was less than 6 months
• Cardiac recording data incomplete or not of sufficient quality
• Cardiac anatomical variation such as Left Common, or Right Accessory

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Cohort 1 - Continuous monitoring; Subject with continuous post-procedure monitoring, such as ILR, pacemaker, and CRT device	Device: AF Recurrence RIsk Assessment post pulmonary vein isolation; AF Recurrence RIsk Assessment post pulmonary vein isolation based on PWD and Residual Local Potentials
Cohort 2 - Transient monitoring; Subject with transient monitoring, such as Holter, and tracking devices	Device: AF Recurrence RIsk Assessment post pulmonary vein isolation; AF Recurrence RIsk Assessment post pulmonary vein isolation based on PWD and Residual Local Potentials
Cohort 3 - Punctual monitoring; Subject with punctual monitoring, such as reported symptoms during physician visit	Device: AF Recurrence RIsk Assessment post pulmonary vein isolation; AF Recurrence RIsk Assessment post pulmonary vein isolation based on PWD and Residual Local Potentials

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Primary Objective	Evaluate predictive performance of a novel prognostic algorithm (called FollowGenius) combining p-wave duration and procedural unipolar atrial local potential measurements in predicting recurrence of AF after pulmonary vein isolation using PFA.	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Secondary Objective	Evaluate agreement between predicted risk and observed recurrence. Evaluate agreement between predicted risk and post-procedural AF burden. Evaluate contribution (weighting) of each individual predictors in AF recurrence risk score. Evaluate correlation of performance across different sub-group (paroxysmal vs persistent AF, first vs redo ablation, sex, age bands, monitoring modality)	6 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Outcome	Binary recurrence classification at 6 months (recurrence / no-recurrence). Time to Event at 6 months AF burden at 6 months Recurrence prediction score at 6 months (0-100)	6 months

Collaborators and Investigators

• Sponsor: CathVision ApS
• Collaborators: Valley Health System

Study record dates

Study Major Dates

• Study Start (Actual): April 13, 2026
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): August 1, 2026

Study Registration Dates

• First Submitted: March 10, 2026
• First Submitted That Met QC Criteria: March 10, 2026
• First Posted (Actual): March 13, 2026

Study Record Updates

• Last Update Posted (Actual): May 15, 2026
• Last Update Submitted That Met QC Criteria: May 13, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: atrial fibrillation; electrophysiology; AF; catheter; PFA; PVI; cardiac ablation
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arrhythmias, Cardiac; Pathological Conditions, Signs and Symptoms; Atrial Fibrillation
• Other Study ID Numbers: CVFOLLOW-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No