Fluoroscopic, Contact Force and Local Impedance With Ultra-high Density Mapping Guided Radiofrequency Ablation Comparison for cavoTricuspid Isthmus dependenT Atrial fluttER: the FLUTTER Study

NCT04434599 | Withdrawn DMC

• 1 other identifier: 281105
• Study Type: interventional
• Target: N/A
• Locations: 0 countries
• Sites: N/A

Brief Summary

Catheter ablation is a first-line treatment for patients with cavotricuspid isthmus (CTI) dependent atrial flutter (AFL; also known as typical AFL), a common arrhythmia. This is done using radiofrequency (RF) catheters and single-procedure success is approximately 95%. Ablation is often done using one of three methods:

1. 1.fluoroscopically, using X-rays to guide the operator to visualise catheter position within the heart. This method involves the most radiation exposure to patient and operator. Ablation is generally performed for a set time-period (eg. 30-60secs) to ensure each ablation lesion is successful.
2. 2.using a 3-dimensional mapping system which allows the catheters to be magnetically located and visualised on a monitor without X-rays, and using "contact force" (CF) sensing catheters. This requires minimal X-ray use, and by ensuring a minimum degree of force between catheter tip and the heart before applying RF for a set time-period (eg. 30 seconds), operators can be more confident of successful lesions.
3. 3.using an ultra-high density mapping system which uses magnetic tracking as above, but allows higher resolution visualisation of the cardiac electrical system with potential for improving procedure success; this has not yet been formally evaluated for AFL. Catheters using this method use "local impedance" (LI) instead of CF. This is a direct measure of heart tissue impedance with real-time changes during ablation. A minimum drop or plateau in the LI value during ablation allows confidence of lesion success, without the need to ablate for a pre-defined time-period. This could potentially reduce ablation time and subsequent complications, but has also not yet been formally compared to the above for this indication.

Conditions

Typical Atrial Flutter

Keywords

radiofrequency ablation; contact force; local impedance

Outcome Measures

Primary Outcomes (1)

• Time from first application of radiofrequency energy to confirmation of bidirectional cavotricuspid isthmus block

  Time from first application of radiofrequency energy to confirmation of bidirectional cavotricuspid isthmus block

  At time of procedure

Secondary Outcomes (8)

• Mean total ablation time to achieve bidirectional cavotricuspid isthmus block

  At time of procedure

• Mean total radiation exposure

  At time of procedure

• Mean total number of ablation lesions required to achieve bidirectional cavotricuspid isthmus block

  At time of procedure

• Number of cases where bidirectional cavotricuspid isthmus block was not achieved after the first pass of ablation

  At time of procedure

• Mean time taken for second pass ablation (with or without the use of 3D mapping) to achieve bidirectional cavotricuspid isthmus block

  At time of procedure

Study Arms (3)

Fluoroscopically guided ablation

ACTIVE COMPARATOR

These patients will receive one catheter ablation of typical atrial flutter by fluoroscopically guided radiofrequency ablation catheters

Device: Fluoroscopically guided ablation

Contact force guided ablation

ACTIVE COMPARATOR

These patients will receive one catheter ablation of typical atrial flutter by contact force guided radiofrequency ablation catheters using the CARTO 3D electroanatomic mapping system

Device: Contact force guided ablation

Local impedance guided ablation

ACTIVE COMPARATOR

These patients will receive one catheter ablation of typical atrial flutter by local impedence guided radiofrequency ablation catheters using the Rhythmia Ultra-high density 3D electroanatomic mapping system

Device: Local impedance guide ablation

Interventions

Fluoroscopically guided ablation DEVICE

Catheter ablation of the cavotricuspid isthmus using ablation catheters guided by fluoroscopy

Fluoroscopically guided ablation

Contact force guided ablation DEVICE

Catheter ablation of the cavotricuspid isthmus using ablation catheters guided by contact force measurement and 3D electroanatomic mapping

Contact force guided ablation

Local impedance guide ablation DEVICE

Catheter ablation of the cavotricuspid isthmus using ablation catheters guided by local impedance measurement and ultra-high density 3D electroanatomic mapping

Local impedance guided ablation

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients under the care of the NHS
• Aged 18-80 years
• Symptoms and 12-lead ECG suggestive of typical (cavotricuspid isthmus dependent) atrial flutter
• Due to undergo first-time cavotricuspid isthmus ablation (including as part of a combined ablation if also having pulmonary vein isolation for atrial fibrillation) on clinical grounds

You may not qualify if:

• Pre-procedure:
• Inability to given informed consent / lack of mental capacity
• Obesity (BMI \>40)
• Congenital heart disease or tricuspid valve abnormalities likely to prolong procedure time, including Ebstein anomaly, atrial septal defects, tricuspid valve repair or replacement, severe tricuspid valve regurgitation
• Inability or unwillingness to receive oral anticoagulation with a vitamin K antagonist (VKA) or non-VKA oral anticoagulant (NOAC)
• Previous cavotricuspid isthmus ablation procedure
• Known infiltrative cardiomyopathy
• Pregnancy
• Age \< 18 or \>80
• Inability to speak adequate English/need for an interpreter for study consent process
• Post procedure:
• \- arrhythmia mechanism found not to be cavotricuspid isthmus dependent atrial flutter

Sponsors & Collaborators

• University of Manchester: lead
• Manchester University NHS Foundation Trust: collaborator

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Investigator

Model Details: 114 patients randomised 1:1:1 to either fluoroscopically guided OR contact force guided OR local impedance guided radiofrequency catheter ablation of typical atrial flutter

Study Record Dates

• First Submitted: June 10, 2020
• First Posted: June 17, 2020
• Study Start: October 30, 2022
• Primary Completion: September 1, 2023
• Study Completion: January 1, 2024
• Last Updated: November 1, 2023

Record last verified: 2023-10

Data Sharing

• IPD Sharing: Will not share