Shape vs Substrate in AF

NCT05993104 | Withdrawn

• 1 other identifier: 16749
• Study Type: observational
• Target: N/A
• Locations: 1 country
• Sites: 1

Brief Summary

Atrial fibrillation (AF) is an abnormal heart rhythm which originates from the top two chambers (atria) of the heart. It can cause significant symptoms and have severe consequences such as stroke. Catheter ablation is a treatment for AF. It is minimally invasive, involving thin tubes known as catheters, being inserted through a blood vessel in the groin and passed to the heart under X-ray guidance. Once in the heart, regions of tissue believed responsible for the abnormal heart rhythm can be identified, and hot or cold energy used to create scar at these areas, preventing the abnormal rhythm. Identifying these regions is a key challenge in making the treatment as effective as possible. The investigators believe that there may be a change in the shape of a participant's atria in these regions and as such identifying and treating areas of abnormal shape may be beneficial. To investigate this, the study team propose three phases. The first, uses previously collected data to make a model of what is average atrial geometry in AF. Investigators will then compare individual participants' atrial geometries to this average shape to identify areas of geometric abnormality and see how these correspond to areas of abnormal electrical activity. In the second phase, investigators will collect new data on how much atrial geometry changes during catheter ablation procedures. Finally, in the third phase, investigators will investigate whether including geometric assessment in the catheter ablation procedure is feasible from a work flow perspective.

Conditions

Atrial Fibrillation; Atrial Fibrillation, Persistent

Outcome Measures

Primary Outcomes (6)

• Regional deformation between participant left atrial geometry and SSM (study phase 1).

  Left atria will be partitioned into 6 segments: anterior, posterior, inferior, roof, septal and lateral. Regional deformation is defined by the mean proximity of these segments from their respective closest locations on the SSM.

  1 year.

• Location of AF drivers defined by AcQTrack (study phase 1).

  Location defined using 6 segment model as described above (outcome 1).

  1 year.

• Frequency of AF drivers defined by AcQTrack (study phase 1).

  Frequency of AcQTrack phenomena reported as #/s.

  1 year.

• Regional change in AcQMap left atrial geometry during ablation procedure (study phase 2).

  Regional change defined using 6 segments as per outcome 1. Calculated as mean proximity of these segments during repeated geometry collection from their respective closest locations during initial geometry collection.

  2 years.

• Completion of additional shape analysis (study phase 3).

  3 years.

• Additional procedure time (study phase 3).

  3 years.

Study Arms (3)

Retrospective observational

Retrospective observational arm recruiting \>50 participants, utilising data already collected as part of standard clinical care.

Other: Statistical shape analysis

Prospective single-arm

Prospective single-arm recruiting 20 participants undergoing AcQMap guided ablation.

Diagnostic Test: Intrachamber ultrasound

Feasibility study

Feasibility study recruiting 10 participants.

Other: Statistical shape analysis

Interventions

Intrachamber ultrasound DIAGNOSTIC_TEST

Ultrasound left atrial geometry collecting using AcQMap.

Prospective single-arm

Statistical shape analysis OTHER

Statistical shape analysis tools used to investigate left atrial geometry

Feasibility study; Retrospective observational

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Participants with atrial fibrillation referred to a tertiary hospital (John Radcliffe, Oxford) for ablation.

You may qualify if:

• Retrospective component:
• Participant gave consent for anonymised data being utilised for clinical research at time of procedure.
• Male or Female, aged 18 years or above.
• Previous AcQMap guided ablation for paroxysmal or persistent atrial fibrillation.
• Prospective component:
• Participant is willing and able to give informed consent for participation in the study.
• Male or Female, aged 18 years or above.
• Diagnosed with paroxysmal or persistent atrial fibrillation and planned for an AcQMap guided catheter ablation procedure.

You may not qualify if:

• Congenital cardiac abnormality.
• Any other significant disease or disorder which, in the opinion of the Investigator, may either put the participant at risk because of participation in the trial, or may influence the result of the trial, or the participant's ability to participate in the trial.

Sponsors & Collaborators

• Oxford University Hospitals NHS Trust: lead

Study Sites (1)

John Radcliffe Hospital

Oxford, Oxfordshire, OX3 9DU, United Kingdom

Location

MeSH Terms

Conditions

Atrial Fibrillation

Condition Hierarchy (Ancestors)

Arrhythmias, Cardiac; Heart Diseases; Cardiovascular Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Tim Betts, MD MBChB FRCP

  Oxford University Hospitals NHS Trust

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: CASE ONLY
• Time Perspective: OTHER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor of Cardiovascular Medicine

Study Record Dates

• First Submitted: July 5, 2023
• First Posted: August 15, 2023
• Study Start: January 1, 2024
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): September 1, 2026
• Last Updated: February 21, 2024

Record last verified: 2024-02

Locations

GB (1)