NCT01587404

Brief Summary

Until recently, there was no way of telling how firmly the tip of the catheter was in contact with the heart and how this contact was orientated. The electrical signals measured through the catheters, known as electrograms, are used to guide the sites and duration of ablation, but the effect of catheter contact and orientation on these signals in human heart muscle that is fibrillating is not known. New catheters have now been developed which can measure the force of contact at their tip: using these, the investigators will examine how contact force affects the electrical behaviour of heart muscle tissue in atrial fibrillation. The effect the force of contact has on the electrogram recorded will also be investigated. In so doing we hope to gain a better understanding of the relationship between tissue contact and the electrograms we measure and in so doing improve the safety and effectiveness of ablation procedures. Hypothesis: Catheter contact force and orientation have a significant impact on the characteristics of bipolar electrograms in the fibrillating human atrium.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
55

participants targeted

Target at below P25 for phase_4 atrial-fibrillation

Timeline
Completed

Started Apr 2012

Longer than P75 for phase_4 atrial-fibrillation

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

April 1, 2012

Completed
22 days until next milestone

First Submitted

Initial submission to the registry

April 23, 2012

Completed
7 days until next milestone

First Posted

Study publicly available on registry

April 30, 2012

Completed
5.1 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

May 31, 2017

Completed
1.2 years until next milestone

Study Completion

Last participant's last visit for all outcomes

August 21, 2018

Completed
Last Updated

September 30, 2019

Status Verified

September 1, 2019

Enrollment Period

5.2 years

First QC Date

April 23, 2012

Last Update Submit

September 26, 2019

Conditions

Atrial Fibrillation

Keywords

Atrial FibrillationElectrogramAblationContact Force

Outcome Measures

Primary Outcomes (1)

  • Electrogram characteristics

    Effect of changes in contact force and orientation on: slew rate, local mean cycle length, electrogram complexity and fractionation index, dominant frequency, organisation index, CFAE grade, interval confidence level, shortest complex interval and average complex interval

    Baseline and 30 seconds

Secondary Outcomes (4)

  • Electrogram amplitude

    Baseline and 30 seconds

  • Electrogram responses to ablation

    Baseline and 30 seconds

  • Ablation Power (Watts)

    Baseline and 30 seconds

  • Electrogram Contact Mapping

    During Study

Study Arms (2)

Constant Catheter Contact Force

EXPERIMENTAL

No alteration of catheter contact force during recording period

Device: THERMOCOOL® SMARTTOUCH™ Catheter (including Surround Flow)

Variable catheter contact force

EXPERIMENTAL

change in contact force from low to high after 30seconds of recording.

Device: THERMOCOOL® SMARTTOUCH™ Catheter (including Surround Flow)

Interventions

THERMOCOOL® SMARTTOUCH™ Catheter (including Surround Flow)DEVICE

Variable contact force as measured at the catheter tip within the left atrium

Constant Catheter Contact ForceVariable catheter contact force

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Persistent or paroxysmal atrial fibrillation
  • Listed for ablation of atrial fibrillation on clinical grounds

You may not qualify if:

  • Contraindication to catheter ablation
  • Contraindication to anticoagulation
  • Contraindication to TOE

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

St Bartholomew's Hospital

London, EC1A 7BE, United Kingdom

Location

Related Publications (2)

  • Ullah W, Hunter RJ, Baker V, Ling LH, Dhinoja MB, Sporton S, Earley MJ, Schilling RJ. Impact of Catheter Contact Force on Human Left Atrial Electrogram Characteristics in Sinus Rhythm and Atrial Fibrillation. Circ Arrhythm Electrophysiol. 2015 Oct;8(5):1030-9. doi: 10.1161/CIRCEP.114.002483. Epub 2015 Jul 7.

    PMID: 26152560DERIVED

  • Ullah W, Hunter RJ, Baker V, Dhinoja MB, Sporton S, Earley MJ, Schilling RJ. Target indices for clinical ablation in atrial fibrillation: insights from contact force, electrogram, and biophysical parameter analysis. Circ Arrhythm Electrophysiol. 2014 Feb;7(1):63-8. doi: 10.1161/CIRCEP.113.001137. Epub 2014 Jan 18.

    PMID: 24443504DERIVED

MeSH Terms

Conditions

Atrial Fibrillation

Condition Hierarchy (Ancestors)

Arrhythmias, CardiacHeart DiseasesCardiovascular DiseasesPathologic ProcessesPathological Conditions, Signs and Symptoms

Study Officials

  • Richard J Schilling, MD

    Professor of Cardiology and Electrophysiology St Barts Hospital and Queen Mary University

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
phase 4
Allocation
RANDOMIZED
Masking
SINGLE
Who Masked
OUTCOMES ASSESSOR
Purpose
DIAGNOSTIC
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

April 23, 2012

First Posted

April 30, 2012

Study Start

April 1, 2012

Primary Completion

May 31, 2017

Study Completion

August 21, 2018

Last Updated

September 30, 2019

Record last verified: 2019-09

Locations

GB(1)