High Power Radiofrequency Ablation for Atrial Flutter

(AITAF Trial)

Overseen By Stephen Wilton, MD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of Calgary

Must not be taking: Anti-arrhythmics, others

Disqualifiers: Congenital heart disease, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 1

Duration: 1 day

50 Participants Needed

Trial Summary

What is the purpose of this trial?

A randomized controlled trial will be conducted to evaluate the efficacy of Ablation Index-guided high power - short duration (HPSD) ablation compared to conventional power settings in Cavotricuspid Isthmus (CTI) dependent atrial flutter. Participants will be randomized to receive either AI-guided HPSD ablation at 50 Watts or conventional power settings at 30 Watts. Both arms will use the Carto 3D mapping system and the QDOT MICRO ablation catheter (Biosense Webster). An anatomically contiguous line will be created with \<6mm inter-lesion distance. After a standardized wait time of 30 minutes, ablation success will be assessed. The primary outcome is total radiofrequency ablation time. Secondary outcomes include procedural time, fluoroscopy time, safety outcomes, and 3-month freedom from recurrence. It is our expectation that HPSD will result in a shorter primary outcome.

Will I have to stop taking my current medications?

If you are taking anti-arrhythmic drugs like flecainide, sotalol, or amiodarone, you will need to stop them 3 days before the procedure and not restart them afterward. For other medications, the protocol does not specify.

What data supports the effectiveness of the treatment Ablation of the Cavo-tricuspid isthmus for typical Atrial Flutter?

Radiofrequency ablation of the cavo-tricuspid isthmus is highly effective, with success rates around 90-95% in treating atrial flutter, although the success can vary based on the complexity of the heart's anatomy. ^{1 2 3 4 5}

Is high power radiofrequency ablation for atrial flutter safe for humans?

Radiofrequency ablation for atrial flutter, which targets the cavo-tricuspid isthmus, is generally considered safe and effective, with a high success rate in preventing flutter recurrences. ^{2 4 6 7 8}

How does high power radiofrequency ablation for atrial flutter differ from other treatments?

High power radiofrequency ablation for atrial flutter is unique because it targets the cavo-tricuspid isthmus, a critical area for this type of arrhythmia, using a catheter to deliver energy that disrupts the abnormal electrical circuit. This method is effective in preventing recurrences and is considered safe, with a high success rate in treating typical atrial flutter. ^{2 3 8 9 10}

Research Team

George Veenhuyzen, M.D.

Principal Investigator

University of Calgary

Rory P Dowd, MBBS, MEng

Principal Investigator

University of Calgary

Eligibility Criteria

This trial is for individuals with a type of rapid heartbeat called atrial flutter. Participants should be suitable candidates for a procedure that burns (ablates) the area causing the flutter in their heart. Specific details on who can or cannot join are not provided, but typically involve health status and history.

Inclusion Criteria

Clinically determined by a cardiac electrophysiologist to have had at least one episode of CTI dependent atrial flutter

A heart specialist believes a specific heart procedure could help me.

Able and willing to comply with all protocol requirements

Exclusion Criteria

I have a congenital heart condition.

I am not pregnant or breastfeeding.

I will be under general anesthesia for my procedure.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo radiofrequency ablation with either 30W or 50W power settings to achieve CTI block

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness, including recurrence of atrial flutter and presence of durable CTI block

3 months

Follow-up visits as needed, including ECGs and Holter monitoring

Treatment Details

Interventions

• Ablation of the Cavo-tricuspid isthmus for typical Atrial Flutter

Trial Overview The study compares two ways to perform heart ablation: one uses high power at 50 Watts for a short time, while the other uses standard power at 30 Watts. The goal is to see if higher power makes the procedure quicker without compromising safety or effectiveness.

Participant Groups

Group I: 50 Watt Experimental Treatment 1 Intervention

Power set to 50 Watts

Group II: 30 Watt Active Control 1 Intervention

Power set to 30 Watts

Who Is Running the Clinical Trial?

University of Calgary

Lead Sponsor

Trials

827

Recruited

902,000+

References

1. France pubmed.ncbi.nlm.nih.gov

[Relation between cavo-tricuspid isthmus anatomy studied by transesophageal echocardiography and the immediate outcome of radiofrequency ablation of common atrial flutter]. [2016]

2. Chile pubmed.ncbi.nlm.nih.gov

[Results of radiofrequency ablation of the inferior vena cava-tricuspid valve isthmus for atrial flutter]. [2019]

3. United States pubmed.ncbi.nlm.nih.gov

Electromagnetic versus fluoroscopic mapping of the inferior isthmus for ablation of typical atrial flutter: A prospective randomized study. [2022]

4. England pubmed.ncbi.nlm.nih.gov

Simple and efficient identification of conduction gaps in post-ablation recurring atrial flutters. [2006]

5. Italy pubmed.ncbi.nlm.nih.gov

Outcome of the elective or online radiofrequency ablation of typical atrial flutter. [2023]

6. Portugal pubmed.ncbi.nlm.nih.gov

Atrial flutter ablation: correlation between isthmic activation times and flutter cycle. [2004]

7. United States pubmed.ncbi.nlm.nih.gov

Usefulness of the noncontact mapping system to elucidate the conduction property for the treatment of common atrial flutter. [2012]

8. Italy pubmed.ncbi.nlm.nih.gov

Atrial flutter: arrhythmia circuit and basis for radiofrequency catheter ablation. [2007]

9. Germany pubmed.ncbi.nlm.nih.gov

Identification and ablation of atypical atrial flutter. Entrainment pacing combined with electroanatomic mapping. [2004]

10. Netherlands pubmed.ncbi.nlm.nih.gov

Successful Ablation of Cavotricuspid Isthmus-dependent Atrial Flutter Guided by Contact Force Vector in a Patient After a Tricuspid Valve Replacement. [2020]