Cryoablation of the Retrograde Fast Pathway as Treatment for AVNRT

Early Phase 1

• Conditions: Atrioventricular Node Arrhythmia
• Interventions: Procedure: Cardiac catheter ablation

• Registration Number: NCT04122807
• Lead Sponsor: Lawson Health Research Institute

Brief Summary

In this study a new technique for ablation in atrioventricular nodal reentrant tachycardia using cryo-energy will be studied in cases where the standard approach has higher risk.

Detailed Description

Atrioventricular nodal reentrant tachycardia (AVNRT) is the most common cause of fast heartbeats in young people. People with AVNRT have two pathways within the heart, the fast pathway (FP) and slow pathway (SP). A treatment for AVNRT is ablation (burning or freezing) of the SP. This can be done with either radiofrequency or cryo-energy. A complication which occurs in 1% of cases is AV block (AVB), meaning the person needs a pacemaker.

Slow pathway ablation is a problem in people when the electrocardiogram (ECG) shows a long PR interval, with greater rates of AVB. This accounts for 5% of AVNRT cases. A possible solution is to treat the FP with cryo-energy and leave the SP intact. This pilot study aims to show this is safe and effective.

Study Timeline

• Study First Submitted: 2019-10-02
• Study First Submitted QC: 2019-10-09
• Study First Posted: 2019-10-10
• Status Verified: 2019-11
• Study Start: 2019-11
• Last Update Submitted: 2019-11-18
• Last Update Posted: 2019-11-20
• Primary Completion: 2021-12
• Study Completion: 2021-12

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 20

Inclusion Criteria

• Documented supraventricular tachycardia (SVT)
• Planned to undergo electrophysiology (EP) study and ablation
• PR interval on ECG <220ms (Group 1) or >220ms (Group 2)

Exclusion Criteria

• Pregnancy
• Age <18 years
• Inability to provide consent
• High likelihood of tachycardia mechanism other than AVNRT (e.g. Pre-excitation on surface ECG, atrial tachycardia)

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Ablation	Cardiac catheter ablation	Mapping and ablation of the retrograde fast pathway with cryotherapy
Mapping	Cardiac catheter ablation	Standard treatment involving ablation of the slow pathway with cryotherapy

Primary Outcome Measures

Name	Time	Method
Termination of AVNRT	One day	Number of participants where cryotherapy terminates AVNRT

Secondary Outcome Measures

Name	Time	Method
Incidence of AV block	1 year	Number of participants where AV block is observed
Vascular complications	1 year	Number of participants with groin hematoma or fistula requiring intervention following procedure
Cardiac tamponade	1 year	Number of participants with pericardial effusion and/or tamponade following procedure
Freedom from recurrence	1 year	Number of participants with no recurrence of AVNRT during follow-up

Trial Locations

Locations (1)

Lawson Health Research Institute; 🇨🇦 London, Ontario, Canada