Atrial Tachycardia
Conditions
Keywords
Atrial Tachycardia, Atrial Fibrillation, Mapping, Ablation
Brief summary
Atrial tachycardia is a symptomatic arrhythmia, for which an effective treatment is a catheter ablation procedure. The goal of the Ripple AT-Plus study is to evaluate two methods of performing catheter ablation for atrial tachycardia. The main outcome assessed during the study is long-term recurrence of atrial tachycardia following the catheter ablation procedure.
Detailed description
Catheter based mapping of the electrical signals in the heart during atrial tachycardia can identify areas that require ablation in order to treat the arrhythmia. There are numerous methods by which to map atrial tachycardia. Isthmus guided ablation using Ripple Mapping is one such method, and has recently been demonstrated to improve diagnostic accuracy of mapping and therefore improve acute procedural outcomes (termination of the tachycardia). However, it is not known if improved acute procedural outcomes translate into long-term benefits for patients. At present, the recurrence rate following atrial tachycardia ablation is near 30%. We hypothesise that isthmus guided ablation using Ripple Mapping can reduce long-term recurrence following ablation as improved diagnostic accuracy of mapping can lead to more targeted, less extensive, ablation. Patients referred for catheter ablation of atrial tachycardia will be randomised to undergo the procedure by isthmus targeted approach using Ripple Mapping or conventional approach using local activation time. Otherwise, the catheters used to perform the mapping and ablation will be the same in both groups. After the procedure, follow up will occur at 1 year with a further Holter Montior. Any arrhythmia recurrence will be documented and the two arms will be compared for acute success, 12 month success, ablation required and procedure time.
Interventions
PROCEDURECatheter ablation of atrial tachycardia: Ripple Mapping guided.
Ripple Mapping is used to map the atrial tachycardia mechanism. Using the scar thresholding technique the Ripple Map is interpreted and catheter ablation directed to the site of the heart identified as putative to the arrhythmia mechanism. All ablation lesions are confirmed to have conduction block across them using Ripple Mapping. This can include lesions created at previous ablation procedures.
PROCEDURECatheter ablation of atrial tachycardia: Conventional mapping guided.
Conventional activation mapping is used to map the atrial tachycardia mechanism. The resultant (activation) map is interpreted and ablation directed to the site of the heart identified as putative to the arrhythmia mechanism. All ablation lesions are confirmed to have conduction block across them using conventional mapping. This can include lesions created at previous ablation procedures.
Sponsors
Imperial College Healthcare NHS Trust
Norfolk & Norwich University Hospital Trust
Nottingham University Hospitals NHS Trust
University Hospitals Plymouth NHS Trust
Blackpool Teaching Hospitals NHS Trust
Cardiff & Vale UHB
University Hospitals Sussex NHS Foundation Trust
Liverpool Heart and Chest Hospital NHS Foundation Trust
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
1. Referred for catheter ablation of AT by the direct care team, based on clinical indication. 2. Male or female, aged \>18 years old. 3. Able to consent for recruitment to the trial and the catheter ablation procedure.
Exclusion criteria
1. Contraindication to catheter ablation as deemed by the clinical team. 2. Typical atrial flutter or AF on ECG.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Atrial arrhythmia recurrence | 12 months | Any confirmed episode of atrial arrhythmia (\>30 seconds on Holter or 12 lead ECG) occurring in the 12 months after catheter ablation. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Acute success during the catheter ablation procedure by the first ablation set. | Procedure. | Atrial tachycardia termination (acute success) during ablation delivered to only target the diagnosed AT mechanism by the mapping approach used (first ablation set). |
| Acute success during the catheter ablation procedure without the need of entrainment. | Procedure. | Entrainment not required to confirm or exclude the diagnosis made by 3D electroanatomic mapping methods. |
| Procedure failure. | Procedure. | Inability to terminate atrial tachycardia during the catheter ablation procedure, requiring external electrical cardioversion to achieve sinus rhythm. |
| Total procedure time. | Procedure. | Procedure time measured from initiation of intracardiac mapping to catheter removal from the body. |
| Ablation required | Procedure. | Ablation required, measured using pre-defined ablation index or ablation line length. |
Countries
United Kingdom
Outcome results
None listed