Randomized Study of Radiofrequency- vs. Cryo-Ablation for Typical Isthmus-Dependent Atrial Flutter

Study Overview
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Brief Summary
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This randomized study compares two energy sources for the catheter based ablation of typical isthmus-dependent atrial flutter: The (standard) radiofrequency (RF) ablation technique and the cryo-ablation technique regarding the acute and long term efficacy and safety.

Detailed Description
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This randomized study compares two energy sources for the catheter based ablation of typical isthmus-dependent atrial flutter: The (standard) radiofrequency (RF) ablation technique and the cryo-ablation technique. The RF ablation of typical atrial flutter has become a standard approach with very high curing rates and low complication incidence. However, ablation with RF is painful since the underlying cardiac tissue heats up (up to 70-80°C inside the tissue) and especially the target of ablation in typical atrial flutter, the so-called cavo-tricuspid isthmus, is a very pain-receptive area. Cryo-ablation, which destroys tissue by freezing it down to -80 to -90°C, is thought to be less painful or even painless with the same efficacy than RF ablation. The acute and long term (6 months follow-up, non-invasive) efficacy and safety is the combined endpoint.

Official Title
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Multicenter Prospective Randomized Clinical Study Comparing Radiofrequency- vs. Cryo-Ablation in Typical Isthmus-Dependent Atrial Flutter

Conditions
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Atrial Flutter

Intervention / Treatment
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* Procedure: RF ablation of the cavo-tricuspid isthmus
* Procedure: cryo ablation of the cavo-tricuspid isthmus
* Procedure: irrigated tip radiofrequency ablation of the cavo-tricuspid isthmus
* Procedure: cryo 6.5mm tip ablation of the cavotricuspid isthmus


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age between 18 and 80 years documented atrial flutter which is most probably typical isthmus dependent atrial flutter informed written consent Exclusion Criteria: prior ablation for atrial flutter concomitant arrhythmia which is treated during the same ablation procedure prior MAZE operation contra indication for catheterization physical or psychiatric disorder making participation in the study impossible pregnancy prior participation in the study participation in another study

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1<br>8mm tip ablation catheter for ablation of cavotricuspid isthmus | Procedure: RF ablation of the cavo-tricuspid isthmus<br>* 8mm tip ablation catheter is used for the radiofrequency ablation of the cavo-tricuspid isthmus in typical atrial flutter<br>|
| Experimental: 2<br>irrigated tip ablation catheter for ablation of cavotricuspid isthmus | Procedure: irrigated tip radiofrequency ablation of the cavo-tricuspid isthmus<br>* irrigated tip ablation catheter is used for the radiofrequency ablation of the cavo-tricuspid isthmus in typical atrial flutter<br>|
| Experimental: 3<br>cryo 10mm tip ablation catheter for ablation of cavotricuspid isthmus | Procedure: cryo ablation of the cavo-tricuspid isthmus<br>* Cryo 10mm tip ablation catheter is used for the cryo ablation of the cavo-tricuspid isthmus in typical atrial flutter<br>|
| Experimental: 4<br>Cryo 6.5mm tip ablation catheter for ablation of cavotricuspid isthmus | Procedure: cryo 6.5mm tip ablation of the cavotricuspid isthmus<br>* cryo 6.5mm tip ablation catheter is used for the cryo ablation of the cavo-tricuspid isthmus in typical atrial flutter<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Acute Efficacy (bidirectional cavotricuspid isthmus block) |  | bidirectional cavotricuspid isthmus block | 
| Long-term efficacy (6 months FU freedom of typical atrial flutter) |  | 6 months | 
| Mortality |  | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patients' pain scores during ablation |  | while hospitalisation | 
| Safety of ablational devices |  | 6 months |