High-density Activation Mapping of the Slow Pathwayto Guide Catheter Ablation in Patients With Typical Atrioventricular Nodal Reentrant Tachycardia

Study Overview
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Brief Summary
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Atrioventricular nodal reentrant tachycardia (AVNRT) is the most common supraventricular tachycardia inducible during an electrophysiological study. Although ablative therapy proved to be the treatment of choice, little is known about the components of the tachycardia circuit. The aim of this study is to detect the presence and patterns of specific electrograms representing slow pathway (SP) potentials and to explore Koch's triangle pattern activation during sinus rhythm and/or atrial extraestimulus with a high-density mapping catheter in an attempt to clarify a fast and safety catheter ablation strategy. We hypothesized that, in patients with dual atrioventricular nodal physiology, during sinus rhythm (SR), high-density mapping (HDM) catheters could identify the SP signals, making possible to delineate small areas of slow conduction associated to abnormal electrograms on Koch's triangle. On a second step, radiofrequency (RF) applications safety guided by the HDM obtained with this method, should interrupt the circuit far from the His region. Finally, SP signals should disappear after the RF procedure when performing a new 3D HDM. A control group of patients without AVN dual physiology should show absence of fragmented/slow conduction zones.

Official Title
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High-density Activation Mapping of the Slow Pathway During Sinus Rhythm: a New and Simple Method to Guide Catheter Ablation in Patients With Typical Atrioventricular Nodal Reentrant Tachycardia

Conditions
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Supraventricular Tachycardia, Atrioventricular Nodal Re Entrant Tachycardia

Intervention / Treatment
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* Device: Description of Slow pathway signals to facilitate ablation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients > 18 yo with AVNRT observed after electrophysiological study Exclusion Criteria: Patients < 18 yo

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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
Intervention Model: Single Group Assignment
Interventional Model Description: Single group of intervention. A control group with absence of dual AVN phisiology to check lack of abnormal fragmented/slow conduction confluent zones.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Patients with atrioventricular node reentrant tachycardia<br>Patient with documented AVNRT and fragmented/slow conduction zones observed in a 3D high density mapping | Device: Description of Slow pathway signals to facilitate ablation<br>* 3D endocardial mapping in order to identify slow pathway signals and abolish or modificate them after radiofrequency ablation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Absence of reinduction of AVNRT after abolition of fragmented/slow conduction signals | Number of patients with absence of fragmented/slow conduction signals observed during sinus rhythm or atrial pacing after radiofrequency application | one day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Absence of AVNRT relapses | Number of patients with absence of relapses after 1 month of the electrophysiological study | one month | 
| Percentage of patient without AVNRT reinduction after procedure | Percentage of patients without tachycardia induction after radiofrequency applications protocol | One day |