Ablation Targets of Scar-related Ventricular Tachycardia Identified by Dynamic Functional Substrate Mapping

Study Overview
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Brief Summary
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This study aims at comparing the recurrence rates of ventricular tachycardia ablated after being mapped by 2 different techniques.

Detailed Description
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The study participants are patients presented with recurrent ventricular tachycardia. They will be divided into 2 groups in terms of mapping. The first group will use mapping during sinus rhythm to identify late potentials that may be incriminated in the tachycardia circuit. The other group will undergo mapping during right ventricular extrastimulus pacing to unmask hidden potentials. The identified potentials will be ablated in both groups.

Official Title
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Ablation Targets of Scar-related Ventricular Tachycardia Identified by Dynamic Functional Substrate Mapping

Conditions
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Tachycardia, Ventricular

Intervention / Treatment
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* Procedure: Radiofrequency ablation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: • Patients with structural heart disease; previous myocardial infarction, left ventricular dilatation/systolic dysfunction, or normal left ventricular diameters/ systolic function with evidence of ventricular scar on contrast enhanced-cardiac magnetic resonance or electroanatomic map. Sustained monomorphic ventricular tachycardia documented by 12-lead ECG or implantable cardioverter defibrillator (electrograms resistant to antiarrhythmic drug treatment or requiring implantable cardioverter defibrillator therapies. Exclusion Criteria: • Patients with ventricular arrhythmias attributed to reversible causes.
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 |
| --- | --- |
| Active Comparator: Sinus Rhythm<br>This group will undergo mapping during sinus rhythm to identify and ablate late potentials that may be incriminated in the tachycardia circuit. | Procedure: Radiofrequency ablation<br>* Both groups will undergo radiofrequency ablation of potentials likely responsible for the tachycardia. Those potentials are identified by the formentioned 2 distinct methods.<br>|
| Active Comparator: Right ventricular extrastimulus pacing group<br>This group will undergo mapping during right ventricular single extrastimulus pacing to identify and thus ablate potentials that might have been masked during sinus rhythm. | Procedure: Radiofrequency ablation<br>* Both groups will undergo radiofrequency ablation of potentials likely responsible for the tachycardia. Those potentials are identified by the formentioned 2 distinct methods.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of participants with recurrence of ventricular tachycardia | Recurrence of ventricular tachycardia implies receiving at least one appropriate implantable cardioverter defibrillator therapy or hospital admission due to symptomatic ventricular tachycardia. | 12 months | 
| Number of participants receiving at least one appropriate implantable cardioverter defibrillator therapy | Appropriate therapies include anti tachycardia pacing and shocks | 12 months | 
| Time to first recurrence of ventricular tachycardia | This will be measured from the end of the ablation procedure till the first documented recurrence of ventricular tachycardia whether by electrocardiogram or by device tracings | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of participants who experience sudden cardiac death | This is defined as unexpected death where a cardiac cause is the most probable etiology | 12 months | 
| Number of participants who die from any cause (All-cause mortality) | This includes death from any cause | 12 months | 
| Number of hospitalizations for heart failure per participant | This denotes hospital admission due to new or worsening symptoms of heart failure | 12 months |