Does Timing of VT Ablation Affect Prognosis in Patients With an Implantable Cardioverter-defibrillator?

Study Overview
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Brief Summary
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The purpose of this study is to assess whether the burden of untreated non-sustained ventricular tachycardias (VTs), or episodes treated with anti-tachycardia pacing, correlates with appropriate implantable cardiac defibrillator (ICD) shock therapies and to evaluate if the timing of radiofrequency VT ablation affects the prognosis of ICD recipients.

Detailed Description
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Enrolled patients will remain in a first phase of the study until the first appropriate ICD shock will be delivered. The objective of this first stage is to assess whether the burden of untreated non sustained VTs or episodes treated with anti-tachycardia pacing is predictive of appropriate ICD shocks. The second phase of the study will start after the first appropriate ICD shock delivered for VT. Patients will be then randomized to immediate VT ablation or to standard treatment, meaning waiting until next arrhythmic storm to perform a VT ablation procedure. The objective of this phase is compare the rate of worsening heart failure hospitalizations and deaths from any cause between the two groups.

Conditions
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Ventricular Tachycardias

Intervention / Treatment
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* Procedure: Immediate radiofrequency ablation of ventricular tachycardia
* Procedure: Radiofrequency ablation of ventricular tachycardia


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients already implanted with ICD (single-/dual -chamber, with or without cardiac resynchronization therapy) for primary or secondary prevention of sudden cardiac death Exclusion Criteria: Phase A exclusion Criteria: General contraindication to transcatheter ablation Contraindication to antithrombotic therapy Patients chronically treated with class I and III antiarrhythmic drugs Phase B exclusion criteria: Patients developing first occurrence of incessant VTs Patients receiving a shock for first occurrence of clinically verified ventricular fibrillation Patients with aetiology differing from ischemic heart disease for coronary artery disease and from non-ischemic dilatative cardiomyopathy

Ages Eligible for Study
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Minimum Age: 18 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Group A<br>Patients will be randomized to a VT ablation procedure immediately after an appropriate ICD shock | Procedure: Immediate radiofrequency ablation of ventricular tachycardia<br>* Radiofrequency ablation of ventricular tachycardia is performed immediately after an appropriate ICD shock<br>|
| Active Comparator: Group B<br>Patients will wait until an arrhythmic storm to undergo a VT ablation procedure | Procedure: Radiofrequency ablation of ventricular tachycardia<br>* Radiofrequency ablation of ventricular tachycardia will be performed after an arrhythmic storm occurs<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurrence of the first appropriate ICD shock during phase A |  | Event Driven | 
| Number of patients showing worsening heart failure hospitalizations or deaths from any cause during phase B |  | Two Years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of patients showing cardiac deaths during phase B |  | Two Years | 
| Number of patients showing electrical storm (ES) recurrences during phase B |  | Two Years | 
| Number of patients showing VT recurrences during phase B |  | Two Years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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ICD shocks, Ventricular tachycardias ablation, Timing of ablation, Electrical storm, Arrhythmic storm