Utility of ICD Electrograms During Ventricular Tachycardia Ablation

Study Overview
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Brief Summary
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With the increasing use of implantable cardioverter defibrillators (ICD) for primary prevention in patients with structural heart disease, an increasing number of patients are expected to develop their first episode of monomorphic ventricular tachycardia (VT) after an ICD is in place and the only documentation of the clinical arrhythmia will be the ICD electrogram (EG). The absence of a 12-lead ECG in patients with an ICD and sustained monomorphic VT represents a limitation when performing treatment with radiofrequency (RF) ablation. The analysis of ICD-EG during a RF ablation procedure is expected to provide a reference model of VT with clinical expression consisting of the electrical signal of the ICD during VT (which otherwise is not generally possible to obtain in ICD patients). This will allow for a more targeted approach to the substrate of the VT with clinical expression because: 1) if VT is induced by programmed stimulation, one can tell whether it is with clinical expression or not, and 2) if VT is not induced, ventricular pacing could be performed based on the comparative analysis of morphology and activation times of ICD-EG. These approaches will result in improved outcomes of the ablation procedure.

Official Title
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Aid of Recording ICD Electrograms During Monomorphic Ventricular Tachycardia Ablation Procedures

Conditions
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Sustained Monomorphic Ventricular Tachycardia

Intervention / Treatment
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* Procedure: Conventional RF catheter ablation
* Procedure: Investigational RF Catheter Ablation using ICD-EG information


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 years or older Clinical indication for RF catheter ablation Presence of an implanted ICD At least 1 episode of spontaneous sustained monomorphic VT documented with ICD electrogram Presence of structural heart disease Able to obtain signed informed consent and willing to comply with study activity requirements Exclusion Criteria: It is anticipated that data can not be obtained during follow-up Unwilling or unable to provide informed consent Women who are or may potentially be pregnant Patients who are participating in another clinical trial

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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Conventional RF catheter ablation<br>Conventional RF ablation will be performed without using ICD-EG information | Procedure: Conventional RF catheter ablation<br>* RF catheter ablation will be performed as usually done by each center. No ICD EGMs will be obtained and used during the ablation procedure (do not place the programming head over the ICD generator).<br>|
| Other: Investigational RF Catheter Ablation using ICD-EG information<br>RF Catheter Ablation will be performed using ICD-EG information | Procedure: Investigational RF Catheter Ablation using ICD-EG information<br>* RF ablation procedure will be performed with the programming head over the ICD generator. ICD EGMs will be registered every time VT is induced and during ventricular pacing. ICD EGMs obtained during ablation procedure will be compared with the EGMs of the registered spontaneus VT and used to locate appropriate ablation sites.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of patients free of VT recurrence |  | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reduction in number of VT recurrence |  | 6 months | 
| Reduction in the proportion of patients free of VT recurrence |  | 6 months | 
| Reduction in the proportion of patients free of recurrence in patients in whom 12-lead ECG of the spontaneous VT is not available and in those in whom hemodinamically tolerated VT is not induced |  | 6 months and total follow-up | 
| Improvement of spatial resolution of the ICD-EG after information from local ventricular endocardial acceleration is added | This outcome will be studied from the stored signal together with the ICD-EG on the device in the subgroup of patients with a device that allows to obtain this parameter. In the remaining patients, signals will be obtained noninvasively with a seismocardiogram using a highly sensitive accelerometer located in the sternal midline of the xiphoid process and simultaneously synchronized with the ECG. | 6 months |