Better Mechanistic Understanding of and Risk Stratification for Ventricular Tachyarrhythmias Through ECGI

Study Overview
=================
Brief Summary
-----------------
This study aims to evaluate the electrophysiological properties of the heart conduction system in patients with (increased risk of) ventricular tachyarrhythmias (VTA) and sudden cardiac arrest, and in a control cohort. The electrophysiological properties will be measured with the relatively new technique ECG-Imaging (ECGI). Moreover, clinical data of subjects will be gathered. By combining the data from the data gathering and the results of ECGI, the investigators hope to increase mechanistic understanding of and risk stratification for VTAs. The investigators aim to be able to identify patients at risk of an arrhythmic event, and aim for better treatment strategies in the future.

Detailed Description
-----------------
ECGI combines electrical body-surface mapping with 256 electrodes placed on the thorax with a CT-scan obtaining the anatomy of the heart and torso, hereby able to reconstruct local electrograms, activation and recovery times. In recent research, ECGI provided numerous extra insights into normal cardiac electrophysiology, but also electrophysiological disorders and disease. The results strongly suggest that ECGI can play a pivotal role in further characterizing arrhythmia mechanisms, therefore could do so for VTAs, leading to diagnosis and treatment improvement. Moreover, ECGI seems to have the potential to detect arrhythmogenic substrate in individuals before their first event, offering the possibility to diagnose and treat patients before sudden cardiac arrest occurs. In the BREACH-ECGI study: ECGI will be used to noninvasively characterize the epicardial electrophysiological substrate and triggers of: Patients with (increased risk of) VTAs A control cohort. Results will be evaluated for increased mechanistic understanding and risk stratification. Moreover, clinical data of subjects will be gathered. These data will be analyzed to determine their prognostic value in terms of arrhythmia risk

Official Title
-----------------
Better Mechanistic Understanding of and Risk Stratification for Ventricular Tachyarrhythmias Through ECGI

Conditions
-----------------
Heart Arrest, Ventricular Tachycardia, Ventricular Arrythmia, Ventricular Fibrillation, Polymorphic Ventricular Tachycardia, Sudden Cardiac Death, Sudden Cardiac Arrest, Sudden Cardiac Death Due to Cardiac Arrhythmia, Cardiac Death, Cardiac Arrest, Cardiac Arrhythmia, Congenital Heart Disease

Intervention / Treatment
-----------------
* Diagnostic Test: ECG-Imaging


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: In order to be eligible to participate in this study, a subject must be ≥ 18 years old, have either a history of VTAs or be at risk of VTAs and have one of the following diagnoses: Ischemic cardiomyopathy Non-ischemic cardiomyopathy Non-structural heart disease Congenital heart disease (with a limitation to CCTGA and situs inversus) Or: a subject must be ≥ 18 years old and have a structurally normal heart with a clinical indication for a cardiac CT. Exclusion Criteria: A potential subject who meets any of the following criteria will be excluded from participation in this study: A known strong reaction against electrode attachment or contrast agent. Any serious medical condition, which in the opinion of the investigator, may adversely affect the safety and/or effectiveness of the participant or the study. Pregnancy, nursing or planning to be pregnant. The subject has an estimated glomerular filtration rate (eGFR) of <30mL/min/1.73m2, using the MDRD calculation 14. Being unable to give informed consent.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Both groups (control and diseased) will undergo a body surface potential mapping and a cardiac + low dose CT-scan.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Control<br>Control subjects receiving body-surface potential mapping (BSPM) and either a CT-scan or a CMR scan | Diagnostic Test: ECG-Imaging<br>* A body surface potential mapping and a cardiac + low dose CT-scan<br>|
| Experimental: Diseased<br>Diseased subjects receiving body-surface potential mapping (BSPM) and either a CT-scan or a CMR scan. Outcome measures from these procedures will be compared to controls. | Diagnostic Test: ECG-Imaging<br>* A body surface potential mapping and a cardiac + low dose CT-scan<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ECG-Imaging outcome: epicardial potentials | reconstructed epicardial potentials, represented in mV over time(s). | 3 years | 
| ECG-Imaging outcome: activation and repolarization maps | Activation and repolarization maps. Acivation and repolarization times are determined from the epicardial potentials, expressed in ms. These are shown on a CT-derived or CMR-derived heart mesh. The entire activation and repolarization of the epicardium of the heart can be visualized this way. | 3 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| (Possible) Prognostic risk factors for recurrent ventricular arrhythmias | Possible risk factors, found in the clinical data collection, expressed as odds/hazard ratio. | 6 years | 
| Recurrence of ventricular arrhythmias | Documentation over the period of follow-up, if subjects had a recurrence of ventricular arrythmia(s), presented as number of events over a time period. | 6 years |