## Protocol Section
### Identification Module
**NCT ID:** NCT06425822

**Acronym:** CLASS-VA

**Brief Title:** Characterization of Left Atrial Substrate in Patients With Ventricular Arrhythmias

**Official Title:** Characterization of Left Atrial Substrate in Patients With Ventricular Arrhythmias

#### Organization Study ID Info
**ID:** EC-2023-281
#### Organization
**Class:** OTHER
**Full Name:** Universitair Ziekenhuis Brussel
### Status Module
#### Completion Date
**Date:** 2027-10-31

**Type:** ESTIMATED

#### Expanded Access Info
#### Last Update Post Date
**Date:** 2024-05-22

**Type:** ACTUAL

**Last Update Submit Date:** 2024-05-21

**Overall Status:** RECRUITING

#### Primary Completion Date
**Date:** 2025-10-31

**Type:** ESTIMATED

#### Start Date
**Date:** 2023-11-08

**Type:** ACTUAL

**Status Verified Date:** 2024-05

#### Study First Post Date
**Date:** 2024-05-22
**Type:** ACTUAL
**Study First Submit Date:** 2024-05-09
**Study First Submit QC Date:** 2024-05-21
### Sponsor Collaborators Module

#### Lead Sponsor

**Class:** OTHER

**Name:** Universitair Ziekenhuis Brussel

#### Responsible Party

**Investigator Affiliation:** Universitair Ziekenhuis Brussel

**Investigator Full Name:** Andrea Sarkozy

**Investigator Title:** Clinical Professor

**Type:** PRINCIPAL_INVESTIGATOR

### Oversight Module

**Is FDA Regulated Device:** False

**Is FDA Regulated Drug:** False

### Description Module

**Brief Summary:** The goal of this observational study is to analyze the characteristics of left atrial electroanatomical maps in patients without a history of atrial fibrillation but with a high clinical risk of developing it, as indicated by the presence of structural heart disease or a CHA2DS2-VASc score ≥ 2 points. The study cohort will be compared to a historical cohort of patients with diagnosed atrial fibrillation in a propensity-matched fashion.

The main questions it aims to answer are:

* Are the left atrial electroanatomical changes a consequence or a precursor to the development of atrial fibrillation?
* Are the left atrial electroanatomical findings different between patients with atrial fibrillation and those at high risk of developing it?
* What is the prognostic impact of left atrial pathologic changes in patients without diagnosed atrial fibrillation in terms of cardiovascular outcomes?

### Conditions Module

**Conditions:**

- Atrial Remodeling

### Design Module

#### Design Info

**Observational Model:** COHORT

**Time Perspective:** PROSPECTIVE

#### Enrollment Info

**Count:** 50

**Type:** ESTIMATED

**Study Type:** OBSERVATIONAL

### Arms Interventions Module

#### Arm Group 1

**Description:** Inclusion criteria:

* Age ≥ 18 years old.
* Absence of a prior history of atrial fibrillation or flutter.
* Patients presenting for ablation of any ventricular tachycardia related to structural heart disease or any ventricular arrhythmia with a CHA2DS2-VASc score ≥ 2.

Exclusion criteria:

* Presence of thrombus in the left atrial appendage.
* Complications related to the index procedure.
* Insufficient quality of the left atrial electroanatomical map.

**Intervention Names:**

- Diagnostic Test: Left atrial electroanatomical mapping

**Label:** Left atrial mapping group in patients without atrial fibrillation

### Interventions

#### Intervention 1

**Arm Group Labels:**

- Left atrial mapping group in patients without atrial fibrillation

**Description:** Left atrial electroanatomical mapping (substrate and functional mapping)

**Name:** Left atrial electroanatomical mapping

**Type:** DIAGNOSTIC_TEST

### Outcomes Module

#### Other Outcomes

**Description:** Episodes diagnosed via a single-lead ECG tracing or a complete 12-lead ECG lasting at least 30 seconds, or AHRE episodes detected by any cardiac implantable electronic device (CIED), lasting at least 5 minutes.

**Measure:** Incidence of atrial fibrillation during follow-up.

**Time Frame:** 12 months

**Description:** Only type 1 myocardial infarctions, those related to acute coronary obstruction, will be considered.

**Measure:** Incidence of myocardial infarction during follow-up

**Time Frame:** 12 months

**Description:** Stroke will be defined as any objective evidence of permanent brain, spinal cord, or retinal cell death resulting from a vascular cause, substantiated by pathological or imaging evidence, with or without accompanying clinical symptoms.

**Measure:** Incidence of stroke during follow-up

**Time Frame:** 12 months

**Description:** Transient ischemic attack will be defined as a sudden, focal neurological deficit of presumed vascular origin lasting less than 24 hours.

**Measure:** Incidence of transient ischemic attack incidence during follow-up

**Time Frame:** 12 months

#### Primary Outcomes

**Description:** Substrate characterization will involve measuring Low Voltage (LV) and Transition Voltage (TV) Zones (LV zone voltage cut-off of \<0.5mV; TV zone voltage limits within 0.5 and 1mV). These zones will be considered if they encompass an area of at least 1cm², containing ≥3 neighboring points within ≤10mm distance. The total LVZ and TVZ surfaces will be expressed as a percentage relative to the total surface area of the left atrium (excluding the pulmonary veins and the mitral annulus).

A comparative analysis of substrate characteristics will be conducted between two groups: the study group (comprising patients without atrial fibrillation but at risk of developing it) and the control group (a historical cohort of patients with known atrial fibrillation).

**Measure:** Substrate characterization of the left atrium.

**Time Frame:** 18 months

**Description:** Functional analysis will rely on identifying deceleration zones characterized by isochronal crowding, defined as having ≥3 isochrones within a 1cm radius, using an 8-color scale of left atrial isochronal activation mapping.

A comparative analysis of functional characteristics will be conducted between two groups: the study group (comprising patients without atrial fibrillation but at risk of developing it) and the control group (a historical cohort of patients with known atrial fibrillation).

**Measure:** Functional characterization of the left atrium.

**Time Frame:** 18 months

### Eligibility Module

**Eligibility Criteria:** Inclusion Criteria:

* Absence of a prior history of atrial fibrillation or flutter.
* Patients presenting for ablation of any ventricular tachycardia related to structural heart disease or any ventricular arrhythmia with a CHA2DS2-VASc score ≥ 2.

Exclusion criteria:

* Presence of thrombus in the left atrial appendage.
* Complications related to the index procedure.
* Insufficient quality of the left atrial electroanatomical map.

**Minimum Age:** 18 Years

**Sampling Method:** NON_PROBABILITY_SAMPLE

**Sex:** ALL

**Standard Ages:**

- ADULT

- OLDER_ADULT

**Study Population:** Consecutive patients undergoing ventricular arrhythmias ablations in whom transeptal access is needed for the ablation of the targeted arrhythmia.

### Contacts Locations Module

#### Central Contacts

**Contact 1:**

**Email:** Andrea.Sarkozy@uzbrussel.be

**Name:** Andrea Sarkozy, MD, PhD

**Phone:** 0032 02476 3657

**Role:** CONTACT

#### Locations

**Location 1:**

**City:** Jette

**Contacts:**

***Contact 1:***

- **Email:** Andrea.Sarkozy@uzbrussel.be

- **Name:** Andrea Sarkozy, MD, PhD

- **Phone:** 0032 02476 3657

- **Role:** CONTACT

**Country:** Belgium

**Facility:** Universitair Ziekenhuis Brussel

**State:** Brussels

**Status:** RECRUITING

**Zip:** 1090

#### Overall Officials

**Official 1:**

**Affiliation:** Universitair Ziekenhuis Brussel

**Name:** Andrea Sarkozy, MD, PhD

**Role:** PRINCIPAL_INVESTIGATOR

### IPD Sharing Statement Module

**IPD Sharing:** UNDECIDED

## Derived Section

### Condition Browse Module - Ancestors

- ID: D000010335

- Term: Pathologic Processes

- ID: D000020763

- Term: Pathological Conditions, Anatomical

### Condition Browse Module - Browse Branches

- Abbrev: BC14

- Name: Heart and Blood Diseases

- Abbrev: BC23

- Name: Symptoms and General Pathology

- Abbrev: All

- Name: All Conditions

### Condition Browse Module - Browse Leaves

- ID: M4453

- Name: Arrhythmias, Cardiac

- Relevance: LOW

- As Found: Unknown

- ID: M30384

- Name: Atrial Remodeling

- Relevance: HIGH

- As Found: Atrial Remodeling

- ID: M22519

- Name: Pathological Conditions, Anatomical

- Relevance: LOW

- As Found: Unknown

### Condition Browse Module - Meshes

- ID: D000064752

- Term: Atrial Remodeling

### Misc Info Module

- Version Holder: 2024-05-31
