Peri-Procedural Transmural Electrophysiological (EP) Imaging of Scar-Related Ventricular Tachycardia

NCT ID: NCT03713866

Last Updated: 2024-08-20

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 20 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2019-11-01
• Study Completion Date: 2027-03-31

Brief Summary

Ventricular tachycardia (VT) contributes to over 350,000 sudden deaths each year in the US. Malignant VTs involve an electrical "short circuit" in the heart, formed by narrow channels of surviving tissue inside myocardial scar. An important treatment is to use catheter ablation to "block" the channel that forms the circuit. Effective ablation requires imaging guidance to visualize the VT circuit relative to scar structures in 3D. Unfortunately, with conventional catheter mapping, up to 90% of the VT circuits are too short-lived to be mapped. For the 10% "mappable" VTs, their data are only available during ablation and limited to one ventricular surface. This inadequacy of functional VT data largely limits the knowledge about scar-related VT and ablation strategies, and reduces the ability of clinicians to identify ablation targets and assess ablation outcome.

The central hypothesis of this proposal is that functional VT data, integrated with CT or MRI scar data in 3D, can improve VT ablation efficacy with pre-procedural identification of ablation targets and post-procedural mechanistic elucidation of ablation failure. This research builds on the rapidly increasing clinical interest in electrocardiographic imaging (ECGi), an emerging technique that obtains cardiac electrical activity through inverse reconstructions from ECGs. The specific objective is to push the boundary of ECGi to provide - as a conjunction to intra-procedural catheter mapping - pre-ablation and post-ablation imaging of functional VT circuits integrated with 3D scar structure.

Detailed Description

Electrocardiographic imaging (ECGi) is an emerging technique to image cardiac electrical activity through inverse reconstructions from body-surface ECGs. After 40 years of active research, the potential of ECGi as a noninvasive adjunct to catheter mapping is gaining rapid attention in the clinical community.

A total of 40 consecutive post-infarction VT patients will be prospectively enrolled and recruited from those who have been referred for catheter ablation of scar-related VT. Within 7 days before the ablation procedure, these patients will undergo noninvasive cardiac CT or MRI imaging and noninvasive programmed stimulation (NIPS) study with simultaneous 120-lead body- surface ECG mapping (pre-ablation NIPS). MRI will be performed for patients with implantable defibrillators for whom it is considered safe to do so. CT imaging will be performed for those with Implantable Cardioverter Defibrillators (ICDs) which are not MRI compatible.

At the time of scheduled ablation, all patients will undergo standard catheter mapping and ablation procedure as a part of standard care. Within 7 days after the ablation procedure, the patients will undergo cardiac MRI imaging and noninvasive programmed stimulation (NIPS) with simultaneous 120-lead body-surface ECG mapping (post-ablation NIPS). For patients who cannot undergo MRI, CT imaging will not be repeated.

At 6 months after the procedure, a follow-up will occur as a part of standard care where outcome data regarding the chronic success of the ablation procedure will be collected and ICD interrogation will be performed. No imaging or mapping is planned at the follow-up.

Conditions

Ventricular Tachycardia; Myocardial Infarction

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: DIAGNOSTIC
• Blinding Strategy: NONE

Study Groups

EP Imaging and Testing

MRI images,120 lead body surface mapping and NIPS testing will be completed to correlate areas of VT scar.

Group Type: EXPERIMENTAL

EP Imaging and Testing

Intervention Type: DIAGNOSTIC_TEST

Magnetic Resonance Imaging: pre-procedure imaging is standard care prior to catheter ablation procedures for VT to document anatomy of the heart.

120-Lead Body Surface Mapping: a 120-lead ECG will be recorded using a standardized mapping protocol. 120 disposable radiolucent silver chloride (Ag/AgCl) surface electrodes will be placed on the torso in 18 strips and connected via cables to an advanced acquisition system.

Noninvasive programmed stimulation (NIPS) study will be performed using the patient's implanted defibrillator, and is part of standard practice during a VT catheter ablation.

Interventions

EP Imaging and Testing

Magnetic Resonance Imaging: pre-procedure imaging is standard care prior to catheter ablation procedures for VT to document anatomy of the heart.

120-Lead Body Surface Mapping: a 120-lead ECG will be recorded using a standardized mapping protocol. 120 disposable radiolucent silver chloride (Ag/AgCl) surface electrodes will be placed on the torso in 18 strips and connected via cables to an advanced acquisition system.

Noninvasive programmed stimulation (NIPS) study will be performed using the patient's implanted defibrillator, and is part of standard practice during a VT catheter ablation.

Intervention Type: DIAGNOSTIC_TEST

Eligibility Criteria

Inclusion Criteria

• One or more episodes of sustained monomorphic VT
• Referred for catheter ablation
• Previously implanted ICD
• Signed the patient informed consent form
• Able and willing to comply with all pre-, post-, and follow-up testing and requirements

Exclusion Criteria

• Have estimated Glomerular Filtration Ratio (eGFR) less than 30
• Have a life expectancy less than 6 months or are listed for heart transplantation at time of inclusion
• Are pregnant
• Are on IV inotropic agents
• Have any contraindication to catheter ablation (including but not limited to mechanical prosthetic aortic and mitral valves, known protruding Left Ventricular (LV) thrombus
• New York Heart Association (NYHA) functional class IV
• Had ST wave elevation myocardial infarction within < 1 month
• Unwilling or unable to undergo cardiac MRI scan AND unwilling or unable to undergo cardiac CT scan (e.g. contrast allergy).

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 85 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Nova Scotia Health Authority

OTHER

Sponsor Role: collaborator

Rochester Institute of Technology

OTHER

Sponsor Role: collaborator

John Sapp

OTHER

Sponsor Role: lead

Responsible Party

John Sapp

Staff Cardiologist

Responsibility Role: SPONSOR_INVESTIGATOR

Principal Investigators

John L Sapp, MD FRCPC

Role: PRINCIPAL_INVESTIGATOR

Nova Scotia Health Authority

Locations

QEII HSC

Halifax, Nova Scotia, Canada

Site Status: RECRUITING

Countries

Canada

Central Contacts

John L Sapp, MD FRCPC

Role: CONTACT

john.sapp@nshealth.ca

902 473 4272

Karen A Giddens

Role: CONTACT

karen.giddens@nshealth.ca

902 473 2758

Facility Contacts

Karen A Giddens

Role: primary

karen.giddens@nshealth.ca

9024732758

Other Identifiers

SAPP006

Identifier Type: -

Identifier Source: org_study_id