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

Peri-Procedural Transmural Electrophysiological Imaging of Scar-Related Ventricular Tachycardia

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.

Study Overview

• Status: Recruiting
• Conditions: Myocardial Infarction; Ventricular Tachycardia
• Intervention / Treatment: Diagnostic test: EP Imaging and Testing

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.

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: John L Sapp, MD FRCPC; Phone Number: 902 473 4272; Email: john.sapp@nshealth.ca
• Study Contact Backup: Name: Karen A Giddens; Phone Number: 902 473 2758; Email: karen.giddens@nshealth.ca

Study Locations

• Canada
  • Nova Scotia
    • Halifax, Nova Scotia, Canada, B3H 3A7
      • Recruiting
      • QEII HSC
      • Contact: Karen A Giddens; Phone Number: 9024732758; Email: karen.giddens@nshealth.ca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

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).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: EP Imaging and Testing; MRI images,120 lead body surface mapping and NIPS testing will be completed to correlate areas of VT scar.

Diagnostic test: 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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Termination of Ventricular Tachycardia	The heart rhythm will be monitored continually with ECG electrodes to ascertain whether VT terminates with ablation.	Less than 10 minutes post ablation
VT recurrence rate	Any recurring VT occurring within 6 months post procedure	Less than 6 months post procedure

Collaborators and Investigators

• Sponsor: John Sapp
• Collaborators: Nova Scotia Health Authority; Rochester Institute of Technology
• Investigators: Principal Investigator: John L Sapp, MD FRCPC, Nova Scotia Health Authority

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2019
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): March 31, 2027

Study Registration Dates

• First Submitted: October 17, 2018
• First Submitted That Met QC Criteria: October 18, 2018
• First Posted (Actual): October 22, 2018

Study Record Updates

• Last Update Posted (Actual): March 17, 2026
• Last Update Submitted That Met QC Criteria: March 16, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiac Conduction System Disease; Vascular Diseases; Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arrhythmias, Cardiac; Infarction; Necrosis; Myocardial Ischemia; Ischemia; Tachycardia; Pathological Conditions, Signs and Symptoms; Myocardial Infarction; Tachycardia, Ventricular
• Other Study ID Numbers: SAPP006

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No