Imaging and Treatment Planning for Cardiac Radioablation (ITPCR)

Cardiac radioablation is a new treatment for ventricular tachycardia (VT), which uses beams of radiation to treat heart scar that causes VT. To identify the scar areas, magnetic resonance imaging (MRI) and computed tomography (CT) imaging are often used. These are both types of medical imaging that allow clinicians to examine scar area without having to do invasive surgery.

Researchers have developed new heart imaging protocols using both MRI and CT. Their MRI protocol method can now spot both dense and scattered scar tissue. The CT protocol combines multiple different types of scans into a single appointment and uses a special scanner that captures the motion of the heart. For this study, patients will undergo CT and MRI imaging according to these new imaging protocols.

With this study, researchers aim to show that these new imaging protocols can be undergone by patients with ventricular tachycardia and can be used to identify scar. Researchers will also use these scans to make radiation treatment plans to identify which types of treatment can be delivered safely to patients.

Study Overview

• Status: Not yet recruiting
• Conditions: Ischemia, Myocardial; Ventricular Tachycardia, Monomorphic; Ventricular Tachycardia (V-Tach)
• Intervention / Treatment: Diagnostic test: CT and MRI

• Study Type: Interventional
• Enrollment (Estimated): 15
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Stewart Gaede, PhD; Phone Number: 53144 519-685-8600; Email: stewart.gaede@lhsc.on.ca

Study Locations

• Canada
  • Ontario
    • London, Ontario, Canada
      • London Health Sciences Centre Research Inc
      • Contact: Stewart Gaede, PhD; Phone Number: 53144 5196858600; Email: stewart.gaede@lhsc.on.ca

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria

• Ischemic cardiomyopathy with monomorphic VT
• Referred by cardiologists
• 18 years of age or older Exclusion Criteria
• • Polymorphic ventricular tachycardia
• Ventricular fibrillation
• Pregnant or breastfeeding or planning to become pregnant or breastfeed during the study
• Estimated glomerular filtration rate ≤ 30 mL/min/1.73m2
• Previous allergic reaction to CT contrast agent Note that participants with contraindications for MRI can still be enrolled in this study but will not undergo MRI parts of this protocol.

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: CT and MRI; All participants will undergo both CT imaging and MRI imaging to identify areas of ischemic scar. Treatment plans will be created based on CT scans, using various treatment delivery and motion management techniques.	Diagnostic test: CT and MRI; All participants will undergo both CT imaging and MRI imaging to identify areas of ischemic scar. Treatment plans will be created based on CT scans, for all participants using various treatment delivery and motion management techniques.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Agreement among cardiologists for target regions, assessed by an inter- and intra-observer variability study using similarity metrics such as the Dice coefficient and Hausdorff distance.	Imaging protocols will be delivered to participants. Targets will be delineated by experts. Agreement between experts will be assessed..	6 months after conclusion of study
Adherence of treatment plans to dose constraints and deliverability of treatment plans.	Treatment plans will be created using various motion management and radiation treatment delivery strategies. Adherence of treatment plans to dose constraints will be assessed by comparing treatment plans to institutional dose constraints. Beam deliverability will be assessed by delivering the treatment plan to a static phantom and comparing the deposited dose to the expected dose. Treatment deliverability, as it relates to motion management, will be assessed by delivering the treatment plan to a moving phantom and comparing the deposited dose to the expected dose.	6 months after conclusion of study

Secondary Outcome Measures

Outcome Measure	Time Frame
Agreement between CT/MRI areas of interest (scar), assessed using similarity metrics such as the Dice coefficient and Hausdorff distance.	6 months after conclusion of study

Collaborators and Investigators

• Sponsor: Stewart Gaede
• Collaborators: Western University, Canada; St. Joseph's Health Care London; London Health Science Centre

Study record dates

Study Major Dates

• Study Start (Estimated): November 1, 2025
• Primary Completion (Estimated): July 1, 2026
• Study Completion (Estimated): September 1, 2026

Study Registration Dates

• First Submitted: April 7, 2025
• First Submitted That Met QC Criteria: April 14, 2025
• First Posted (Actual): April 22, 2025

Study Record Updates

• Last Update Posted (Estimated): September 26, 2025
• Last Update Submitted That Met QC Criteria: September 22, 2025
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Keywords: CT perfusion; Cardiac radioablation; Stereotactic arrhythmia radioablation; Ischemic fibrosis; Late iodine enhancement CT; Late gadolinium enhanced MRI
• Additional Relevant MeSH Terms: Cardiac Conduction System Disease; Vascular Diseases; Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arrhythmias, Cardiac; Tachycardia; Pathological Conditions, Signs and Symptoms; Myocardial Ischemia; Tachycardia, Ventricular; Diagnostic Techniques and Procedures; Diagnosis; Tomography; Diagnostic Imaging; Magnetic Resonance Imaging
• Other Study ID Numbers: 126882

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
• product manufactured in and exported from the U.S.: No