StereoTactic Ablative RadioTherapy of Cardiac Arrhythmias (START-CA)

StereoTactic Ablative RadioTherapy of Cardiac Arrhythmias (START-CA): a Phase II Trial of Non-Invasive Treatment of Medically Refractory Patients

This is a prospective, single-center, phase II trial that will be monitoring the safety and efficacy of using stereotactic ablative radiotherapy (SBRT) to treat patients with a medical condition affecting heart rate and rhythm (refractory arrhythmias) within the University Health Network (Princess Margaret Cancer Centre and Toronto General Hospital). The primary objective will be to prospectively monitor patient cardiac outcomes following SBRT.

Study Overview

• Status: Recruiting
• Conditions: Cardiac Arrhythmia
• Intervention / Treatment: Radiation: Stereotactic Ablative Radiotherapy

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Benjamin Lok, MD; Phone Number: 416-946-2919; Email: benjamin.lok@rmp.uhn.ca

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5G 2M9
      • Recruiting
      • Princess Margaret Cancer Center, University Health Network
      • Contact: Benjamin Lok, MD; Phone Number: 5819 416-946-4501; Email: Benjamin.Lok@rmp.uhn.ca

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Patients with heart rate and rhythm condition (arrhythmia) who have failed standard of care treatment with medication OR at least one prior invasive catheter ablation procedure.
• Patients deemed medically fit to receive stereotactic ablative radiotherapy as determined by their Radiation Oncologist.

Exclusion Criteria:

• Patients who have previously received high dose radiotherapy to the target area and cannot safely receive further treatment OR are unable to receive radiotherapy due to other contraindications.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Stereotactic ablative radiotherapy (SBRT) Arm; Stereotactic ablative radiotherapy (SBRT) is a type of radiation treatment that delivers precise, high dose radiation to targeted areas. In this study, a single treatment of SBRT will be delivered to the abnormal area of a participant's heart that is causing dangerous heart rate and rhythm changes (arrhythmia).	Radiation: Stereotactic Ablative Radiotherapy; Stereotactic ablative radiotherapy (SBRT) is a type of radiation treatment that delivers precise, high dose radiation to targeted areas. In this study, a single treatment of SBRT will be delivered to the abnormal area of a participant's heart that is causing dangerous heart rate and rhythm changes (arrhythmia).
No Intervention: Observational Arm; Potential participants who are eligible to be included in the study, but who choose not to have the SBRT procedure, can still receive standard medical treatment alone and be followed up with study visits and questionnaires.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from Baseline in ICD therapies.	Patient cardiac outcomes will be evaluated by changes from baseline in ICD (Implantable Cardioverter-Defibrillator) therapies (ICD shock frequency) following radiotherapy at 1, 3, 6, 12 and 18 months of follow-up.	Baseline to 18 months follow-up.
Change from Baseline in the number or dose of antiarrhythmic medications.	Patient cardiac outcomes will be evaluated by changes from baseline in the number or dose of antiarrhythmic medications following radiotherapy at 1, 3, 6, 12 and 18 months of follow-up.	Baseline to 18 months follow-up.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Measure patient quality-of-life during the study.	Patient-Reported Health Related Quality of Life (HRQOL) will be assessed at each 1, 3, 6, 12 and 18 month follow-up, using the following assessment questionnaires: 36-item Short Form Health Survey (SF-36).	Baseline to 18 months follow-up.
Measure patient quality-of-life during the study.	Patient-Reported Health Related Quality of Life (HRQOL) will be assessed at each 1, 3, 6, 12 and 18 month follow-up, using the following assessment questionnaire: the Hospital Anxiety and Depression Scale (HADS-A). A lower score indicates a better outcome. HADS-A Scoring: 0-7 = Normal, 8-10 = Borderline abnormal (borderline case), 11-21 = Abnormal (case).	Baseline to 18 months follow-up.
Measure patient subjective distress following treatment.	Patient subjective distress following treatment will be measured at baseline, and 1 month and 6-months follow-up, using the Impact of Events Scale (IES-R). A higher score indicates a worse outcome. IES-R Scoring: 24 or more = Post-traumatic stress disorder (PTSD) is a clinical concern. 33 and above = This represents the best cutoff for a probable diagnosis of PTSD. 37 or more = This is high enough to suppress immune system's functioning.	Baseline to 6 months follow-up
Overall mortality record.	Safety will be evaluated by recording overall mortality at 6 month intervals post-treatment.	6 to 18 months follow-up.
Number of patients with acute and long-term toxicity as assessed by CTCAE v5.0.	Acute (less than or equal to 90 days) and long-term (greater than 90 days) toxicity will be evaluated by using prospective follow-up and grading according to the latest version of the Common Terminology Criteria for Adverse Events (CTCAE) v5.0.	1 month to 18 months follow-up.
Rates of hospital admissions.	Safety will be evaluated by recording rates of hospital admission during the study.	Baseline to 18 months follow-up.

Collaborators and Investigators

• Sponsor: University Health Network, Toronto

Study record dates

Study Major Dates

• Study Start (Actual): December 14, 2021
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2027

Study Registration Dates

• First Submitted: April 1, 2021
• First Submitted That Met QC Criteria: April 11, 2021
• First Posted (Actual): April 13, 2021

Study Record Updates

• Last Update Posted (Actual): March 5, 2026
• Last Update Submitted That Met QC Criteria: March 3, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Pathological Conditions, Signs and Symptoms; Arrhythmias, Cardiac
• Other Study ID Numbers: 20-6027

Drug and device information, study documents

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