Cardiac ArrhythmiaSTART-CANCT04843683
StereoTactic Ablative RadioTherapy of Cardiac Arrhythmias
A study testing Stereotactic Ablative Radiotherapy in people with Cardiac Arrhythmia, run by University Health Network, Toronto at 1 site in Canada.
Trial summary
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… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Cardiac Arrhythmia
- What is being tested?
- Stereotactic Ablative Radiotherapy
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 60 participants
- Where
- 1 siteCanada
- Study dates
- 14 Dec 2021to Dec 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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.
Who cannot join
- 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.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Canada1 site, 1 recruiting
- Recruiting
Princess Margaret Cancer Center, University Health Network
Toronto, Ontario, M5G 2M9
Benjamin Lok, MD, 416-946-4501 ext. 5819, Benjamin.Lok@rmp.uhn.ca
About this study
Official title: 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.
- Conditions
- Cardiac Arrhythmia
- Being tested
- Stereotactic Ablative Radiotherapy
- Medical subject headings
- Arrhythmias, Cardiac
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Stereotactic Ablative RadiotherapyRadiation
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).
| Study group | Role | What they receive |
|---|---|---|
| Stereotactic ablative radiotherapy (SBRT) Arm | Experimental | 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). Receives: Radiation: Stereotactic Ablative Radiotherapy |
| Observational Arm | No intervention | 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 being measured
The primary outcome is the main question the study is designed to answer.
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.
Measured: 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.
Measured: Baseline to 18 months follow-up.
Secondary outcomes (6)
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).
Measured: 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).
Measured: 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.
Measured: Baseline to 6 months follow-up
Overall mortality record.
Safety will be evaluated by recording overall mortality at 6 month intervals post-treatment.
Measured: 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.
Measured: 1 month to 18 months follow-up.
Rates of hospital admissions.
Safety will be evaluated by recording rates of hospital admission during the study.
Measured: Baseline to 18 months follow-up.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 Apr 2021
- Study start14 Dec 2021
- Primary completionDec 2027 (estimated)
- Study completionDec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Cardiac ArrhythmiaStudies of the same condition, open and under way.
- More trials run by University Health Network, TorontoThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 60 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University Health Network, Toronto
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04843683
- Sponsor's protocol ID
- 20-6027
- Acronym
- START-CA
- Status last verified
- Mar 2026
- First submitted
- 1 Apr 2021
- Last updated
- 5 Mar 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 5 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- StereoTactic Ablative RadioTherapy of Cardiac Arrhythmias (START-CA): a Phase II Trial of Non-Invasive Treatment of Medically Refractory Patients
- ClinicalTrials.gov ID
- NCT04843683
- Acronym / sponsor ID
- START-CA / 20-6027
- Conditions
- Cardiac Arrhythmia
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 60 participants (estimated)
- Lead sponsor
- University Health Network, TorontoUniversity, hospital or other
- Study start
- 14 Dec 2021 (actual)
- Primary completion
- Dec 2027 (estimated)
- Study completion
- Dec 2027 (estimated)
- First posted
- 13 Apr 2021 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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 design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Stereotactic ablative radiotherapy (SBRT) Arm | Experimental | Radiation: Stereotactic Ablative RadiotherapyStereotactic 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). |
| Observational Arm | No intervention | –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. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- 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.
Key exclusion criteria (1 listed)
- 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.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Stereotactic Ablative RadiotherapyStereotactic 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 (SBRT) Arm |
Primary outcome
Change from Baseline in ICD therapies.
Time frame: Baseline to 18 months follow-up.
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.
Change from Baseline in the number or dose of antiarrhythmic medications.
Time frame: Baseline to 18 months follow-up.
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.
6 secondary outcomes
Measure patient quality-of-life during the study.
Time frame: Baseline to 18 months follow-up.
Measure patient quality-of-life during the study.
Time frame: Baseline to 18 months follow-up.
Measure patient subjective distress following treatment.
Time frame: Baseline to 6 months follow-up
Overall mortality record.
Time frame: 6 to 18 months follow-up.
Number of patients with acute and long-term toxicity as assessed by CTCAE v5.0.
Time frame: 1 month to 18 months follow-up.
Rates of hospital admissions.
Time frame: Baseline to 18 months follow-up.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 Mar 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Stereotactic Ablative Radiotherapy in people with Cardiac Arrhythmia, run by University Health Network, Toronto at 1 site in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 5 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Benjamin Lok, MD (416-946-2919, benjamin.lok@rmp.uhn.ca), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change from Baseline in ICD therapies. (time frame: Baseline to 18 months follow-up.). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Mar 2026.