Ventricular TachycardiaNCT04162171
Cohort Study - SBRT for VT Radioablation
A study testing Stereotactic Body Radiotherapy (SBRT) ablation of VT in people with Ventricular Tachycardia and Myocardial Infarction, run by John Sapp at 1 site in Canada.
Trial 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. Read more about this study
- Who is it for?
- Any age
- Conditions the study is for
- Ventricular Tachycardia, Myocardial Infarction, Heart Disease Structural Disorder
- What is being tested?
- Stereotactic Body Radiotherapy (SBRT) ablation of VT
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 12 participants
- Where
- 1 siteCanada
- Study dates
- 1 Jun 2021to 1 Sep 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 Any age
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Who may be able to join
- Structural heart disease: ischemic or non-ischemic cardiomyopathy diagnosed with cardiac imaging demonstrating either segmental myocardial dysfunction, or presence of scar, AND
- One of the following monomorphic VT events despite prior attempted catheter ablation (or contraindication for ablation), AND despite treatment with a class III antiarrhythmic drug (contraindicated, ineffective or not tolerated): A: Documented sustained monomorphic VT terminated by pharmacologic means, DC cardioversion or manual ICD Therapy. B: ≥3 episodes of monomorphic VT treated with antitachycardia pacing (ATP), at least one of which was symptomatic C: ≥ 5 episodes of monomorphic VT treated with antitachycardia pacing (ATP) regardless of symptoms D: ≥1 appropriate ICD shocks, E: ≥3 monomorphic VT episodes within 24 hours ** VT events must be confirmed by ECG/monitor or ICD download.
Who cannot join
- Unable or unwilling to provide informed consent
- Have received prior radiotherapy to the likely treatment field
- Inotrope-dependent heart failure or an anticipated life-expectancy of < 1 year in the absence of VT
- Presenting arrhythmia: polymorphic VT or ventricular fibrillation (VF)
- Pregnancy
- Active ischemia (acute thrombus diagnosed by coronary angiography, or dynamic ST segment changes demonstrated on ECG) or another reversible cause of VT (e.g. drug-induced arrhythmia), had recent acute coronary syndrome within 30 days thought to be due to acute coronary arterial thrombosis, or have CCS functional class IV angina. Note that biomarker level elevation alone after ventricular arrhythmias does not denote acute coronary syndrome or active ischemia.
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
Nova Scotia Health Authority
Halifax, Nova Scotia, B3H 3A7
Gillian Schraefel, RN, 902 473 7733, Gillian.Schraefel@nshealth.ca
John L Sapp, MD FRCPC
About this study
Official title: Noninvasive Cardiac Radioablation for 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. Current treatment for VT consists of either implantable defibrillators (ICDs), suppressive drug therapy, catheter ablation or a combination of all 3.
Implantable Defibrillators (ICDs) reduce sudden death and can terminate some ventricular tachycardia (VT) without shocks, but they don't prevent VT. The occurrence of ≥1 ICD shock is associated with reductions in mental well-being and physical functioning, and increases in anxiety and sometimes depression. Further, ICD shocks have been consistently associated with adverse outcomes, including heart failure and death. Furthermore, the most important predictor of ICD shocks is a history of prior ICD shocks.
Read more
Therapies to suppress VT include antiarrhythmic drug therapy and catheter ablation, neither however is universally effective. When VT recurs despite antiarrhythmic drug therapy and catheter ablation, novel yet invasive, approaches may be required. Such invasive procedures carry consequent risks of cardiac and extra-cardiac injury.
Stereotactic body radiotherapy (SBRT) is a non-invasive technique that delivers high doses of radiation precisely to specified regions in the body, while minimizing exposure to adjacent tissue. This technique is currently, and commonly used in the treatment of cancer. Conventional application of SBRT has made use of its ability to spare non-target tissue, including for treatment of tumors near the heart. More recently, clinicians have changed the paradigm, by focusing radioablative energy on ventricular scar responsible for ventricular tachycardia. Pre-clinical studies have supported the concept and were followed by first-in-human VT therapeutic experience in 2017. Subsequent studies have had encouraging results for patients who failed or were unable to tolerate conventional treatment.
Read the detailed description
This will be a single centre single arm prospective cohort study. 12 patients with ventricular tachycardia will be recruited from those who have failed or were unable to tolerate conventional therapy. These patients will be recruited from the cardiology clinic where they will already be under the care of a heart rhythm/heart function specialist. Clinical imaging data, medical history and previous ablation data will be collected and use towards planning their treatment with SBRT. Patients will undergo further imaging (unless recently done clinically), including: 4D cardiac CT (cCT), cardiac MRI (cMRI) and a planning CT (pCT). MRIs will only be performed on patients with ICDs for whom it is considered safe to do so. Using the imaging and electroanatomic substrate mapping data collected from a previous ablation attempt, a volumetric modulated arc therapy (VMAT) treatment plan will be established. This treatment plan will be generated in consultation between the cardiac electrophysiologist, radiation oncologist and medical physicist; and will define the target volume (TV) of myocardial tissue to be treated.
Once a TV has been established and verified, patients will be set up on a TrueBeam 1 linear accelerator where the treatment will be administered. The actual time for treatment administration is approximately 30 minutes.
After the procedure, at 6 \& 12 weeks, 7.5 months then every 6 months, 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. Patients will be followed for a minimum of 7.5 months to a maximum of 2 years depending on when they are enrolled.
- Being tested
- Stereotactic Body Radiotherapy (SBRT) ablation of VT
- Medical subject headings
- Tachycardia, Ventricular, Myocardial Infarction
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Stereotactic Body Radiotherapy (SBRT) ablation of VTRadiation
Also called VT Radioablation
Additional imaging for SBRT planning and implementation:
- Planning CT (pCT) - CT simulator that utilizes a respiratory positioning monitoring (RPM) optical tracking system and SBRT immobilization setup to provide necessary data to allow for monitoring of the patient's deep inspiration breath-hold (DIGH) maneuver during treatment delivery.
- SBRT treatment - 30 min procedure on a TrueBeam 1 linear accelerator using SBRT fixation. Patient alignment and DIBH maneuver from the pCT will be replicated using the on-board cone-beam CT (CBCT) guidance and RPM systems.
| Study group | Role | What they receive |
|---|---|---|
| Imaging & SBRT Treatment for Ventricular Tachycardia | Experimental | Not described Receives: Radiation: Stereotactic Body Radiotherapy (SBRT) ablation of VT |
What is being measured
The primary outcome is the main question the study is designed to answer.
Comparative analysis of ventricular arrhythmia events
Number of patients with a reduction in the absolute number of ventricular arrhythmia events following ablation and blanking period, in comparison with those prior to treatment.
Measured: During the first 6 months post blanking period vs. 6 months prior to treatment.
Comparative analysis of targeting methods assessed by volume of sparred healthy tissue
Effectiveness of different myocardial substrate targeting methods on sparing non-target tissue. Delivered treatment approach as compared to a proposed calculated treatment plan using a single phase of the 4DcCT. Measured differences between 2 target-method volumes will equate to the volume of sparred tissue.
Measured: From time of enrollment to 7.5 ,months post treatment.
Secondary outcomes (3)
Number of patients with procedural complications, including: all cause mortality, pericarditis, pneumonitis, heart failure hospitalization and extra-cardiac injury
Composite of; all cause mortality, pericarditis, pneumonitis, heart failure hospitalization and extra-cardiac injury.
Measured: Through study completion,min of 7.5 months to max of 2 years.
Time to Recurrent Arrhythmia Outcomes
Composite of; appropriate ICD shock, VT storm, incessant VT, sustained VT below ICD detection and appropriate antitachycardia pacing.
Measured: Through study completion,min of 7.5 months to max of 2 years
Ventricular arrhythmia Burden
Composite of; number of appropriate shocks, number of inappropriate shocks, number of antitachycardia pacing events.
Measured: During 6 months prior vs. 6 months following treatment.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Nov 2019
- Study start1 Jun 2021
- Primary completion1 Jun 2027 (estimated)
- Study completion1 Sep 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Ventricular TachycardiaStudies of the same condition, open and under way.
- 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
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 12 participants (estimated)
Sponsor and investigators
- Lead sponsor
- John Sapp
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, John Sapp, Nova Scotia Health Authority
- Investigators
- John Sapp, MD FRCPC, Principal investigator, Nova Scotia Health AuthorityJames Clarke, MD FRCPC, Study director, Nova Scotia Health AuthorityJames Robar, Phd FCCPM, Study director, Nova Scotia Health AuthorityJean-Philippe Pignol, MD FRCPC, Study director, Nova Scotia Health Authority
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04162171
- Sponsor's protocol ID
- Sapp007
- Status last verified
- Mar 2026
- First submitted
- 29 Oct 2019
- Last updated
- 18 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 18 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Noninvasive Cardiac Radioablation for Ventricular Tachycardia
- ClinicalTrials.gov ID
- NCT04162171
- Acronym / sponsor ID
- Sapp007
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 12 participants (estimated)
- Lead sponsor
- John SappUniversity, hospital or other
- Study start
- 1 Jun 2021 (actual)
- Primary completion
- 1 Jun 2027 (estimated)
- Study completion
- 1 Sep 2027 (estimated)
- First posted
- 14 Nov 2019 (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.
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. Current treatment for VT consists of either implantable defibrillators (ICDs), suppressive drug therapy, catheter ablation or a combination of all 3.
Implantable Defibrillators (ICDs) reduce sudden death and can terminate some ventricular tachycardia (VT) without shocks, but they don't prevent VT. The occurrence of ≥1 ICD shock is associated with reductions in mental well-being and physical functioning, and increases in anxiety and sometimes depression. Further, ICD shocks have been consistently associated with adverse outcomes, including heart failure and death. Furthermore, the most important predictor of ICD shocks is a history of prior ICD shocks.
Therapies to suppress VT include antiarrhythmic drug therapy and catheter ablation, neither however is universally effective. When VT recurs despite antiarrhythmic drug therapy and catheter ablation, novel yet invasive, approaches may be required. Such invasive procedures carry consequent risks of cardiac and extra-cardiac injury.
Stereotactic body radiotherapy (SBRT) is a non-invasive technique that delivers high doses of radiation precisely to specified regions in the body, while minimizing exposure to adjacent tissue. This technique is currently, and commonly used in the treatment of cancer. Conventional application of SBRT has made use of its ability to spare non-target tissue, including for treatment of tumors near the heart. More recently, clinicians have changed the paradigm, by focusing radioablative energy on ventricular scar responsible for ventricular tachycardia. Pre-clinical studies have supported the concept and were followed by first-in-human VT therapeutic experience in 2017. Subsequent studies have had encouraging results for patients who failed or were unable to tolerate conventional treatment.
Detailed description
This will be a single centre single arm prospective cohort study. 12 patients with ventricular tachycardia will be recruited from those who have failed or were unable to tolerate conventional therapy. These patients will be recruited from the cardiology clinic where they will already be under the care of a heart rhythm/heart function specialist. Clinical imaging data, medical history and previous ablation data will be collected and use towards planning their treatment with SBRT. Patients will undergo further imaging (unless recently done clinically), including: 4D cardiac CT (cCT), cardiac MRI (cMRI) and a planning CT (pCT). MRIs will only be performed on patients with ICDs for whom it is considered safe to do so. Using the imaging and electroanatomic substrate mapping data collected from a previous ablation attempt, a volumetric modulated arc therapy (VMAT) treatment plan will be established. This treatment plan will be generated in consultation between the cardiac electrophysiologist, radiation oncologist and medical physicist; and will define the target volume (TV) of myocardial tissue to be treated.
Once a TV has been established and verified, patients will be set up on a TrueBeam 1 linear accelerator where the treatment will be administered. The actual time for treatment administration is approximately 30 minutes.
After the procedure, at 6 \& 12 weeks, 7.5 months then every 6 months, 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. Patients will be followed for a minimum of 7.5 months to a maximum of 2 years depending on when they are enrolled.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Imaging & SBRT Treatment for Ventricular Tachycardia | Experimental | Radiation: Stereotactic Body Radiotherapy (SBRT) ablation of VT |
Who may qualify
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
Key inclusion criteria (2 listed)
- Structural heart disease: ischemic or non-ischemic cardiomyopathy diagnosed with cardiac imaging demonstrating either segmental myocardial dysfunction, or presence of scar, AND
- One of the following monomorphic VT events despite prior attempted catheter ablation (or contraindication for ablation), AND despite treatment with a class III antiarrhythmic drug (contraindicated, ineffective or not tolerated): A: Documented sustained monomorphic VT terminated by pharmacologic means, DC cardioversion or manual ICD Therapy. B: ≥3 episodes of monomorphic VT treated with antitachycardia pacing (ATP), at least one of which was symptomatic C: ≥ 5 episodes of monomorphic VT treated with antitachycardia pacing (ATP) regardless of symptoms D: ≥1 appropriate ICD shocks, E: ≥3 monomorphic VT episodes within 24 hours ** VT events must be confirmed by ECG/monitor or ICD download.
Key exclusion criteria (6 listed)
- Unable or unwilling to provide informed consent
- Have received prior radiotherapy to the likely treatment field
- Inotrope-dependent heart failure or an anticipated life-expectancy of < 1 year in the absence of VT
- Presenting arrhythmia: polymorphic VT or ventricular fibrillation (VF)
- Pregnancy
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 Body Radiotherapy (SBRT) ablation of VTAlso: VT RadioablationAdditional imaging for SBRT planning and implementation: * Planning CT (pCT) - CT simulator that utilizes a respiratory positioning monitoring (RPM) optical tracking system and SBRT immobilization setup to provide necessary data to allow for monitoring of the patient's deep inspiration breath-hold (DIGH) maneuver during treatment delivery. * SBRT treatment - 30 min procedure on a TrueBeam 1 linear accelerator using SBRT fixation. Patient alignment and DIBH maneuver from the pCT will be replicated using the on-board cone-beam CT (CBCT) guidance and RPM systems. | Radiation | Imaging & SBRT Treatment for Ventricular Tachycardia |
Primary outcome
Comparative analysis of ventricular arrhythmia events
Time frame: During the first 6 months post blanking period vs. 6 months prior to treatment.
Number of patients with a reduction in the absolute number of ventricular arrhythmia events following ablation and blanking period, in comparison with those prior to treatment.
Comparative analysis of targeting methods assessed by volume of sparred healthy tissue
Time frame: From time of enrollment to 7.5 ,months post treatment.
Effectiveness of different myocardial substrate targeting methods on sparing non-target tissue. Delivered treatment approach as compared to a proposed calculated treatment plan using a single phase of the 4DcCT. Measured differences between 2 target-method volumes will equate to the volume of sparred tissue.
3 secondary outcomes
Number of patients with procedural complications, including: all cause mortality, pericarditis, pneumonitis, heart failure hospitalization and extra-cardiac injury
Time frame: Through study completion,min of 7.5 months to max of 2 years.
Time to Recurrent Arrhythmia Outcomes
Time frame: Through study completion,min of 7.5 months to max of 2 years
Ventricular arrhythmia Burden
Time frame: During 6 months prior vs. 6 months following treatment.
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 18 Mar 2026.
- Individual participant dataSharing planned: No
Related trials for Ventricular Tachycardia
Enrolling by invitation
VINTAGE (Ventricular Intramyocardial Navigation for Tachycardia Ablation Guided by Electrograms) Using Commercial Off-The-Shelf (COTS) Catheters
Ventricular Arrhythmia
RecruitingPhase 1
A Study of SGT-501 Gene Therapy in Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT)
Catecholaminergic Polymorphic Ventricular Tachycardia
Recruiting
Safety and Effectiveness of the Sphere-9™ Catheter and Affera™ Ablation System for the Treatment of Ventricular Tachycardia (Sphere VT)
Ventricular Tachycardia
Active, not recruiting
Combined Pulsed Field and Radiofrequency Energy for Ablation of Ventricular Tachycardia
Ventricular Tachycardia (V-Tach)
Recruiting
SPIKE FLOW Endocardial Lead Safety and Performance Study
Acute Myocardial Infarction (AMI), Asystole
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.
John Sapp, MD FRCPC principal investigator
Nova Scotia Health Authority
James Clarke, MD FRCPC study director
Nova Scotia Health Authority
James Robar, Phd FCCPM study director
Nova Scotia Health Authority
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 Body Radiotherapy (SBRT) ablation of VT in people with Ventricular Tachycardia and Myocardial Infarction, run by John Sapp 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 6 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 18 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 Karen Giddens (902 237-5551, karen.giddensl@nshealth.ca), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Comparative analysis of ventricular arrhythmia events (time frame: During the first 6 months post blanking period vs. 6 months prior to treatment.). 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 18 Mar 2026.