Comparing cardiac radioablation and repeat catheter ablation for high-risk ventricular tachycardia

Cardiac RADIoablation Versus Repeat Catheter Ablation: a Pivotal Randomized Clinical Trial Evaluating Safety and Efficacy for Patients With High-risk Refractory Ventricular Tachycardia

This study is testing whether a new treatment called cardiac radioablation is better than repeat catheter ablation for people with high-risk ventricular tachycardia who have had their heart rhythm problems come back.

Quick facts

• Phase: NA
• Study type: Interventional
• Enrollment: 380 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Varian, a Siemens Healthineers Company (industry)
• Drugs / interventions: radiation
• Locations: 11 sites (Los Angeles, California and 10 other locations)
• Trial ID: NCT05765175 on ClinicalTrials.gov

What this trial studies

RADIATE-VT is a pivotal, multicenter, randomized trial that evaluates the safety and efficacy of cardiac radioablation (CRA) using the Varian CRA System compared to repeat catheter ablation (CA) in patients with high-risk refractory ventricular tachycardia (VT). The study focuses on individuals who have experienced VT recurrence after previous catheter ablation and are candidates for additional procedures. Participants will be monitored for outcomes related to VT management and overall cardiac health.

Who should consider this trial

Good fit: Ideal candidates include patients with high-risk refractory VT who have previously undergone catheter ablation and have experienced VT recurrence.

Not a fit: Patients who do not have recurrent ventricular tachycardia or those who are not candidates for repeat catheter ablation may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide a new treatment option that may improve outcomes for patients with refractory ventricular tachycardia.

How similar studies have performed: Other studies have explored catheter ablation techniques, but the specific approach of cardiac radioablation in this context is relatively novel.

Eligibility criteria

Inclusion Criteria:

1. High-risk refractory VT, defined as:

   1. Ischemic and/or nonischemic cardiomyopathy, and
   2. Recurrent sustained monomorphic VT, defined as at least one of the following below, documented by ICD interrogation or ECG in the prior 6 months, and having occurred after the last VT ablation:

      A: ≥3 episodes of monomorphic VT treated with anti-tachycardia pacing (ATP) at least one of which is symptomatic

      B: ≥1 appropriate ICD shock

      C: ≥3 episodes of sustained monomorphic VT within 24 hours treated with ICD shock or ATP

      D: sustained monomorphic VT below detection rate of ICD documented by ECG, and
   3. Left ventricular ejection fraction (LVEF) ≤49% and
   4. Previously underwent at least one standard of care CA for VT.
2. Presence of a clinical indication for a repeat CA procedure for scar-mediated VT in the judgement of the treating investigator.
3. Has failed amiodarone therapy or is intolerant to amiodarone:

   * Failed amiodarone therapy is defined as: appropriate ICD therapy or sustained monomorphic VT having occurred while the patient was taking amiodarone (minimum cumulative dose of 10 g).
   * Intolerant to amiodarone is defined as: previously tried or taken amiodarone but stopped due to medication related side effects or toxicities.
4. Deemed to be medically and technically a candidate for further CA by the electrophysiologist investigator.
5. Presence of an ICD.
6. At least 18 years of age (or meets local age of majority).
7. Ability to understand and willingness to sign an IRB approved written informed consent document.

Exclusion Criteria:

1. Contraindication to a CA procedure for VT (e.g., presence of mobile LV thrombus, active systemic infection, active ischemic or other reversible causes of VT).
2. Patients with expected, right ventricular scar only.
3. Any prior radiation to the thorax region of the body.
4. Known medical conditions associated with higher risk of radiotherapy complications in the judgement of the radiation oncologist (i.e., active connective tissue disorders, interstitial lung disease, etc.) that would preclude safe delivery of CRA.
5. Current use of inotropes.
6. Presence of a left-ventricular assist device (LVAD).
7. Scheduled for LVAD or heart transplant procedures.
8. Presence of a systemic illness likely to limit survival to \< 1 year.
9. VT ablation procedure performed within the prior 2 weeks.
10. Polymorphic VT or ventricular fibrillation (VF) as the primary clinical heart rhythm, as indicated by 12-lead ECG and/or ICD interrogation.
11. \>3 distinct clinical monomorphic VT morphologies on ICD interrogation since the prior CA, or \>5 induced monomorphic VT morphologies during NIPS testing.
12. Incessant VT that is hemodynamically unstable.
13. Bundle branch reentry (BBR) VT.
14. Pregnant and/or breastfeeding. (Patient denial is sufficient for enrollment).
15. Patients of childbearing potential who:

    * are not on a medically effective means of birth control at the time of screening or do not start a medically effective means of birth control prior to randomization; or
    * do not agree to continue medically effective means of birth control until they have completed their assigned therapy; or
    * do not agree to be on a medically effective means of birth control if they are treated with CRA after their index CA procedure.
16. Patients enrolled in another clinical study the investigator believes to be in conflict with this clinical investigation.
17. Patients enrolled or planned to be enrolled in another cardiac radioablation clinical study or registry.
18. Patients with any other medical condition or laboratory value that would, at the discretion of the investigator, preclude the patient from participation in this clinical investigation.

Where this trial is running

Los Angeles, California and 10 other locations

• Cedars-Sinai Medical Center — Los Angeles, California, United States (RECRUITING)
• Hartford Hospital — Hartford, Connecticut, United States (RECRUITING)
• Brigham & Women's Hospital — Boston, Massachusetts, United States (RECRUITING)
• Mayo Clinic — Rochester, Minnesota, United States (RECRUITING)
• University of Missouri — Columbia, Missouri, United States (RECRUITING)
• Washington University — St Louis, Missouri, United States (RECRUITING)
• The Ohio State University — Columbus, Ohio, United States (RECRUITING)
• University of Pennsylvania — Philadelphia, Pennsylvania, United States (RECRUITING)
• University of Pittsburgh Medical Center — Pittsburgh, Pennsylvania, United States (RECRUITING)
• Medical University of South Carolina — Charleston, South Carolina, United States (RECRUITING)
• Vanderbilt University Medical Center — Nashville, Tennessee, United States (RECRUITING)

Study contacts

• Study coordinator: Claire McCann, PhD

Conditions: Tachycardia, Ventricular, Cardiac radioablation, Ventricular tachycardia, Catheter ablation, Refractory ventricular tachycardia, High risk, SBRT