Safety and Efficacy of Stereotactic Cardiac Radio-Ablation for Ventricular Tachycardia in Patients at High Risk of Mortality

BACKGROUND: Patients who have recurrent ventricular tachycardia (VT) despite receiving antiarrhythmic drugs (AADs), implantable cardioverter defibrillator placement, and catheter ablation (CA) are at significant risk of morbidity and mortality. METHODS: We offered completely noninvasive cardiac radio-ablation (CRA) on a "compassionate use" basis for patients who were unable or unwilling to undergo CA for recurrent VT despite their having received treatment with AADs and placement of an implantable cardioverter defibrillator. All patients who were referred to the CRA program were entered into a prospective registry and followed indefinitely thereafter. RESULTS: A total of 20 patients were referred for CRA, and 10 elected to undergo the treatment as outpatients. Ten patients declined CRA therapy, owing to fear of complications and/or logistic concerns relating to attending multiple hospital visits; they received escalated drug therapy. All patients who were referred to and were agreeable to CRA received CRA. No patients were excluded or were denied CRA by clinicians for any reason, and all patients were followed clinically. The VT burden decreased significantly, by > 90% (both anti-tachycardia pacing and shocks), and 1 patient died of a cardiovascular cause at 1 year following a single CRA treatment of 25 Gy. One patient experienced steroid-responsive pneumonitis as an adverse event post-CRA (common terminology criteria for adverse events [CTCAE] grade 2). For the 10 patients who declined CRA, no appreciable reduction in VT occurred, despite their receipt of increasing dosages of AADs, and 5 patients died of cardiovascular causes within 1 year. CONCLUSIONS: Noninvasive stereotactic CRA is well tolerated with good short-term efficacy for recurrent VT on a "compassionate use" basis. Prospective randomized controlled trials to determine the relative efficacy of CA vs CRA for VT are urgently required.