Stereotactic radioablation for the treatment of ventricular tachycardia: preliminary data and insights from the STRA-MI-VT phase Ib/II study

Abstract

Purpose We present the preliminary results of the STRA-MI-VT Study (NCT04066517), a spontaneous, phase Ib/II study, designed to prospectively test the safety and efficacy of stereotactic body radiotherapy (SBRT) in patientswith advanced cardiac disease and intractable ventricular tachycardia (VT). Methods Cardiac computed tomography (CT) integrated by electroanatomical mapping was used for substrate identification and merged with dedicated CT scans for treatment plan preparation. A single 25-Gy radioablation dose was delivered by a LINAC-based volumetric modulated arc therapy technique in a non-invasive matter. The primary safety endpoint was treatment-related adverse effects during acute and long-term follow-up (FU), obtained by regular in-hospital controls and implantable cardioverter defibrillator (ICD) remote monitoring. The primary efficacy endpoint was the reduction at 3 and 6 months of VT episodes and ICD shocks. Results Seven out of eight patients (men; age, 70 ± 7 years; ejection fraction, 27 ± 11%; 3 ischemic, 4 non-ischemic cardiomyopathies) underwent SBRT. At a median 8-month FU, no treatment-related serious adverse event occurred. Three patients died from non-SBRT-related causes. Four patients completed the 6-month FU: the number of VT decreased from 29 ± 33 to 11 ± 9 (p = .05) and 2 ± 2 (p = .08), at 3 and 6 months, respectively; shocks decreased from 11 to 0 and 2, respectively. At 6 months, all patients. showed a significant reduction of VT episodes and no electrical storm recurrence, with the complete regression of iterative VTs in 2/2 patients. Conclusion The STRA-MI-VT Study suggests that SBRT can be considered an alternative option for the treatment of VT in patients with structural heart disease and highlights the need for further clinical investigation addressing safety and efficacy.

Case Report: Repeated Stereotactic Radiotherapy of Recurrent Ventricular Tachycardia: Reasons, Feasibility, and Safety

“…The experience with SBRT is gradually growing and several other case reports and prospective clinical studies documented a significant decrease in VT occurrences ( 9 – 19 ). However, even this strategy can fail for various reasons.…”

Feasibility of an Automatic Ultrasonographic Image Acquisition System Associated With an Artificial Intelligence Algorithm for Real-Time Monitoring of Cardiac Motion During Cardiac Radio-Ablation

“…Some considerations can be made about the representativeness of the enrolled population compared to the population potentially eligible for radio-ablation treatment. The average age of the patients enrolled, as well as the percentage of females and the spectrum of underlying cardiac disorders, are globally in line with that of the types of patients who could benefit from STAR ( 6 , 11 , 18 ). All body sizes were coved, as well as all ranges of left ventricle ejection fraction, including patients with a markedly depressed left ventricle systolic function, that are at present the main candidates for STAR ( 6 ).…”

“…All body sizes were coved, as well as all ranges of left ventricle ejection fraction, including patients with a markedly depressed left ventricle systolic function, that are at present the main candidates for STAR ( 6 ). Previous clinical studies on STAR did not systematically report on cardiac rhythm stability during treatment, however it appears plausible, even considering the percentage of patients with dual-chamber ICD and CRT ( 18 ), that the population included in our study, even in this respect, was representative of the cohort of patients eligible for STAR.…”

Stereotactic Radiotherapy: An Alternative Option for Refractory Ventricular Tachycardia to Drug and Ablation Therapy

“…Carbucicchio et al [ 44 ] presented the preliminary results of their spontaneous, prospective, single-arm, phase Ib/II single-center STRA-MI-VT Study. The study investigated the safety and efficacy of SBRT in eight patients with intractable VT. Of the seven patients who underwent SBRT (mean age, 70 ± 7 years; ejection fraction, 27 ± 11%), three had ischemic and four had non-ischemic cardiomyopathy.…”