Stereotactic arrhythmia radioablation with inHEART-guided targeting achieved >75% ventricular tachycardia reduction in 78% of patients at 12 months.
Observational (n=18)
No
Does stereotactic arrhythmia radioablation with inHEART-guided targeting reduce VT burden and ICD shocks in patients with refractory ventricular tachycardia?
Integrating the inHEART multimodality platform for stereotactic arrhythmia radioablation is feasible and safe, leading to significant reductions in VT burden and ICD shocks in patients with refractory VT.
PURPOSE To present the clinical workflow developed for stereotactic arrhythmia radioablation (STAR), with a particular focus on the inHEART multimodality platform used for cardiac imaging integration and 3D substrate segmentation. We also report the clinical outcomes and dosimetric results of the initial 18 patients treated. METHODS AND MATERIALS All patients underwent contrast-enhanced cardiac computed tomography (CT), including late enhancement imaging and optional cardiac magnetic resonance imaging (MRI). Imaging data were processed using the inHeart multimodality platform for specific imaging in cardiology (MUSIC), which enabled automatic 3D segmentation of cardiac anatomy, identification of the scar substrate, and integration of electrophysiological data to define the clinical target volume (CTV). The stereotactic body radiation therapy (SBRT) inHEART module exported target structures in digital imaging and communications in medicine-radiotherapy (DICOM-RT) format to the Eclipse treatment planning system. 4D-CT simulation scans were acquired to account for cardiorespiratory motion, and an internal target volume/planning target volume (ITV/PTV) was derived accordingly on expiratory phases. Treatment was delivered with volumetric modulated arc therapy (VMAT) in a single fraction of 25 Gy to the PTV using a TrueBeamTM STx linac. Clinical effectiveness was assessed through ventricular tachycardia (VT) burden and implantable cardioverter-defibrillators (ICD) shock reduction. RESULTS Median CTV, ITV, and PTV volume were 14.50 cc (range, 4.32-32.6), 22.13 cc (range, 5.15-49.15), and 58.42 cc (range, 20.87-109.76), respectively. Excellent dose coverage was achieved, median PTV D99% was 25.25 Gy (range, 21.94-27.51), with a mean Paddick conformity index of 0.89 ± 0.08. All organs at risk (OARs) met the dose constraints. At 12 months, 78% of patients showed > 75% VT reduction, and 94% of surviving patients experiencing a limited number of shocks (<2). CONCLUSIONS Integrating the inHEART SBRT module within a standardized multimodal imaging workflow enables accurate STAR planning and delivery. This approach proved feasible, robust, and safe for managing refractory VT.
BRUN et al. (Sun,) conducted a observational in Refractory ventricular tachycardia (n=18). Stereotactic arrhythmia radioablation (STAR) with inHEART-guided targeting was evaluated on > 75% ventricular tachycardia reduction. Stereotactic arrhythmia radioablation with inHEART-guided targeting achieved >75% ventricular tachycardia reduction in 78% of patients at 12 months.