Background: Stereotactic body radiation therapy (SBRT) has emerged as a safe and effective strategy for performing scar homogenization in patients with ventricular tachycardia (VT) refractory to anti-arrhythmic therapy and catheter ablation. Outcomes of SBRT in patients with left ventricular assist devices (LVADs) are unknown.
Objective: We describe a case of SBRT in a 58-year-old male with non-ischemic cardiomyopathy (EF 25%), ICD and LVAD (Heart Mate 3) who presented with VT storm and recurrent ICD shocks refractory to anti-arrhythmic medications and three prior catheter-based VT ablations (including epicardial approach).
Results: Electrophysiology study induced multiple VTs with exit sites localized to a large area of scar in the LV basal anterior wall (Figure 1, left) that persisted despite extension endocardial and needle-based catheter ablation. The decision was made to proceed with SBRT. The patient underwent CT simulation to demarcate the basal scar region and ensure appropriate separation from the infero-posterior LVAD insertion site (Figure 2, right). SBRT was then performed with a dose of 2,500 centigray in one fraction using a 6-megavolt flattening filter-free photon beam. Adjacent normal structures were shielded with a multi-leaf collimator. The patient tolerated radiation treatment without complications and remained free of VT up to discharge a week later.
Conclusion: SBRT for VT can be safely performed in patients with LVAD if the region of treated scar is remote from the LVAD insertion site. Further studies are needed to determine minimum safe distance between scar and LVAD insertion site, and the impact of SBRT on long-term LVAD function.