Stereotactic body radiotherapy for ventricular tachycardia (cardiac radiosurgery) : First-in-patient treatment in Germany.

PURPOSE: Single-session cardiac stereotactic body radiotherapy, called cardiac radiosurgery (CRS) or radioablation (RA), may offer a potential treatment option for patients with refractory ventricular tachycardia (VT) and electrical storm who are otherwise ineligible for catheter ablation. However, there is only limited clinical experience. We now present the first-in-patient treatment using (CRS/RA) for VT in Germany. METHODS: A 78-year-old male patient with dilated cardiomyopathy and significantly reduced ejection fraction (15%) presented with monomorphic VT refractory to poly-anti-arrhythmic medication and causing multiple implantable cardioverter-defibrillator (ICD) interventions over the course of several weeks, necessitating prolonged treatment on an intensive care unit. Ultra-high-resolution electroanatomical voltage mapping (EVM) revealed a re-entry circuit in the cardiac septum inaccessible for catheter ablation. Based on the EVM, CRS/RA with a single session dose of 25 Gy (83% isodose) was delivered to the VT substrate (8.1 cc) using a c-arm-based high-precision linear accelerator on November 30, 2018. RESULTS: CRS/RA was performed without incident and dysfunction of the ICD was not observed. Following the procedure, a significant reduction in monomorphic VT from 5.0 to 1.6 episodes per week and of ICD shock interventions by 81.2% was observed. Besides periprocedural nausea with a single episode of vomiting, no treatment-associated side effects were noted. Unfortunately, the patient died 57 days after CRS/RA due to sepsis-associated cardiac circulatory failure after Clostridium difficile-associated colitis developed during rehabilitation. Histopathologic examination of the heart as part of a clinical autopsy revealed diffuse fibrosis on most sections of the heart without apparent differences between the target area and the posterior cardiac wall serving as a control. CONCLUSION: CRS/RA appears to be a possible treatment option for otherwise untreatable patients suffering from refractory VT and electrical storm. A relevant reduction in VT incidence and ICD interventions was observed, although long-term outcome and consequences of CRS/RA remain unclear. Clinical trials are strongly warranted and have been initiated.

Deceleration capacity: A novel predictor for total mortality in patients with non-ischemic dilated cardiomyopathy.

OBJECTIVES: We hypothesized that deceleration capacity (DC), a novel marker of cardiac autonomic modulation, is an independent predictor for mortality in patients with non-ischemic dilated cardiomyopathy (NICM). BACKGROUND: NICM is associated with a high risk for sudden cardiac death (SCD). However there are no clinically established parameters available for risk stratification beyond LVEF. DC has been previously shown to be a strong independent predictor for total mortality in patients after myocardial infarction. METHODS: Holter-ECG recordings of 201 patients NICM (83.1% male, mean age: 61.4years, mean LVEF: 33.3%) were analyzed by the method of phase-rectified-signal-averaging (PRSA) to obtain DC. RESULTS: During a minimum follow-up of 40month 59 patients died. Kaplan Meyer Analysis showed a significantly higher mortality in patients with a DC below 4.5ms (log rank p=0.012) irrespective to the presence of atrial fibrillation. CONCLUSIONS: Impaired DC is a powerful independent predictor for mortality in patients with NICM.