Catheter Ablation -> Ventricular Arrhythmias -> Ablation Techniques D-PO01 - Featured Poster Session (ID 11) Poster

D-PO01-141 - Cardiac Imaging Identifies Features Associated With Reduced Survival After Noninvasive Cardiac Radioablation (ID 936)


Background: Noninvasive cardiac radioablation has been used for treatment of refractory VT. Cardiac imaging was used to guide treatment. We hypothesized that survival is associated with cardiac imaging features.
Objective: To identify patients at higher risk for death after radioablation using pre-procedural cardiac imaging.
Methods: Patients (n=19) received a single 25 Gray fraction to a discrete ventricular target as part of the ENCORE-VT prospective trial. VT was suppressed in 18/19 (95%) of patients. Echocardiograms and cardiac MRI were evaluated in a blinded fashion. MRIs underwent automatic contouring and myocardial strain analysis (Medis). Patients were grouped into survivors (n=8, median survival 27.7 months) and those who received cardiac transplant or died (n=11, median survival 11.2 months). Unpaired t-tests were used to compare baseline cardiac imaging features between groups.
Results: Using echo (n=19), the non-survivor group had higher LV end diastolic volume (mean 268 vs. 180 mL, p<0.005) and LV end systolic volume (mean 200 vs. 125, p<0.005). No difference was observed for LV ejection fraction (LVEF mean 28% vs. 29%) or wall segment scores. Using cardiac MRI (n=9), the non-survivor group had lower LVEF (mean 13% vs. 25%, p=0.04), stroke volume (mean 34 vs. 61 mL, p=0.007), global circumferential strain (-5.0 vs. -10.9, p=0.04) and more myocardial scar (mean 42% vs. 27%, p=0.047).
Conclusion: Survival after cardiac radioablation was associated with features of severely advanced cardiomyopathy. These results may be helpful to identify patients for future clinical trials.