Electroanatomic Mapping CT/MR Fusion Models for Stereotactic Radiotherapy Targeting in Ventricular Tachycardia Treatment

Recurrent ventricular tachycardias impair patients’ quality of life significantly. This is caused by two factors – painful defibrillator discharges and the fear of them recurring. Currently available pharmacological and instrumental procedures are effective in 50% of patients on average. The so-called „bailout procedures“ are used in nonresponders, although the data supporting these are scarce. Stereotactic radiotherapy is one of them, being an innovative way of applying radiation beams not to tumour tissue, but to scar tissue in the heart muscle, which is often a cause of the recurrent ventricular tachycardia. Precisely targeted radiation application is of paramount importance for both efficiency and safety of this currently evolving technology. The main limit of the procedure is the accuracy of information transmitted from the electroanatomic mapping to the planning software of the irradiation device. To our knowledge, no method to convert substrate information into planning CT images has been developed so far.