Catheter Ablation of Hemodynamically Unstable Ventricular Tachycardia in a Patient with Dextro - Transposition of the Great Arteries and Mustard's Repair.

INTRODUCTION: A patient with D-TGA and surgical repair (Mustard's procedure) presented with appropriate ICD shocks due to monomorphic ventricular tachycardia, refractory to antiarrhythmic medications. METHODS AND RESULTS: The patient underwent an electrophysiological study and catheter ablation for the VT. Substrate and pace mapping techniques, with the help of an electroanatomical mapping system, was used to localize and ablate the tachycardia successfully. CONCLUSIONS: In patients with D-TGA and Mustard's repair, scar tissue resulting from VSD repair can act as a substrate for recurrent VT. Catheter ablation of VT is useful in management of VT that occurs despite antiarrhythmic therapy and/or when it is unstable.