Accuracy of epicardial electroanatomic mapping and ablation of sustained ventricular tachycardia merged with heart CT scan in chronic Chagasic cardiomyopathy.

BACKGROUND: As damage to coronary arteries is a potential complication of epicardial RF catheter ablation (EPRFCA), the procedure must be associated with coronary angiography. Chronic Chagasic cardiomiopathy (CCC) is a disease where epicardial VT are common. Eletroanatomic mapping merged with computed totmography (CT) scan data is a useful tool for mapping the endocardium, and its accuracy in guiding ablation on the epicardium was not adequately evaluated so far.

OBJECTIVE: Compare electronatomic map merged with Heart CT to fluoroscopy for epicardial ablation of CCC. Describe the distribution of the scars on CCC.

METHODS AND RESULTS: We performed epicardial and endocardial mapping and ablation using CARTO XP V8 on eight patients and merged the map with coronary arteries CT scan using at least three landmarks. To compare the 3D image obtained with CARTO MERGE and the 2D fluoroscopic image obtained during the ablation procedure, we used computer graphic software (Inkscape™) in order to prove that the images were equivalent and to compare the distance between the catheter tip on fluoroscopy to catheter tip on 3D EA map. EPRFCA was successfully performed in all patients and they did not present recurrence for at least 3-month follow-up. The mean difference between the tip of the catheter on fluoroscopy and on the 3D model was 6.03 ± 2.09 mm. Scars were present in the epicardium and endocardium and most of patients presented with posterior wall scars and RV scar.

CONCLUSION: The combination of electroanatomic map and CT coronary artery scan data is feasible and can be an important tool for EPRFCA in patients with CCC and VT.