Evaluation of 3D guided electroanatomic mapping for ablation of atrial fibrillation in reference to CT-Scan image integration.

<bold>Background: </bold>Anatomical guided atrial fibrillation (AF) catheter ablation relies on the assumption that the left atrium reconstruction anatomy (LARA) using a 3D mapping system precisely matches the patient's CT scan anatomy (real anatomy). This study investigates whether this postulation is accurate using CT scan image integration.<bold>Patients and Methods: </bold>Thirty consecutive patients (23 men, mean age = 51.9 +/- 9.9 years) with symptomatic drug-refractory paroxysmal (n = 21) or persistent (n = 9) AF underwent a circumferential, 2 x 2, pulmonary vein (PV) radiofrequency (RF) ablation using the CARTOMERGE system. Left atrium (LA) anatomy was first reconstructed and RF design lines drawn on this LARA. After a CT-scan image of the LA was integrated into the 3D system, RF lesions were deployed 10 +/- 5 mm outside the PV ostia (PVO) onto the CT-scan LA surface. The match between the actual RF lines and the RF design lines was analyzed off-line after catheter withdrawal.<bold>Results: </bold>Circumferential RF design lines were divided into four segments encircling both the right and left PVs. Design segments matched the actual RF segments in a proportion varying from 23% up to 83%. A mean of 2.8 +/- 1.6 segments per patient were inaccurately designed that extended a mean of 3.8 +/- 2.3mm inside the adjacent PV or 6.7 +/- 1.8mm inside the left atrial appendage (LAA). Seven patients (23%) had four or more segments incorrectly designed.<bold>Conclusions: </bold>Our study reveals the inaccuracy of 3D anatomic guided RF ablation with respect to the LA anatomical structures that could be possibly improved when combined with CT-scan image integration. [ABSTRACT FROM AUTHOR]