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

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.

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.

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.

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.