Abstract
Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory atrial fibrillation (AF). However, it is still challenging because of the high degree of variability of the pulmonary vein (PV) anatomy. Three-dimensional transesophageal echocardiography (TEE) is a promising new technique for cardiac imaging. Therefore, we have evaluated the usefulness of 3-D TEE for analysing the left atrial anatomy prior to an ablation procedure in comparison to magnetic resonance imaging (MRI).
Methods
In 120 patients, 3-D TEE and cardiac MRI were performed immediately prior to an ablation procedure (paroxysmal AF: 50 patients, persistent AF: 70 patients). The image quality provided by 3-D TEE and by cardiac MRI was compared in all patients. Two different ablation strategies were used. In patients with paroxysmal AF, the cryoablation technique was used. In the other patients, a circumferential pulmonary vein ablation was performed using a three-dimensional mapping system.
Results
A 3-D TEE and a cardiac MRI could be performed successfully in all patients prior to the ablation procedure. Several variations of the PV anatomy could be visualized precisely by 3-D TEE and cardiac MRI (e.g. accessory PVs, common PV ostia, varying diameter of the left atrial appendage and its distance to the left superior PV). The image quality was good in the majority of patients even if AF with rapid ventricular response was present during the examination. The image quality provided by 3-D TEE was acceptable in 116/120 patients (96.7 %). The TEE findings correlated well with the PV angiographies performed using cardiac MRI. There was a good correlation with regard to the diameter of the PV ostia assessed by these two imaging techniques. All ablation procedures could be performed successfully (mean number of completely isolated PVs: 3.9 (cryo group), 4.0 (radiofrequency catheter ablation group)). At 42-month follow-up, 70.0 % of all patients were free from an arrhythmia recurrence (cryo group: 76.0 %, Carto group: 65.7 %). There were no major complications.
Conclusions
AF ablation procedures can be performed safely and effectively based on prior 3-D TEE imaging. The image quality was acceptable in the vast majority of patients.
Catheter Ablation of Atrial Fibrillation: Three-dimensional Transesophageal Echocardiography Provides an Excellent Overview over the Pulmonary Vein Anatomy Facilitating Radiofrequency and Cryoablation Procedures
