Usefulness of magnetic resonance in the analysis of the anatomy of the pulmonary veins in patients with atrial fibrillation waiting for radiofrequency ablation

Nowadays, pulmonary veins (PV) ablation in patients with symptomatic drugs refractory atrial fibrillation (AF) has become the treatment of choice. Objective: To determine the usefulness of Magnetic Resonance (MR) of left atrial and pulmonary veins as reference anatomic parameter for navigation systems in patients who are going to be submitted to AF radiofrequency ablation. Material and Methods: This is a retrospective case control study, which included 91 consecutive patients with AF diagnosis waiting for ablation between July 2014 and December 2017. The studied population was a mean 58.2 years old (range: 21-82 years old), and 72.5% were men. MR and the EnSite navigation system imaging were compared. Patients with the presence of left atrial/appendage clot were excluded. Results: Our studied population presented more frequently an anatomic pattern of four PV. Supernumerary PV was the anatomic variant found in the majority of cases, with all patients showing a right intermediate vein. The common branch/ostium was the less usual variant, and it was left sided in all cases. The MR pulmonary veins anatomic analysis showed a substantial concordance with the EnSite navigation system, making the radiofrequency ablation planning easier. Conclusions: MR is an efficient, safe and simple tool which is highly precise in the evaluation of the anatomy of the left atrium and the PVs, so that its integration to navigation systems should be disseminated. (authors)