Transoesophageal echocardiographic evaluation of pulmonary vein anatomy in patients undergoing ostial radiofrequency catheter ablation for atrial fibrillation: a comparison with magnetic resonance angiography.

Objective: A detailed definition of pulmonary vein (PV) anatomy is of great importance in patients undergoing radiofrequency catheter ablation for atrial fibrillation. In fact, it is known that variations in the number and anatomy of the PV ostia are more frequent than thought. The aim of this study was to assess the usefulness of transoesophageal echocardiography (TOE) in defining the exact PV anatomy by comparing it with magnetic resonance angiography (MRA), which is proven to be very accurate.

Methods: Forty-five consecutive patients (39 male, 6 female, mean age 50 + or - 6 years) affected by drug-refractory atrial fibrillation underwent radiofrequency catheter ablation. They were all studied with MRA and then with TOE in order to exclude intra-atrial thrombi and to assess PV anatomy.

Results: TOE visualised the superior PVs in 100% of cases and the right and left inferior PVs in 98% and 94% of cases, respectively. Only 19 patients (42%) showed typical PV anatomy, with two left and two right distinct PV ostia. In 14 patients (31%), one or two intermediate right PVs and in 12 patients (27%) a common left trunk were detected. The concordance with MRA was high (95%).

Conclusions: TOE is accurate in assessing PV anatomy and in showing anatomic variations in the PV ostia compared with MRA. Anomalous pulmonary venous drainage is more frequent than expected. TOE can provide functional Doppler information, thus being particularly useful in the follow-up after radiofrequency catheter ablation.