Role of transoesophageal echocardiography in evaluating the effect of catheter ablation of atrial fibrillation on anatomy and function of the pulmonary veins

Abstract

Radiofrequency ablation (ABL) of pulmonary veins (PVs) is an effective treatment of atrial fibrillation (AF). The aim of this study was to evaluate the possible morphological and functional consequences of this procedure on PV during a 12-month follow-up. Ninety-six patients underwent transoesophageal echocardiography (TEE) before ABL, and 48 h, 3, and 12 months later. The peak velocity, mean velocity, mean/peak flow velocity, and diameter of each vein were measured at every follow-up examination. All patients also underwent multidimensional computer tomography (MCT) 3 months after ABL. At the first control, a 5% reduction in PV diameters and an increase in the peak velocity, mean velocity, and mean/peak velocity (34.3, 42.2, and 6.9, respectively: P < 0.000) of their Doppler flow were observed. Later follow-up examinations revealed no further significant increase in PV narrowing or flow velocities. MCT showed PV stenoses (>50%) in four PVs, while TEE showed a >100% increase over basal values in flow velocities and a plateau configuration of the pulsed-wave Doppler spectrum. ABL of AF reduces the diameter and increases the flow velocities of PV. However, critical stenosis is rare and can be diagnosed by TEE through a marked change in the velocities and in the configuration of the Doppler flow.