Comparison of transthoracic echocardiography with computed tomography in evaluation of pulmonary veins

Transesophageal echocardiography may be used to assess pulmonary veins for atrial fibrillation ablation. No study focused on the role of transthoracic echocardiography (TTE) in evaluating the diameter and anatomy of pulmonary veins.

Among 142 atrial fibrillation patients (57.7% men; mean age, 60.5) hospitalised for catheter ablation, we assessed pulmonary veins and compared the measurements by TTE with cardiac computed tomography (CT) before ablation. Among 17 patients who had follow-up examinations, the second measurements were also studied.

TTE identified and determined the diameters of 140 (98.6%) right and 140 (98.6%) left superior PVs, and 136 (95.7%) right and 135 (95.1%) left inferior PVs. A separate middle PV ostia was identified in 14 out of the 22 patients (63.6%) for the right side and in 2 out of 4 (50.0%) for the left side. The PV diameters before ablation assessed by CT vs. TTE were 17.96 vs. 18.07 mm for right superior, 15.92 vs. 15.51 mm for right inferior, 18.54 vs. 18.42 mm for left superior, and 15.56 vs. 15.45 mm for left inferior vein. The paired differences between the assessments of CT and TTE were not significant (P ≥ 0.31) except for the right inferior vein with a CT-minus-TTE difference of 0.41 mm (P = 0.018). The follow-up PV diameters by both CT (P ≥ 0.069) and TTE (P ≥ 0.093) were not different from baseline measurements in the 17 patients who had follow-up measurements.

With a better understanding of PV anatomy in TTE imaging, assessing PV diameters by non-invasive TTE is feasible. However, the clear identification of anatomic variation might still be challenging.