Limitation
This is a single-center study of a small number of patients. Although ECG and Holter monitoring was regularly performed during the 1-year follow-up, AF recurrence may be underestimated. The ICE catheter was placed in the LA to obtain a clear image of the area surrounding the PV. Nevertheless, this may still cause angulation errors in the direction of the ultrasound beam perpendicular to the LA/PV surface and distort the measurement.