Abstract 2873: Left Atrial Size and Mechanical Function after Radiofrequency Catheter Ablation for Paroxymal Atrial Fibrillation
Background: Segmental pulmonary vein isolation (SPVI) and circumferential pulmonary vein ablation (CPVA) both may eliminate paroxysmal artial fibrillation (PAF). The aim of the study is to evaluate the impact of the two different strategies on the left atrum (LA) size and function in patients with PAF.
Methods and Results: Of 66 consecutive patients with symptomatic PAF, 30 patients underwent SPVI and 36 underwent CPVA. Transthorax echocardiography was performed at baseline and at 1-day, 1-month, 3-month intervals after ablation. LA dimension, LA area, late diastolic peak velocity of mitral valve inflow (A) and peak atrail systolic mitral annulus velocity (A’) were recorded. After a mean follow-up of 315±153 days, 21 patients (70%) after SPVI and 28 patients (76%) after CPVA were free of atrial tachyarrhythmia (p=0.650). As compared with the baseline, LA area decreased at 1-month after ablation in SPVI group and at 3-month in CPVA group. LA dimension decreased also in SPVI group, but not in CPVA group. A velocity and A’velocity declined remarkably 1 day after CPVA, and restored 3 months later. The former went back to the lever of baseline, and the latter exceeded it apparently. In SPVI group, A velocity increased at 1-month, and the increase maintained in 3-month. A’ velocity increased at 3-month after ablation. No reduction of A velocity or A’ velocity was found after SPVI.
Conclusions: This study demonstrates a decrease in LA area and an improvement in LA systolic function 3 months after ablation for PAF. The LA damage by CPVA is more than that by SPVI, which is characterized by the reduction of LA function 1 day after procedure and the delayed improvement of LA size and functional parameters.