Successful radiofrequency ablation in patients with previous atrial fibrillation results in a significant decrease in left atrial size

Background - The objective of the present study was to evaluate the relation between freedom from atrial fibrillation ( AF) and left atrial ( LA) size in patients who underwent circumferential pulmonary vein (PV) isolation and LA ablation. Methods and Results - One hundred five consecutive patients with symptomatic and drug-refractory paroxysmal or persistent AF were included in the present study. The mean age was 52 +/- 9.5 years ( range, 27 to 75 years); 74 patients ( 70%) were male. Paroxysmal AF was present in 52 ( 49.5%) and persistent AF in 53 (50.5%) patients. Mean AF duration was 6.0 +/- 5.1 years in the paroxysmal AF group and 7.6 +/- 6.0 years in the persistent AF group. A 3D electroanatomic map of the LA including the PV ostia was constructed with a nonfluoroscopic navigation system (Carto, Biosense Webster). Left- and right-sided PVs were encircled by continuous radiofrequency ablation lines. We performed 128 ablation procedures in 105 patients, ie, 23 redo procedures. The mean long-term follow-up duration was 14.6 +/- 4.9 months ( range, 6 to 24 months). Sinus rhythm was present in 45 patients ( 86.5%) in the paroxysmal AF group and in 41 patients ( 77.3%) in the persistent AF group at the latest follow-up. Six months after ablation, LA dimension in the persistent AF subjects who remained in sinus rhythm decreased from 44.0 +/- 5.8 to 40 +/- 4.5 mm ( range, 31 to 51 mm). In contrast, in patients with recurrences of AF, LA dimension increased from 45 +/- 6.5 to 49 +/- 5.4 mm ( range, 32 to 59 mm). In the successfully treated paroxysmal AF group, LA dimension decreased from 40.5 +/- 4.4 to 37.5 +/- 3.5 mm ( P < 0.01). Conclusions - In radiofrequency ablation of AF using an electroanatomic approach, there is a statistically significant relationship between medium-term procedural success and LA size: persistent sinus rhythm is associated with reduced and recurrent AF with increased LA dimensions.