AIM  To investigate the associated factors of sinus rhythm(SR) maintenance in patients with paroxysmal atrial fibrillation(PAF) after catheter ablation(CA).

  METHODS  Clinical, transthoracic echocardiograpy(TTE) and transesophageal echocardiograpy(TEE) data of 255 PAF patients with successful CA were analyzed for assessment of 1-year maintenace of SR.

  RESULTS  At 1-year followup, 188 of 255(74%) patients continued to have SR. Significant differences were observed between SR maitenance group(n=188) and late recurrence group(n=67) in LVEF(58±4)% vs (57±5)%, P<0.05, left atrial appendage emptying velocity(LAA-EV)(56±11) cm/s vs (42±13) cm/s, P<0.01, HBP(43% vs 58%, P<0.05), early recurrence(27% vs 48%, P<0.01),electrical cardioversion(2% vs 18%, P<0.01),LAD(41± 4) mm vs (44±4) mm, P<0.01, left atrial appendage orifice(LAA-O) (15.6±2.1) mm vs (16.4±2.6) mm, P<0.05 and left atrial appendage depth(LAA-D)(23±3) mm vs (24±3) mm, P<0.05. Multivariate logistic regression analysis indicated that LAA-EV, LAD and electrical cardioversion were independent factors of 1-year maintenace of SR. ROC showed that the cutoff 47.5 cm/s of LAA-EV(AUC0.816, 95%CI 0.75-0.87, P<0.01) predicted 1-year maintenace of SR with sensitivity of 75.5% and specificity of 73.1%.

  CONCLUSION  LAA-EV is a powerful factor of SR maitenance. LAA-EV≥47.5 cm/s strongly predicts 1-year maintenace of SR in patients with successful CA of PAF.