Assessment Of Left Atrial Function Using Echocardiography In Patients With Paroxysmal Atrial Fibrillation After Different Strategy Of Catheter Ablation

Backgrounds Catheter ablation of atrial fibrillation is the highlight point in the treatment field of arrhythmia. For the improvement of electrophysiology technology, the ablation strategy changed from segmental pulmonary vein isolation(SPVI) to circumferential ablation of pulmonary vein ostia(CPVA). The effect of ablation on left atrial function is still unclear now. There are few figure on the results after the two different strategy of catheter ablation. In this manuscript, we observe the changing of left atrial size and function using Echocardiography in patients with paroxysmal atrial fibrillation(PAF) before and after the two different strategy of catheter ablation to explore the impact of ablation on left atrial function.Objective To evaluate the effects of different strategy of catheter ablation on left atrial (LA) function in patients with PAF after long-term follow-up.Methods Sixty-five consecutive patients with PAF were treated by SPVI or CPVA(n=27,38,respectively). The mean follow-up duration was 14.9±5.5 month(range,6 to 27 months). LA dimensions and systolic function were evaluated before ablation and after long-term follow-up. In the late systole LA anteroposterior dimension(LAAPD) was examined by M-mode echocardiography, LA inferosuperior dimension(LASID) and LA mediolateral dimension(LAMD) were examined by 2-dimensional echocardiography from apical 4-chamber(A4C) view. Mitral inflow was recorded by pulsed-wave Doppler with the sample volume placed at the tip of the mitral leaflets. Early (V_E) and late (V_A) diastolic peak velocity and their velocity-time integral(E-VTI and A-VTI) were measured from the A4C view, to enable calculation of the E/A ratio,LA filling fraction(AFF) and LA ejection force(AEF).Quantity tissue velocity imaging(QTVI) measurements of mitral annulus motion were performed in the A4C,A2C,A3C view, with the sample volume placed at the two sides of the mitral annulus near LA. The average late (Va) diastolic peak velocity was recorded.Results①Eighteen patients(66.7%)out of twenty-seven in SPVI group were successfully ablated, and twenty-eight (73.7%) patients out of thirty-eight in CPVA group.②In the two successfully ablated groups, LA dimensions were similar before and after ablation. In each group LA dimensions decreased after long-term follow-up(SPVI,P<0.05, CPVA,P< 0.01,respectively).③The pulsed-Doppler parameters were similar in the two successfully ablated groups, but different in each group. Compelled with those before ablation, V_A and A-VTI increased in both groups(P<0.05), AFF increased only in SPVI group (P<0.05), with no difference in CPVA group, AEF was similar in both groups. It suggested that the global LA systolic function recovered and improved. The QTVI parameter Va was lower in CPVA group then that in SPVI group, which suggested that the regional LA systolic function was more impaired in CPVA group.Conclusion Catheter ablation for PAF is safe and effective. The LA structural remodeling reversed and global systolic function improved in the two successfully ablated groups after long-term follow-up, although the regional LA systolic function was more impaired in CPVA group then that in SPVI group probably as the result of more ablation lesions.