Abstract
Funding Acknowledgements
Type of funding sources: None.
Background
Left atrial (LA) function assessed by 2D speckle tracking echocardiography (STE) has demonstrated to be a useful predictor of recurrence of atrial fibrillation (AF) following catheter ablation (CA). Pulmonary vein reconduction (PVR) is one of the most important causes of recurrent paroxysmal AF (PAF) after ablation. The purpose of this study was to evaluate the association between AF burden (% of time in AF) following CA and LA strain measurements independently of PVR.
Methods
This prospective study included 66 patients with PAF who underwent CA (mean age 60 ± 8 years, 65% male). STE was performed during sinus rhythm prior to CA. AF burden was recorded by continuous rhythm monitoring using implantable loop recorders during a follow-up period of 4-6 months, excluding a blanking period of 3 months. After follow-up, all patients underwent an invasive assessment of pulmonary vein isolation to test for PVR. Multivariable linear regression analysis was used to assess the association between AF burden and peak atrial longitudinal reservoir strain (PALS), peak atrial contraction strain (PACS) and peak atrial conduit strain (PCS).
Results
Prior to CA, median AF burden was 3.8% (IQR: 0.5, 17). During follow-up, 37 patients (56%) were free of AF while median AF burden was 0.7% (IQR: 0.2, 1.6) in patients with an AF burden of more than 0%. A total of 35 patients (54%) were found to have PVR after ablation. Patients with AF recurrence had significantly lower PACS compared to patients with no AF during follow-up (10% ± 6% vs. 14% ± 5%, p = 0.004). No differences in PALS and PCS were observed. Increased PACS remained independently associated with low AF burden following CA after multivariable adjustments for clinical characteristics, comorbidities, and PVR (β=-0.262, p = 0.049) (Figure 1). PALS and PCS did not remain significantly associated with AF burden.
Conclusion
Increased PACS is strongly associated with low AF burden after CA even after adjusting for PVR. This suggests that an analysis of LA function could be useful to stratify patients prior to CA and improve treatment strategies.
Abstract Figure.
Left atrial function assessed by speckle tracking echocardiography predicts atrial fibrillation burden after catheter ablation independently of reconduction: a RACE-AF echocardiographic sub-study