17. Atrial Fibrillation: Pathophysiology and Epidemiology: 17.2 Anatomical and Electrical Remodelling in Paroxysmal vs. Persistent Atrial Fibrillation

Abstract

Aim

to assess the relation between decremental interatrial conduction properties and atrial dilatation in patients (pts) with paroxysmal (p) vs persitent (P) atrial fibrillation (AF).

Methods

pts without structural heart disease and sustained AF episodes <1 month were included. Parameters: left atrial dimensions, surface (LAs), volume (LAv ellipse formula), right atrial surface (RAs), total atrial surface (TAs=LAs+RAs). To examine atrial electrophysiological properties it was calculated maximum percentage prolongation of interatrial conduction time (iaCT) during premature stimulation of high right atrium using S2 and S3 delivery: decremental index (DI) =iaCT S3-iaCTS1/iaCTS1%.

Results

27 pAFpts (53±9 years) were compared to 21 PAFpts (55±13 years). Following parameters were significantly higher in PAFpts: DI: 79±25% vs 51±19%, p<0.0001; LAl: 5.5±0.3 vs 5.2±0.3cm, p = 0.01; LAs: 23.5±3.1 vs 19.5±2.4cm ² , p = 0.001; LAv: 59.2±9.3 vs 53.6±10.4 ml, p = 0.001; TAs: 41.6±5.1 vs 35.6±6.9 cm ² , p = 0.0001. The simple regression analysis demonstrated a moderate correlation between TAs and DI (r = 0,66, r ² =0.44, p<0.0001), LAv and DI (r=0,6 r ² =0.36, p<0.0001).

Conclusion

This study demonstrates increased atrial stretch in PAFpts compared to pAFpts and that electrical remodelling is associated with anatomic remodelling.