Atrial fibrillation in severe aortic valve stenosis - Association with left ventricular left atrial remodeling

Background: Atrial fibrillation (AF) is common in patients with aortic stenosis (AS) although the exact mechanism is unclear. The purpose of this study was to investigate echocardiographic characteristics among patients with severe AS and AF and to identify factors associated with the development of new-onset AF after aortic valve replacement (AVR). Methods: 125 patients with severe AS and ejection fraction > 40% scheduled for AVR were evaluated preoperatively and 3, 6, 9 and 12. months postoperatively with electrocardiography (ECG) and echocardiography, and Holter-ECG analysis was performed after 3 and 12. months. The primary endpoint was new-onset AF defined as an episode of AF exceeding 30. s, on the ECG or Holter-ECG and/or patients hospitalized due to AF. Results: AF was present in 19 patients prior to AVR, compared to patients in sinus rhythm AF patients had increased NT-proBNP, increased left atrial (LA) volume (61±21 vs. 47±17ml/m², p=0.002), reduced global longitudinal left ventricular strain (-13.1±3.7 vs. -16.0±3.5, p=0.002) and presented more often with a restrictive filling pattern (37% vs. 10%, p=0.002). During follow-up 23 patients developed new-onset AF; predictors were LA volume, restrictive filling pattern, NT-proBNP, E/e' and systolic blood pressure. After correcting for age and LA volume index, a restrictive filling pattern and systolic blood pressure remained associated with new-onset AF. Conclusions: The presence of preoperative AF and development of new-onset AF after AVR is associated with restrictive filling pattern and LA dilatation in patients with severe AS.