CORRECTION for left ventricular diastolic function has rendered the association between atrial fibrillation (AF) and mortality insignificant, in patients with aortic stenosis. Dorien Laenens, Leiden University Medical Centre, the Netherlands, wrote, “in patients with severe aortic stenosis, atrial fibrillation is present in 15% and up to 50% in patients undergoing transcatheter aortic valve replacement.” Multiple studies have highlighted the prognostic value of AF in this patient bracket, with Laenens noting, “it is well known that significant aortic stenosis induces pressure overload, which leads to adverse left ventricular (LV) remodelling. An increased afterload is associated with LV hypertrophy, LV diastolic dysfunction, increased LV filling pressures. and subsequent left atrial dilation, which ultimately might cause AF.”
The current study evaluated data from a multicentre registry of 2,849 adult patients with significant aortic stenosis, defined as an aortic valve area of 1.5 cm or less. In a median follow-up of 60 months, 41.5% of patients had died. In comparison to patients with sinus rhythm, 10-year mortality was higher in patients with AF (46.8% versus 36.8%; log-rank p<0.001). Multivariable Cox regression analysis revealed that AF was an independent risk factor for all-cause mortality in patients with significant aortic stenosis (hazard ratio: 1.19; 95% confidence interval: 1.02–1.38; p=0.026), but this relationship was attenuated after correction for measures of LV diastolic function such as indexed left atrial volume and E/e’ (hazard ratio: 1.04; 95% confidence interval: 0.87–1.26; p=0.660).
The researchers noted that this large retrospective analysis of patients reveals that AF is not a prognostic marker once the population is adjusted for LV diastolic function, based on their findings that AF was not independently associated with outcomes. AF reflects underlying LV diastolic dysfunction and should raise awareness in the future for more pronounced adverse cardiac remodelling induced by significant aortic stenosis.
