Association of left atrial fibrosis with aortic excess pressure and white matter lesions.

Objectives. Left atrial fibrosis represents a substrate for atrial fibrillation (AF) and cardioembolic events. White matter hyperintensities (WMH) are commonly found on magnetic resonance imaging (MRI) and are regarded, at least partly as ischemic brain lesions. Aortic excess pressure (excessPTI) represents an extra work performed by the left ventricle and is a new risk metric associated with cardiovascular complications. The aim of our study was to assessed whether there is a correlation between the degree of LA fibrosis, aortic excess pressure, and WMH in patients without a history of atrial fibrillation but the presence of risk factors for cardiovascular complications. Design. Thirty-eight subjects (10, females, 28 males, median age 64 years) with risk factors (hypertension, diabetes, heart failure, vascular disease) but no history of AF were recruited. Left atrial fibrosis and brain WMH were estimated by MRI. Aortic excess pressure was obtained non-invasively. Results. Atrial fibrosis correlated significantly with aortic excess pressure (r = 0.65, p < .0001) and was significantly associated with periventricular white matter lesion volume (r = 0.34, p = .036). In multiple regression analysis, atrial fibrosis and age were positively associated with periventricular white matter lesions, while aortic excess pressure was not quite significant associated with WMH. This model explains the 30% variance in white matter lesions volume observed in the study. Left atrial fibrosis was independently associated with excessPTI but not with age and mean BP. This model explained 42% of the variance in an area of atrial fibrosis. Conclusions. Atrial fibrosis in subjects with cardiovascular risk factors and no history of AF is associated with white matter hyperintensities and aortic excess pressure.