Morphological and secretory dysfunction of left atrium in Marfan syndrome

Abstract Introduction Marfan syndrome (MFS) is characterized by a mutation in the FBN1-gene which leads to a structural deficiency of the extracellular matrix component fibrillin-1 and a dysregulation of TGFβ. In recent years, cardiac remodeling with systolic and/or diastolic left ventricular dysfunction was shown in some MFS patients (Marfan Cardiomyopathy). Interestingly, in animal studies it has been shown that fibrillin-1 is abundantly present in atria and that TGFβ overexpression leads to atrial but not ventricular fibrosis (1, 2). However, the role of MFS for atrial remodeling and secretion (NT-proBNP) is unclear. Purpose To assess morphological and secretory function of the left atrium (LA) in patients with MFS and its relationship to left ventricular function. Methods We retrospectively analyzed echocardiographic and laboratory data in 307 Patients with MFS and in 147 healthy controls who had presented at our Marfan clinic between 23 February 2016 and 15 June 2020. At every visit, echocardiography had been carried out and NT-proBNP levels had been taken. A two-level mixed effects model was now performed to compare left atrial size between patients with MFS and controls. Results Left atrial size was significantly increased in patients with Marfan syndrome with and without aortic operation in medical history compared with controls (adjusted means: 18.4cm2 and 17.6cm2 vs. 15.5cm2 p