The left atrial appendage arrhythmogenic and thrombogenic substrate

The left atrial appendage arrhythmogenic and thrombogenic substrate The left atrial appendage (LAA) is a significant source of strokes in patients with atrial fibrillation (AF). Helena Dominguez from the Department of Cardiology at the University of Copenhagen discusses the LAACS studies, which investigate the effects of LAA exclusion during heart surgery. The left atrial appendage (LAA) is known as a feared cardioembolic source of strokes in patients with atrial fibrillation (AF). This has been attributed to a so-called atrial myopathy, where structural and functional changes in the LAA may render the LAA prone to form blood clots (Blume et al., 2011; Goette et al., 2016) and also prone to developing AF (Ma et al., 2017; Zhao et al., 2017). In this regard, considerable attention is focused on the development of fibrosis in the LAA, as it occurs more frequently in patients with AF compared to those without (Bertelsen et al., 2020; Marrouche et al., 2014; Miyauchi et al., 2022; Vasan et al., 2003). Additionally, thrombi have been found to be associated with fibrosis in the left atrial appendage (LAA) (Akoum et al., 2013; Miyauchi et al., 2022).