Anatomical Profile of the Left Auricle on the Left Side of the Heart in Lateral Presentation

Description

Viewed in lateral presentation, the left auricle (auricula atrii sinistri) projects anteriorly and superiorly from the left atrium, forming a trabeculated appendage that overlaps the anterolateral contour of the left ventricle. Inferior to it, the left ventricle dominates the cardiac silhouette with a thick muscular wall, while the papillary muscles rise from the ventricular myocardium and tether the mitral valve leaflets via chordae tendineae. The atrioventricular groove separates the atrial appendage from the ventricular mass, with the apex positioned inferiorly and to the left. That spatial relationship matters in practice because the left atrial appendage is the common nidus for thrombus formation in atrial fibrillation, and its external contour guides percutaneous and surgical left atrial appendage occlusion. A lateral, section-oriented depiction also helps clarify how papillary muscle position and chordal tension maintain mitral competence, and why ischemia affecting the posteromedial papillary muscle can precipitate acute mitral regurgitation after inferior myocardial infarction. Small structures, big consequences. Use this artwork for teaching cardiac surface anatomy in gross anatomy and cardiothoracic surgery courses, and for illustrating discussions of left atrial appendage closure devices, mitral valve repair, and ventricular remodeling in cardiology texts or consent materials. Anatomical accuracy verified by SciePro's Medical Advisory Board.