mogul sign

A sharply demarcated—suggestive of serosal covering (i.e., extrapulmonary)—margin seen in the left side of a plain chest film; the 3rd mogul is an abnormal protuberance located below the left mainstem bronchus and pulmonary artery corresponding to an enlarged or herniated left atrial appendage seen in rheumatic heart disease, pericardial defects, chordae tendineae or papillary muscle defects, left atrial tumours and cardiomyopathy; the left ventricle may be elevated in tetralogy of Fallot, Ebstein anomaly, or in a left-sided ascending aorta in corrected transposition of great vessels

mogul sign

Third mogul sign Radiology A sharply demarcated–suggestive of serosal covering–ie, extrapulmonary-margin seen in the left side of a plain CXR; the 3rd mogul is an abnormal protuberance located below the left mainstem bronchus and pulmonary artery corresponding to an enlarged or herniated left atrial appendage seen in rheumatic heart disease, pericardial defects, chordae tendineae or papillary muscle defects, left atrial tumors and cardiomyopathy; the left ventricle may be elevated in tetralogy of Fallot, Ebstein anomaly, or in a left-sided ascending aorta in corrected transposition of great vessels.