Moguls of the heart

The 'moguls of the heart' refer to the bulges of the cardiomediastinal contour on frontal chest radiographs. The cardiomediastinal bulges are likened to skiing moguls (bumps of packed snow on a mountainside sculptured by turning skis). Awareness of their usual locations and etiologies is helpful in their recognition. 

Radiographic features

On the right cardiomediastinal border:

• the right atrium is the only normal bulge

On the left cardiomediastinal border:

• first mogul
  • uppermost, located paratracheally above the carina, and formed by the aortic arch (aortic knob)
  • prominence may be due to ectasia, aneurysm, or hypertension
  • notching or a "figure 3" sign suggests coarctation of the aorta
• second mogul
  • located just above the left main bronchus and represents the main pulmonary artery segment
  • excessive convexity is seen in poststenotic dilatation, pulmonary arterial hypertension, significant left-to-right shunts and pericardial defects
  • concavity suggests right-to-left shunts, pulmonary atresia, or malposed great vessels
• third mogul
  • never normal
  • if present, it lies below the left main bronchus and is usually formed by a prominent left atrial appendage, which is commonly seen in rheumatic heart disease
  • other causes include cardiac aneurysm, pericardial cyst, coronary artery aneurysm, mediastinal tumor, pericardial defect, sinus of Valsalva aneurysm, and dilated right ventricular outflow tract
• fourth mogul
  • bulge just above the diaphragm formed by the left ventricular margin or cardiac apex
• fifth mogul
  • bulge at the cardiophrenic angle
  • may be caused by prominent pericardial fat pad, pericardial cyst, or adenopathy

History and etymology

The term was popularized by M Daves in the 1970s ^1-3.