The conus artery is a coronary artery that is present in only 45 percent of human heart

Human heart

The human heart is a muscular organ that provides a continuous blood circulation through the cardiac cycle and is one of the most vital organs in the human body...

s. The conus artery may provide collateral blood flow to the heart when the left anterior descending artery is occluded. In one study, 305 cadaveric specimens were examined to determine the origin of the conus coronary artery. The authors found that the conus artery could arise independently from the aorta

Aorta

The aorta is the largest artery in the body, originating from the left ventricle of the heart and extending down to the abdomen, where it branches off into two smaller arteries...

 or from a common ostium

Ostium

Ostium may refer to:Anatomy*Ostium of Fallopian tube*Ostium primum or foramen ovale of the developing heart*Ostium maxillare of the maxillary sinus*Ostium of female lepidoptera genitalia...

 with the right coronary artery

Right coronary artery

The right coronary artery originates above the right cusp of the aortic valve. It travels down the right atrioventricular groove, towards the crux of the heart.At the origin of the RCA is the conus artery....

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