An ectatic abdominal aorta is a dilation or mild bulging of its abdominal segment, explains Cedars-Sinai. The aorta is the largest artery in the human body and extends from the heart, carrying oxygen-rich blood. The aorta descends through the abdomen and divides into vessels in each leg.
According to the U.S. Department of Health and Human Services, ectasia refers to arterial dilation that is less than 50 percent of the expected normal diameter. When a weak area of the aorta expands or bulges beyond 50 percent, it is considered an aneurysm. Thoracic aneurysms are serious health risks because they can rupture and cause severe internal bleeding, leading to shock or death, explains Cedars-Sinai.