S
Susan BAV
The Aorta, The Body's River of Life
By: BRADLEY J. FIKES - Staff Writer - North County Times
"From head to toes, fingers to nose, brain to bowel, the blood that keeps you alive leaves the heart through the aorta. The aorta is the largest artery in the body. It's the root of the Mississippi River of life, which spins off numerous branches, creeks and microscopic trickles.
Oxygenated blood from the lungs leaves the heart through the left ventricle, a large hollow chamber in the heart. When the heart muscle contracts, the left ventricle compresses the blood within. Blood squirts out an opening into the left ventricle into the aorta. The massive artery curves up around the middle of the heart and makes a left-hand turn before descending, getting smaller as branch arteries carry away parts of its flow. As it travels through the abdomen, the aorta becomes known as the abdominal aorta.
The aorta's critical role and physical characteristics are explained to a great degree by mechanics and hydraulics, not biology. When blood is expelled from the heart, it circulates under blood pressure to distant parts of the body. The aorta is elastic: It expands slightly under pressure and contracts when the pressure is lower, in the interval between heartbeats.
Hardening of the arteries, or atherosclerosis, robs the arteries of their elasticity. The arteries become brittle and weaker, somewhat like a rubber object left out in the elements. The walls of the arteries become roughened, making it easier for blood clots to form. And they can bulge out dangerously under pressure, like a weak spot in an inner tube. This is called an aneurysm.
An aortic aneurysm is by definition life-threatening, and the aorta is the most common place in the arteries for an aneurysm to form. That makes sense, because blood is under the greatest arterial pressure in the aorta. According to the Mayo Clinic, 15,000 people die of aortic aneurysms annually in the United States. However, the majority of aneurysms are small, grow slowly, and don't rupture.
Aneurysms sometimes make themselves known by causing back or abdominal pain. However, most of the time they do not cause symptoms. But they can be detected by tests such as ultrasound or MRI exams. When detected, they can be repaired, if sufficiently serious, by surgery. If they are minor, doctors may advise watching and waiting to avoid the risk of surgery.
Routine screening for aortic abdominal aneurysms (AAAs) would save lives, according to a September 2003 article in the Annals of Internal Medicine. Ruptures of these aneurysms are the 15th leading cause of death in the United States, the article pointed out. Only 20 percent of those who have such ruptures survive.
"On the other hand, screening would identify small AAAs unlikely to rupture in the patient's lifetime, but would cause worry and risk from unnecessary procedures. In the United States, physicians frequently repair AAAs smaller than 5.5 cm, and elective repair results in 1 in 6 AAA-related deaths," the article stated.
Keeping blood pressure within normal levels limits your risk from aneurysms, whether in the aorta or other critical parts of the body such as the brain, where they are called cerebral aneurysms. Lowered blood pressure may be achieved through reducing weight and exercise. In some cases, medication to lower blood pressure is needed."
By: BRADLEY J. FIKES - Staff Writer - North County Times
"From head to toes, fingers to nose, brain to bowel, the blood that keeps you alive leaves the heart through the aorta. The aorta is the largest artery in the body. It's the root of the Mississippi River of life, which spins off numerous branches, creeks and microscopic trickles.
Oxygenated blood from the lungs leaves the heart through the left ventricle, a large hollow chamber in the heart. When the heart muscle contracts, the left ventricle compresses the blood within. Blood squirts out an opening into the left ventricle into the aorta. The massive artery curves up around the middle of the heart and makes a left-hand turn before descending, getting smaller as branch arteries carry away parts of its flow. As it travels through the abdomen, the aorta becomes known as the abdominal aorta.
The aorta's critical role and physical characteristics are explained to a great degree by mechanics and hydraulics, not biology. When blood is expelled from the heart, it circulates under blood pressure to distant parts of the body. The aorta is elastic: It expands slightly under pressure and contracts when the pressure is lower, in the interval between heartbeats.
Hardening of the arteries, or atherosclerosis, robs the arteries of their elasticity. The arteries become brittle and weaker, somewhat like a rubber object left out in the elements. The walls of the arteries become roughened, making it easier for blood clots to form. And they can bulge out dangerously under pressure, like a weak spot in an inner tube. This is called an aneurysm.
An aortic aneurysm is by definition life-threatening, and the aorta is the most common place in the arteries for an aneurysm to form. That makes sense, because blood is under the greatest arterial pressure in the aorta. According to the Mayo Clinic, 15,000 people die of aortic aneurysms annually in the United States. However, the majority of aneurysms are small, grow slowly, and don't rupture.
Aneurysms sometimes make themselves known by causing back or abdominal pain. However, most of the time they do not cause symptoms. But they can be detected by tests such as ultrasound or MRI exams. When detected, they can be repaired, if sufficiently serious, by surgery. If they are minor, doctors may advise watching and waiting to avoid the risk of surgery.
Routine screening for aortic abdominal aneurysms (AAAs) would save lives, according to a September 2003 article in the Annals of Internal Medicine. Ruptures of these aneurysms are the 15th leading cause of death in the United States, the article pointed out. Only 20 percent of those who have such ruptures survive.
"On the other hand, screening would identify small AAAs unlikely to rupture in the patient's lifetime, but would cause worry and risk from unnecessary procedures. In the United States, physicians frequently repair AAAs smaller than 5.5 cm, and elective repair results in 1 in 6 AAA-related deaths," the article stated.
Keeping blood pressure within normal levels limits your risk from aneurysms, whether in the aorta or other critical parts of the body such as the brain, where they are called cerebral aneurysms. Lowered blood pressure may be achieved through reducing weight and exercise. In some cases, medication to lower blood pressure is needed."
