Aortic Dissections
Art & Research: Kadir Özler
Further Reading Literature: Kadir Özler
Reviewed by Expert: Dr. Aaron Gindea (Cardiology)
The Aorta
The Aorta is a very important artery in the heart. It is where the oxygenated blood moves into before moving to the rest of the entire body. There are many "lanes" of the aorta that allow it to move to each part of the body such as the arms, legs, brain, etc.
Blood Flow out of the Aorta
To model how blood flows out of the Aorta, we can depict is a garden hose with three top lanes and one lane moving to the bottom of the body, although, of course, this is a simplification.
Two major sections of the Aorta are the Ascending Aorta (including the branches that go to the upper body including the brain) and the Descending Aorta (the portion that moves towards the lower body). Aortic Dissections can occur in any part of the Aorta, and can be potentially fatal if they enlarge too much and burst (UT Southwestern Medical Center).
Cross-section of the Aorta
There are three layers of the Aorta including the inner (intima), middle (media), and outer (adventitia) layers (UT Southwestern Medical Center).
Going with our garden hose analogy, we can model the middle and outer layers to be like the walls of a hose, allowing for compliance (or expandability) as blood moves through.
Blood Vessels and Pressure
The pressure within the Aorta with each heart beat is very large because such pressure is required for the blood to reach each distant location of the body. If the Aorta was stiff, then the vessel would be more likely to burst.
Thus, when a large pressure passes through it (blood flow with each heart beat), it can give slightly to allow the movement of this blood (Science Daily).
Age and Vessel Compliance
Unfortunately, the ability of the aorta to expand when blood moves through diminishes, creating a stiffer blood vessel as we age. This is true for other vessels in our bodies as well.
"Cracks" Emerge
When the Aortic wall becomes stiffer in a certain area, it is like a cracked wall that is vulnerable to further breaking and leaking of blood into the space between the inner and outer layers.
The high pressure doesn't help this situation, and if the Aortic wall weakens to the point where blood can pass through, then the middle layer of this vessel becomes filled with blood. This leads to the situation known as the "dissection," and this often leads to a sensation of ripping in the chest as the Aorta enlarges (Mayo Clinic).
Bursting
If the engorged middle layer of the Aorta expands too much, extreme pressure can be put on the outermost layer of the vessel. With too much pressure, bursting of the outermost layer can occur.
This can lead to a life-threatening situation because the leakage of blood from the ruptured location can cause large losses of blood. Extensive blood loss through this leak can lead to decreased blood entering other parts of the body, preventing those areas from getting enough oxygen to survive.
Important Organs & MORTALITY
If a dissection occurs and cuts off blood supply to important organs like the brain, this disease can be fatal to the patient.
Thus, it is recommended to see a doctor to look at the current size of a dissection and suggest possible treatments, like surgery, to repair the vessel (Mayo Clinic).