Over 70% of aortic dissections happen in the portion of the aorta just above the heart, known as the ascending aorta. These dissections are known as Stanford A or BeBakey I/ II dissections. Due to the continuous pumping action of the heart, the false lumen expands and widens over time, causing significant weakening of the aortic wall, with high probability of bursting (an “aneurysm”). Because the immediate threat to the patient’s life is the bursting of the ascending aorta, this portion of the aorta is generally what is focused on during the initial emergency repair while the dissection and false lumen beyond the ascending aorta often causes other serious conditions such as chronic aneurysms and ruptures, strokes, and obstruction of flow to the abdominal organs and the lower extremities. Because of technical difficulties and the extremely serious condition of the patients at the time of their dissection, the surgeons are focused on removing the ascending aorta as quickly as possible and leave the remainder of the disease beyond the ascending aorta. Today even after “successful” initial emergency repair, over 75% of the patients are left with a residual tear in the arch (the curved portion of the aorta) and the remainder of the aorta that degenerates into difficult-to-treat chronic dissections and aneurysms that are even more complicated than the first operation. Approximately 40% – 50% of these patients require additional high-risk aortic procedures and 50% die within 10 years.
The aorta is the artery that comes out of the top of the heart delivering oxygenated blood to the body. The aorta is like an upside down snorkel that comes out the top of the heart, does a u-turn (the “arch”) and delivers blood to the body. Sometimes, the inner-wall of the aorta develops a tear, and because of blood pumping, creates an alternate channel (known as a “false lumen.”) for the blood to follow. This condition is known as an “aortic dissection”. Because the wall of the aorta has been split into two layers, the aorta is weakened, which can cause it to burst, and the patient to bleed out. If the aorta bursts the patient dies quickly.