The aorta is the major blood vessel that carries blood from the heart to the rest of the body. It is made up of three layers. These layers provide the integrity essential for the aorta to withstand the pressure of the blood pumped through it.

An aortic dissection occurs when there occurs a tear in the innermost layer – blood flows consequently between the layers of the aortic wall.

Aortic dissection occurs when the innermost layer of the aorta (intima) tears and blood flows between the layers of the aorta’s wall. Due to the dissection blood flows in two channels – a true lumen and a false lumen – blood supply to the various organs variably arises from these two channels and affects/ compromises organ function and survival.

Loss of the combined integrity of the three layers leads to the aorta immediately thinning out because of the dissection – with potential for rupture as an immediate complication or aneurysm formation and risk of rupture at a later date.

Aortic dissection tens to occur for many reasons:

Uncontrolled high blood pressure, genetics, due to trauma sustained in a motor vehicle accident or fall from a height, high cholesterols, old age with atherosclerosis, illicit drug use and in chronic smokers among other causes.

Certain genetic syndromes predispose to aortic dissection either due to a weak aortic wall or due to gradual enlargement of the aorta (aneurysm). Besides some patients are born with – a Bicuspid Aortic Valve (a condition where the aortic valve has 2 leaflets in lieu of the normal 3) – these patients are more prone to having an aneurysms of the ascending aorta and the aortic root – predisposing them to aortic dissections.

The dissection may involve any part of the aorta starting from just above the aortic valve to all the way down to the abdomen where the aorta divides into the blood vessels supplying the lower limbs.

The most common symptom experienced by patients who have an aortic dissection is severe, tearing pain in the chest or upper back.

Since the aorta is the major artery from where other vessels arise from some patients may have chest pain like heart attack – when the coronary arteries supplying the heart are affected. If the blood vessels supplying the brain are involved symptoms may be like that of a stoke viz. loss of consciousness, blackout, loss of power in the arms or legs or slurred speech. Some experience symptoms due to what is describes as ‘malperfusion’ – wherein blood to certain organs like the intestines – causing nausea and vomiting, kidneys (abnormalities on laboratory tests) and the arms and legs are affected (loss of power in the arms and legs and other symptoms like tingling and numbness).

Some patients have blood supply to the spinal cord affected leading to acute paraplegia (loss of power in the limbs) or in some cases shortness of breath when the aortic valve is involved in the aortic dissection.

• The decision to proceed with testing is made based on the clinical history and the physical findings on clinical exam.
• An urgent CT scan of the entire aorta is performed to arrive at a diagnosis and proceed with treatment planning.
• This is usually followed by an Echo and laboratory investigations.

The treatment of an aortic dissection depends on the part of the aorta involved.

Those involving the aortic root, ascending aorta are life-threatening, and time is of the essence to save one’s life due to the risk of complications like –rupture and bleeding, involvement of the coronary arteries and the aortic valve.

Surgery usually involves replacing the involved portion of the aorta with a tube graft and repair/ replacement of the aortic valve or re-implantation of the neck vessels in various combinations or in isolation depending on the pre-operative CT scan and intra-operative findings.

The dissection involving the aorta beyond the arch – descending thoracic aorta (where the vessels to the brain and upper limbs come from) are usually managed medically with intervention in certain situations.

Therapy would include strict blood pressure control, imaging and regular follow up to detect possible complications early.

Certain patients with descending thoracic aortic dissections may undergo Thoracic Endovascular Aortic Repair (TEVAR) wherein a stent graft made of fabric and supported by a wire framework is inserted into the true lumen od the dissection in order to seal the intimal tear.

This may be performed in emergent situations where malperfusion to the organs in the abdomen or the circulation to the lower limbs may be compromised among other indications.

Aortic aneurysm surgery is considered major surgery and it would be best to discuss the risks and the conduct of the operation in detail with the surgical team well in advance.

The post-operative course is largely guided by the pre-operative status and co-morbidities of the patient prior to surgery.

Even with surgery follow up is essential to diagnose complications and manage them early.

CT scans on follow up are essential at pre-determined intervals.

This follow up would include regular follow ups with the surgeon and cardiologist for strict control of blood pressure. Activities with severe physical exertion are to be avoided; smoking cessation is mandatory.