Popliteal Artery Aneurysm

An abnormal bulge that occurs in the wall of the artery that runs through the area behind the knee is called a popliteal artery aneurysm. The popliteal artery, which is also the peripheral artery, is the most commonly affected aneurysmal degeneration. The term “aneurysm” indicates a weak area of the artery that bulges or expands to reach over one and a half times its normal diameter. When talking about the popliteal artery aneurysm then, it can be defined as a popliteal artery diameter that is in excess of two centimeters. The wall of the aneurysm will continue to be weak and the size of the aneurysm will continue to grow.

A popliteal artery is located behind the knee, so there are chances of an aneurysm occurring in this location. It is the main artery that supplies the leg with blood, which passes behind the knee. It is very rare for a patient to show any signs or symptoms of an aneurysm. The symptoms are mostly discovered during a routine check-up or when checking for some other medical condition. A popliteal artery aneurysm is known to occur in both legs about fifty percent of the time. It can occur in both men and women. Many patients who suffer from a popliteal artery aneurysm also have another medical condition called abdominal aortic aneurysm.

If the doctor suspects a popliteal artery aneurysm, an ultrasound may be suggested to check for its presence. This test will also help determine its size, as well as look for any presence of a blood clot along with the aneurysm. It is possible that a blood clot will form along the inside wall of the aneurysm. This would happen due to abnormal swirling of blood within the sac. The main problem arises when the blood clot builds up to the point where it causes a complete shutdown of the blood flow. This shutdown happens because some of the clot within the aneurysm goes down the artery towards the foot. When such an event occurs, it can lead to the amputation of the leg and foot. This is why this type of medical condition is dangerous. The popliteal artery aneurysm rarely ruptures, but occasionally it can happen.

Most people with popliteal artery aneurysm do not have any symptoms, but often, the symptoms include:

• Pain behind the knee
• Foot pain
• An edema (collection of watery fluid) in the lower leg
• Ulcers on the skin of the feet that don’t heal
• Reduction in circulation, which can occur gradually or on a chronic basis
• Acute ischaemia along with severe pain in the onset of the foot

Formation of clots is quite common on the luminal lining of the artery wall in the aneurysmal area. This clot can later disperse into the smaller run off arteries of the limb and completely block them. This may cause the blood flow to the foot to be significantly impacted and reduced, thus threatening its viability. 

There is no known cause of a popliteal artery aneurysm. Atherosclerosis (the hardening of the arteries due to fluid build-up of fatty substances) is believed to be related to popliteal artery aneurysms.

Popliteal artery aneurysms are mostly associated with atheromatous degeneration of the arterial wall. This is commonly seen in men and those above the age of sixty. Smoking and tobacco intake are also factors for developing a popliteal aneurysm. Apart from these, other causes of this medical condition include Marfan and Ehlers Danlos syndrome, wherein other anomalies coexist, and popliteal artery entrapment, which would lead to poststenotic aneurysm formation.

To diagnose popliteal artery aneurysm, a doctor will conduct tests such as:

• Ultrasound: This measures the blood flow in the aortic artery through the use of sound waves. It is one of the common tests performed to diagnose a popliteal aneurysm and is a painless examination. One would lie on the back on an examination table, and a small amount of warm gel would be applied to the abdomen. This gel helps to eliminate any formation of air pockets between the body and the instrument, which is used to see the aorta. This machine is called a transducer.
• CT scan: X-ray views of the aortic artery check for an aneurysm. This is a painless examination that can provide the doctor better and clearer images of the aortic artery, thus helping to detect the shape and size. To perform the CT scan, one would need to lie on a table inside a machine. The CT scan generates X-rays to produce cross-sectional images of the body. The doctor can inject a dye into the blood vessels to make it more visible.

• MRI: This shows the areas where an aneurysm might be present through magnetic fields and radio waves. An MRI is a painless procedure that can diagnose this medical condition and at the same time determine its location and size. To conduct this test, the patient would lie on a table, which is movable and slides into a tunnel. The MRI uses the magnetic pulses of radio wave energy to make pictures of the body. The doctor can inject dye into the blood vessels to make them more visible.
• Angiography: A dye is inserted into the arteries via a catheter. An angiography can directly show the mural calcification. In about thirty percent of cases, the conventional angiography does not demonstrate aneurysmal dilation due to the formation of the thrombus within the sac of the aneurysmal; it instead appears as an acute bend in the course.

The treatment for a popliteal artery aneurysm is surgery. The surgeon will create a bypass around the artery where the aneurysm is found and will introduce medication to reduce the risk of high blood pressure.

Once the popliteal artery aneurysm is confirmed, the doctor will decide whether or not to repair it at that time. It is ultimately the doctor’s choice whether to repair it or to keep a close follow-up and observation. There are multiple issues that have to be considered, including the size of the aneurysm, the presence or absence of a blood clot within the aneurysm, the condition of the arteries both above and below the aneurysm, and lastly, but most importantly, the overall health of the individual.

Repairing using the surgical method is usually quite successful and durable. But this surgical process has to be performed with a minimal amount of risk. One of the best repair procedures involves an incision on the leg, after which the popliteal artery aneurysm is removed, then reconstruction of the flow of blood to the foot using either a vein or an artificial artery. Within a couple of years, doctors recommend stent grafts to get the popliteal artery aneurysm repaired. This is usually considered for patients who are not good candidates for the standard surgical repair.

The general consensus is that if the aneurysm is causing symptoms and is greater than two centimeters in diameter, it should be treated. There are two method of repair which depend mainly on the anatomic and morphological features of the aneurysm. Presently, the techniques are open repair and endovascular treatment.

There is no prevention for a popliteal artery aneurysm, because its cause is still unknown.

Some of the homeopathic remedies for popliteal artery aneurysms include: 

• Aconite napellus
• Belladonna
• Calcarea Carbonica
• Lycopodium

These alternative medicines should only be taken with professional advice.

You can adopt the following lifestyle measures to decrease your risk of a popliteal artery aneurysm:

• Control blood pressure and cholesterol
• Avoid smoking
• Consult your doctor if you have the signs and symptoms of a popliteal artery aneurysm
• Exercise on a regular basis, or at least carry out brisk walking for thirty to forty-five minutes a day
• Maintain an ideal body weight to avoid any accumulation of unwanted substances in the body
• Make dietary changes to limit the intake of animal fat and foods that contain high calories and cholesterol

You are at risk of a popliteal artery aneurysm if:

• You have high blood pressure and high cholesterol
• You have a bacterial infection
• You smoke
• There is blood vessel reconstruction in one or both legs