Arterial and Aneurysm Management
Arterial Disease Management
Peripheral arterial disease is a common disorder of the blood vessels that supply blood to the legs and feet. It occurs because of atherosclerosis condition which is narrowing and hardening of the arteries caused by plaque buildup on the artery wall. The symptoms of peripheral artery disease are pain, tiredness and discomfort or burning sensation in the feet, calf or thigh muscles. Pain may aggravate during exercise or walking and get better on taking rest.
The decreased blood circulation to the legs may result in pain and loss of tissue which makes interventional treatment necessary to resolve the problem. Minimally invasive procedure involves endovascular treatment of the blocked blood vessel which is performed to treat peripheral arterial disease. Endovascular treatment is considered if all the conservative treatment methods have been unsuccessful.
During endovascular procedure, a thin, long tube called catheter is passed into your artery through a small incision made in the groin. The catheter is then advanced to the blocked area in the artery. Your surgeon then performs endovascular treatment such as percutaneous transluminal angioplasty and stenting.
In angioplasty procedure, a guide wire is passed through the catheter over which another catheter having a small deflated balloon at its end is passed to the area of blockage. The balloon is then inflated so that it compresses the plaque against the artery wall so as to open up the blood vessel and restore blood flow.
A stent or a small metal mesh tube may be placed in the artery at the time when the balloon catheter is placed to support the cleared vessel and to keep it open.
This is minimally invasive procedure that is performed within the blood vessels and requires only a small skin incision. This approach involves shorter recovery period of 2 weeks and allows the patient to return to work faster.
Endovascular Treatment for Aneurysms
Endovascular treatment is a minimally invasive procedure performed to treat conditions affecting the blood vessels and access to the affected area will be gained from within the blood vessels. Aneurysm is one such condition that can be treated with endovascular repair. Aneurysm is a bulge or a sac that develops on the arteries because of weakened blood vessel wall. There are two major types of aneurysms–intracranial or cerebral aneurysm which develop inside the brain and aortic aneurysm which develops inside aorta, the major blood vessel that carry oxygen-rich blood from heart to other body parts.
Intracranial aneurysm compresses the surrounding nerves and tissues causing pain, weakness, numbness, and paralysis on one side of the face. If aneurysm is left untreated, it may grow and become so thin that it ruptures resulting in subarachnoid hemorrhage, (leakage of blood into the space subarachnoid space) around the brain and may even cause death. If the aneurysm ruptures, you may experience severe head ache, double vision, nausea, vomiting, stiff neck, and/or loss of consciousness. Unruptured aneurysms does not cause any symptoms and are often detected accidentally during diagnosis of other conditions. Special X-ray scans, MRI and CT are performed to locate the intracranial aneurysms.
The two common options available for treatment of intracranial aneurysm are clipping and coil embolisation or endovascular coiling.
Embolisation: In embolisation method, embolic agents are used to block one or more blood vessels that are causing abnormalities or the aneurysm itself. Some of the embolic agents used for embolisation procedure include:
- Gelatin sponge material – The soft gelatin sponge is cut into small pieces and injected into the artery. Gelatin travels down the artery until it cannot go further. The surface of this material is highly porous that absorbs the liquid, forms a plug and occludes the arteries. However the occlusion remains for few days or weeks and then the material dissolves
- Gelling agents – These are suspended in liquid and injected into bloodstream which will block the blood vessels permanently
- Coils – These are the thin and long coils made of platinum or stainless steel. The coils are guided into the aneurysm using catheters. These coils block the flow of blood into the aneurysms
- Liquid sclerosing agents – Sclerosing agents are the detergents that irritate the lining of blood vessels, cause inflammation, swelling and finally stick together. This forms a scar tissue which disappears over the time. The sclerosing agents are injected into the abnormal blood vessel and the blood vessels are destroyed
- Liquid glue – The glue hardens immediately after insertion into the target site resulting in blockade of the artery and the blood flow into the aneurysm
Coil Embolisation: Coil embolisation can be performed on ruptured and unruptured aneurysms. Embolisation procedure is done by inserting a small and a hollow catheter through an incision made in the groin area. A catheter is passed through the artery in the groin are into the brain blood vessels. Through the catheter a contrast dye is injected into the blood which makes the blood vessels visible on an X-ray monitor. Under the guidance of X-ray imaging the catheter will be advanced further to reach near to the aneurysm.
Another tiny or microcatheter is advanced through the first catheter which passes into the aneurysm. One or more soft platinum coils are passed through the catheter and are released into the aneurysms where they pack and block the blood flow into aneurysms.
Coils promote formation of blood clots thus preventing the blood to flow in the aneurysm. After this procedure, your doctor may inject a contrast dye to confirm the blood is not flowing into the aneurysm and also to assure the coils are placed appropriately into the aneurysms. As these coils are thin platinum wires they are visible on an X-ray and are flexible to fit inside the aneurysm.
Once the coils are delivered the catheter will be removed, incision will be closed and covered with dressing.
Depending on the size, shape and location of aneurysm, sometimes coil embolisation will be unable to perform. In cases where aneurysm is at the base of the skull or if the aneurysms are large, a detachable balloon occlusion procedure may be performed. It is done by advancing the deflated balloon to the site of abnormality and then inflating it. This balloon is placed below or near to the aneurysm which will permanently help in closing the parent artery. Before performing this procedure, a preliminary test, called balloon test occlusion may be done to check the effects of artery occlusion in patient.
Another method to treat very large aneurysms is coiling along with stents. Stent is a small metallic hollow mesh which is advanced through the catheter until the neck of the aneurysm. Using the microcatheter the coils are released into the aneurysm. Then the balloon inside the mesh will be inflated to expand the mesh which acts as a barrier between the aneurysm and blood vessel. Stents prevent the protrusion of any coil mass into the parent artery. Then the balloon inside the stent and the catheters are removed leaving the stent and coils in place.
Although embolisation effectively treats aneurysms it is associated with certain risks. However these risks and complications can be treated. Some of the risks include:
- Blood clots may form inside the coil, catheter, or in the vessels that can break loose and blocks the smaller artery leading to stroke
- Aneurysm may rupture when inserting the catheter, coils, or guidewires
- Narrowing of the artery or vasospasm because of subarachnoid haemorrhage
- Inappropriate placement of the coils – Some coils may extend into the artery and may narrow the parent artery
- Incomplete filling of coils in aneurysm cause regrowth of aneurysm
Abdominal Aortic Aneurysms
An abdominal aortic aneurysm is an aneurysm located in the abdominal aorta. The most common cause of aortic aneurysms is atherosclerosis.
Most patients with abdominal aortic aneurysm do not have any symptoms. Usually, when the aneurysm ruptures you may experience the following symptoms:
- Pain in the abdomen groin, back, legs or buttocks
- Nausea and vomiting
- Clammy, sweaty skin
- Loss of consciousness
- Rapid heart rate
Abdominal aortic aneurysm endovascular repair is usually recommended if conservative treatment measures have failed to relieve the symptoms or if there is a risk of rupture due to the size of the aneurysm.
During an endovascular repair procedure, the patient is placed lying on their back on an X-ray table. A tiny cut will be made over the insertion site in your groin and a small tube called a catheter will be inserted into the artery. With the help of X-ray imaging, the physician slowly advances the catheter to the site of the aneurysm. The catheter contains a stent graft made of fabric with metal stents. The stent graft helps to decrease pressure on the aneurysm site by directing blood through the graft.
After the procedure X-rays are taken to make sure the stent graft is in place and no blood is leaking. The graft is expanded and held in place against the artery wall using small hooks or pins. The catheter will be removed and the incision in your groin will be closed.