Acute venous and arterial vascular occlusions – treatment

Arterial vascular occlusion

Acute arterial occlusion occurs when an artery (carrying oxygen-rich blood from the heart to the periphery) suddenly becomes blocked. The most common cause is thrombi (blood clots), which are either carried by the bloodstream from the heart or another part of the body as an embolus, or which form locally as a result of injury to the vessel wall, e.g. due to pre-existing calcium plaques. Rarer causes are so-called paradoxical embolisms (passage of a blood clot from the venous system into the arterial system through a congenital hole in the cardiac septum), congenital coagulation disorders, cancer, etc.

In most cases, an embolus originates in the heart with pre-existing atrial fibrillation. This can then occlude any peripheral vessel, from the cerebral artery (with the risk of stroke) to the intestinal arteries (with the risk of reduced intestinal supply and death of parts of the intestine) and the arm or leg arteries (with the risk of amputation). Local thrombi can also form in any of these arteries.

Time is an important factor in acute vascular occlusion, because the longer the dependent tissue does not have sufficient blood flow, the higher the risk of irreversible damage.

Treatment options for arterial vascular occlusion

There are open surgical and percutaneous interventional treatment options:

Open surgical procedures include the so-called Fogarty thrombectomy, which is used in particular for occlusions of the arm and leg arteries. This requires general anesthesia with open exposure of an easily accessible vessel (usually the inguinal artery). The vessel is then opened with an incision and a Fogarty catheter (named after the first author) is inserted into the vessel with passage of the occluded section. This catheter has a balloon at the front end, which can be filled using a syringe at the back end. As soon as the catheter has been pushed past the thrombus, the balloon is filled and withdrawn together with the blood clot. A contrast agent and X-rays are then used to check whether any other blood clots remain in the vessel.

An alternative to this are various interventional techniques. A needle is inserted through the skin into an easily accessible vessel and wires or catheters are inserted into the vessel. A local anesthetic is usually sufficient for this. The blood clot can then be aspirated (aspiration thrombectomy) or dissolved by a drug that flows into the vessel for several hours (lysis).

Which strategy is used for you will then be determined by the attending physician. This depends, among other things, on your general condition and the location of the occlusion.

Preparation and aftercare

As this is a sudden illness, you as a patient cannot usually prepare for it.

After treatment of the vascular occlusion, you will receive blood-thinning medication at our hospital. In addition, the source of the embolus (if it was not a localized event) is sought. This may require an ultrasound examination of the heart, a determination of blood parameters or a computer tomography and other examinations. Depending on this, further therapy will then be discussed with you. If you are diagnosed with atrial fibrillation (the most common cause), it is usually necessary to continue blood-thinning therapy. It is important to clarify the cause in order to prevent new acute vascular occlusions.

Venous vascular occlusion

Occlusion of a vein (transport of deoxygenated blood from the periphery to the heart) is usually less dramatic than an acute arterial vascular occlusion. Venous vascular occlusion can be caused by one of the following factors or by a combination of factors: reduced blood flow properties (viscosity), slower blood flow velocity, damage to the vessel wall.

The most common localization of venous vascular occlusions is the leg arteries, but in principle any vein in the body can be affected. If a superficial vein is affected (which can sometimes be accompanied by a local inflammatory reaction), this is referred to as thrombophlebitis. Occlusions of deep veins, so-called truncal veins, are referred to as deep vein thrombosis (DVT).

Venous occlusion of leg arteries leads to destruction of the venous valves, which are important for maintaining the flow of blood back to the heart. As a result, leg vein occlusions can lead to a long-term backlog of venous blood in the leg and thus to the development of varicose veins. This is referred to as chronic venous insufficiency.

In addition to the typical examination findings, an ultrasound examination is important for the diagnosis of venous occlusions.

Thrombophlebitis

In most cases, thrombophlebitis is treated conservatively and, depending on which vein is involved, involves local treatment with a heparin ointment or heparin injections into the subcutaneous fatty tissue as well as elevation of the arm/leg and compression therapy with wrapping. In the case of leg veins, a compression stocking is also fitted. If there is an accompanying inflammatory reaction, cooling compresses, antibiotic therapy and painkillers can help.

In the majority of cases, DVT is also treated with several months of blood thinning therapy with tablets, the duration of which depends on the localization. In addition, compression therapy is started with compresses and then continued for several weeks to months. To check that the blood clot is not growing, the venous system is examined again a few days later using ultrasound. You can move normally again with this therapy.

An alternative to the conservative procedure is open surgery or percutaneous interventional reopening of the vessel. However, this is usually only recommended for pelvic veins with severe symptoms caused by blood backing up into the leg.

Open surgical treatment involves general anesthesia with visualization of the inguinal vein and removal of the clot using the Fogarty catheter described above. To prevent a direct re-occlusion, an artificial cross-connection between the inguinal artery and vein (arterio-venous fistula) is usually created for a period of three months in order to increase the pressure in the venous system. After three months, this is then surgically closed again.

Percutaneous interventional procedures are usually performed under local anesthesia and, as with arterial vascular occlusions, usually involve aspiration of the clot. In order to keep the vessel open, a stent (vessel support) is usually also inserted.

Precaution

To reduce the risk of venous vascular occlusion, you should drink plenty of fluids, especially at high temperatures, and move your legs regularly by exercising your muscles during long periods of sitting or standing.