Arterial thrombosis is a blood clot that develops in an artery. It's very dangerous, because it can obstruct the flow of blood to major organs.

Depending on where the clot forms, arterial thrombosis can cause several serious conditions, including:

• heart attack – when blood flow to the heart is suddenly blocked 
• stroke – when blood flow to the brain is cut off 
• peripheral arterial disease (PAD), also known as peripheral vascular disease (PVD) – when a build-up of fatty deposits in the arteries restricts the blood supply to leg muscles

Heart attack and stroke are two of the leading causes of death in the UK.

Who's at risk?

Most cases of arterial thrombosis are caused when an artery is damaged by atherosclerosis. This is where fatty deposits called plaque build up on the walls of the arteries, causing them to harden and narrow. If the plaque ruptures (bursts), a blood clot may develop.

Your risk of developing an arterial blood clot is increased if you:

• eat a high-fat diet
• smoke
• drink more units of alcohol than the recommended amount (men shouldn't regularly drink more than 3-4 units a day and women shouldn't regularly drink more than 2-3 units a day)
• are obese
• don't do regular exercise
• have diabetes (either type 1 diabetes or type 2 diabetes)
• have high blood pressure (hypertension)
• have high cholesterol

The risk of arterial thrombosis also increases with age, so older people are more commonly affected.

Treating arterial thrombosis

It's sometimes possible to treat arterial thrombosis with medication or surgery.

Medication

In some cases, a type of medication called a thrombolytic can be used to dissolve blood clots and restore the blood flow in an artery. Examples of thrombolytic medicines include alteplase and reteplase.

These medicines are most effective if they're used as soon as possible after a heart attack or stroke starts.

Surgery

Surgery for arterial thrombosis involves unblocking the affected artery or re-routing the flow of blood around the blockage. The type of surgery used will depend on the location and severity of your condition.

For example, you may need heart surgery if the blood clot is in an artery that supplies blood to your heart. Operations used to treat this include:

• coronary stent placement – where a balloon is inflated in a blocked artery (angioplasty) to allow a hollow metal tube called a stent to be used to widen the artery and stop it from becoming blocked again
• coronary artery bypass graft – where a blood vessel taken from another part of the body is used to bypass the point of the blockage

If you have a blood clot in your neck, you may have a type of surgery called carotid endarterectomy. During this operation, the surgeon makes a cut in your neck to open up the artery and remove the fatty deposits.

Reducing your risk

It isn't possible to entirely prevent blood clots from forming, but there are numerous ways you can minimise your risk.

Medication

If you've previously had a blood clot, you may need to take medicines to reduce the risk of it happening again. These include:

• statins to lower your blood cholesterol levels 
• anticoagulant medicines – such as warfarin, sinthrone, dabigatran, apixiban, rivaroxaban, or antiplatelet medicines, such as low-dose aspirin or clopidogrel, to thin the blood and reduce the risk of clotting
• antihypertensive medicines to reduce high blood pressure – such as angiotensin-converting enzyme (ACE) inhibitors

Lifestyle

You can also reduce your risk of developing arterial thrombosis and heart disease by:

• not smoking
• reducing the amount of salt you eat
• cutting down on fat (particularly saturated fat)
• eating at least five portions of fruit and vegetables a day
• doing a minimum of 150 minutes (2 hours 30 minutes) of moderate-intensity exercise a week, such as fast walking, cycling or water aerobics (read more about the physical activity guidelines for adults)