ABLATION

A medical technique performed to remove or “inactivate” a small part of the body.

ACQUIRED THROMBOPHILIA

Acquired thrombophilia is when you develop thrombophilia (a tendency to form abnormal clots) later in life rather than at birth.

ANTIBODY

A molecule produced by your body which specifically targets another molecule. Usually these are naturally produced by the immune system to protect you against bacteria and other foreign agents, but in autoimmune disorders they can target your own body to cause illness.

ANTICARDIOPILIN

One of three antibodies (see Antibody) produced in antiphospholipid syndrome (see Antiphospholipid syndrome) which can increase the risk of forming blood clots.

ANTICOAGULANTS

Medication also known as “blood thinners” which help to prevent the formation of blood clots. Common anticoagulants include Warfarin, Rivaroxaban, Apixaban, and Dabigatran.

ANTIPHOSPHOLIPID SYNDROME

An autoimmune disorder where the immune system mistakenly attacks and damages normal tissues and cells. This can cause damage to blood vessels that increase the risk of developing blood clots.

ANTITHROMBIN

One of the bodies natural anticoagulants. Antithrombin is a protein found naturally in the blood which prevents blood clots from forming. An antithrombin deficiency can cause an increased risk of blood clots and affects around 1 in every 2000 adults worldwide.

APIXABAN

A direct oral anticoagulant (DOAC) (see Direct oral anticoagulants) or medication used to prevent the formation of blood clots.

ARRYTHMIA

A medical condition where there is a problem with the rate or rhythm of the heartbeat. This can mean it beats too fast, slow, or in an irregular fashion.

ARTERIAL THROMBOEMBOLISM

A condition where an artery (blood vessel leading from the heart) is blocked by a blood clot that has travelled through the blood stream (see Thromboembolism).

ATHEROSCLEROSIS

A condition in which plaque (cholesterol, fats, and other substances) builds up on the walls of your arteries. This plaque can reduce the blood flow and cause further complications including blood clots.

ATHEROTHOMBOSIS

The formation of a blood clot (or thrombus) inside an artery.

ATRIAL FIBRILLATION

Atrial fibrillation (also known as AFib or AF) is a kind of arrythmia. In atrial fibrillation, the heart quivers (or “fibrillates” in medical terms). This prevents the heart from effectively pumping blood around your body and can cause blood to pool and blood clots to form.

AUTOIMMUNE DISORDER

A condition in which your body’s immune system attacks normal cells and tissue, causing disease.

BETA-2 GLYCOPROTEIN I

One of three antibodies (see Antibody) produced in antiphospholipid syndrome (see Antiphospholipid syndrome) which can increase the risk of forming blood clots.

CARDIOVERSION

A medical technique used to restore the heart’s natural heartbeat and rhythm. See Electrical cardioversion and Pharmacologic cardioversion.

CHRONIC ATRIAL FIBRILLATION

One of the three subtypes of atrial fibrillation. Chronic atrial fibrillation is when the irregular or “fluttering” heartbeat occurs all the time. Also known as permanent or sustained atrial fibrillation.

CLOTTING FACTORS

Clotting factors are natural proteins found in the blood which cause the blood to clot in the event of a cut or wound. This clot forms a “plug” which prevents excessive bleeding. This is called “haemostasis” (see Haemostasis).

COMBINED ORAL CONTRACEPTIVES (COCs)

Combined oral contraceptives (the birth control pill) is a birth control medication taken orally by women. COCs contain both synthetic oestrogen and progesterone. The combined oral contraceptive pill carries an increased risk of developing a venous thromboembolism (VTE).  

COMPRESSION STOCKINGS

Compression stockings, or graduated compression stockings, are a medical device worn on the leg that keep pressure on your legs. These are thought to decrease the risk of blood clots by increasing blood flow from the shallower blood vessels to the deeper blood vessels, thereby preventing blood from pooling.

CORONARY HEART DISEASE

A condition where the blood vessels that supply the heart with blood (coronary arteries) become damaged or diseased. This often involves the formation of fatty plaques on the walls of the arteries that limit blood flow. This condition is a risk factor for developing dangerous blood clots.  

DABIGATRAN

A direct oral anticoagulant (DOAC) (see Direct oral anticoagulants) or medication used to prevent the formation of blood clots.

DIRECT ORAL ANTICOAGULANTS (DOACs)

Medication also known as “blood thinners” which help to prevent the formation of blood clots. Common anticoagulants include Warfarin, Rivaroxaban, Apixaban, and Dabigatran.

DEEP VEIN THROMBOSIS (DVT)

A condition where a blood clot (or thrombus) has formed within the deep veins. This usually occurs in the veins of the leg or pelvis and can become dislodged (becoming an embolus) and travel through the blood stream. A DVT can result in further complications such as decreased blood flow, or lead to a pulmonary embolism (PE) (see Pulmonary embolism).

DVT

See Deep Vein Thrombosis.

DYSFIBRINOGENAEMIA

A condition in which the fibrinogen protein (see Fibrinogen) is dysfunctional. Fibrinogen usually controls bleeding by helping blood clots to form. In dysfibrinogenaemia the fibrinogen protein can cause increased bleeding, increased clotting, or both, which can lead to severe complications.

ELECTRICAL CARDIOVERSION

A medical technique used to treat atrial fibrillation in which an electric “shock” is applied to the heart in order to re-establish the normal rhythm of the heartbeat.

EMBOLISM

An embolism is when an embolus, or unattached blood clot, lodges in a vein or artery causing a blockage. An embolism may also be a fat globule or gas bubble. 

EMBOLUS

An embolus is a blood clot that has dislodged or broken free from a blood vessel and travels through the blood stream. These can result in severe complications such as stroke or pulmonary embolism (PE).

FACTOR V

Factor V is a molecule which helps the blood to clot. This is known as a “procoagulant”.

FACTOR V LEIDEN

The most common inherited thrombophilia (see Inherited thrombophilia). Factor V is a molecule which helps the blood to clot. In Factor V Leiden, the body finds it more difficult to stop Factor V from forming blood clots. This means that the clotting process goes on for longer and carries a higher risk of developing a dangerous blood clot.  

FIBRILLATE

A medical term which means “to quiver”, such as in atrial fibrillation where the atria (top chambers) of the heart quiver rather than beating effectively.

FIBRINOGEN

A protein in the blood which is converted to fibrin - another protein which causes blood to clot.

HAEMORRHAGIC STROKE

One of the types of stroke. A haemorrhagic stroke occurs when a blood vessel leading to the brain or inside it bursts, causing bleeding. The two kinds of haemorrhagic stroke include intracerebral haemorrhage (when an artery in the brain bursts) and subarachnoid haemorrhage (bleeding on the surface of the brain).

HAEMOSTASIS

Haemostasis is the first step in wound healing. It is the process that stops bleeding by causing a blood clot to form which “plugs up” the wound. Haemostasis involves coagulation of the blood and is important for normal bodily function.

HETEROZYGOUS

Every person has two copies of every gene as one copy is inherited from each parent. Heterozygous means that you have two different versions of a gene. In the case of certain diseases this means that one copy may be the dysfunctional or disease gene and may give you that disorder. For example, your mother is heterozygous for Factor V Leiden, meaning she has one copy of the normal functional gene, and one copy of the abnormal dysfunctional gene. Your father, however, is homozygous for the normal gene - meaning he has two copies of the normal gene. You might inherit the dysfunctional gene from your mother and the functional gene from your father - making you heterozygous for Factor V Leiden.

HOMOCYSTEINE

Homocysteine is an amino acid (part of a protein) that is found naturally in your blood. While homocysteine is a normal and healthy component of blood, high levels of homocysteine can cause damage to blood vessels – resulting in an increased risk of developing a dangerous blood clot.

HOMOCYSTINURIA

A rare and severe form of hyperhomocysteinaemia (see Hyperhomocysteinaemia) in which there is high levels of homocysteine in the blood.

HOMOZYGOUS

Every person has two copies of every gene as one copy is inherited from each parent. Homozygous means that you have two identical versions of a gene. In the case of certain diseases this means that both copies may be the dysfunctional or disease gene and may give you that disorder (often if you are homozygous for a disease gene then it is more severe than if you are heterozygous). For example, your mother is heterozygous for Factor V Leiden, meaning she has one copy of the normal functional gene, and one copy of the abnormal dysfunctional gene. Your father, however, is homozygous for the abnormal gene - meaning he has two copies of the abnormal gene. You might inherit the dysfunctional gene from your mother and father - making you homozygous for Factor V Leiden.

HORMONE REPLACEMENT THERAPY (HRT)

A form of hormone therapy used to treat symptoms associated with female menopause. This may include the hormones oestrogen and progesterone.

HYPERCOAGULABILITY

The tendency to develop blood clots more than normal (see Thrombophilia). This may be due to inherited traits (such as Factor V Leiden) or acquired traits (such as medication include the combined oral contraceptive pill).

HYPERHOMOCYSTEINAEMIA

A condition in which there are unnaturally high levels of homocysteine in the blood (see Homocysteine). While homocysteine is a normal and healthy component of blood, high levels of homocysteine can cause damage to blood vessels – resulting in an increased risk of developing a dangerous blood clot.

HYPERTENSION

Also known as high blood pressure. A condition in which the blood pressure (force that the blood pushes against the walls of arteries) is too high and can cause complications. Hypertension can increase the risk of heart disease and stroke.

INHERITED THROMBOPHILIA

Thrombophilia is an abnormal state where the blood is more likely to clot. Inherited thrombophilia (also known as genetic thrombophilia) is a condition some people are born with that increases their risk of developing dangerous blood clots.

ISCHAEMIC STROKE

One of the types of stroke. An ischaemic stroke occurs when a sudden blockage in the arteries leading to the brain prevents blood from flowing normally. This blockage prevents the brain from receiving adequate amounts of oxygen and can result in brain damage or death. Ischaemic stroke is the most common form of stroke, accounting for 80% of all strokes.

LOW-MOLECULAR-WEIGHT HEPARIN

An anticoagulant medication (blood-thinner) used to treat venous thromboembolism (VTE) and prevent the formation of blood clots. Heparin occurs naturally in the blood and helps to prevent the blood from coagulating and forming a clot.

LUPUS ANTICOAGULANT

One of three antibodies (see Antibody) produced in antiphospholipid syndrome (see Antiphospholipid syndrome) which can increase the risk of forming blood clots.

MULTIPARITY

Having more than one child at a time, ie. Twins, triplets.

OESTROGEN

One of the main female sex hormones. Oestrogen carries an increased risk of forming dangerous blood clots.

PAROXYSMAL ATRIAL FIBRILLATION

One of the three forms of atrial fibrillation. Paroxysmal atrial fibrillation is diagnosed when patients experience atrial fibrillation occasionally (see Atrial fibrillation).

PE

See Pulmonary Embolism.

PHARMACOLOGICAL CARDIOVERSION

A medical technique used to treat atrial fibrillation in which a medication or medications are prescribed in order to re-establish the normal rhythm of the heartbeat.

PHOSPHOLIPIDS

A component of cell membranes. Phospholipids are present in every cell in the body. Importantly, they make up the cell membrane which encapsulates the contents of the cell. The antibodies (see Antibody) produced in antiphospholipid syndrome (see Antiphospholipid syndrome) target proteins that bind phospholipids on normal cells.

PNEUMATIC COMPRESSION DEVICE

Also known as intermittent pneumatic compression (IPC) devices. These are used to help prevent blood clots in the deep veins of the legs. These are usually made up of an air pump and inflatable sleeves or boots which increase the pressure on the legs momentarily and then release, increasing blood flow from the surface to the deep veins, preventing blood from pooling and forming clots.

POST-THROMBOTIC SYNDROME (PTS)

A long-term complication of a deep vein thrombosis (DVT) (see Deep vein thrombosis). Also known as post-phlebitic syndrome. This occurs in more than one third of people who have a DVT. PTS occurs when the veins are damaged as a result of a DVT. PTS can cause leg pain and swelling, a feeling of heaviness or tingling, cramps, and ulcers on the legs.

PREECLAMPSIA / ECLAMPSIA

A complication which may occur during pregnancy characterised by high blood pressure and potential organ damage (liver or kidneys). Both preeclampsia and eclampsia are risk factors for developing dangerous blood clots.

PROTEIN C

Protein C is a natural anticoagulant found in the blood. Protein C helps to prevent clotting, so having a Protein C deficiency makes you more likely to form dangerous clots. Protein C deficiency affects 1 in 500 adults worldwide. 

PROTEIN S

Protein S is a natural anticoagulant found in the blood. If you do not have enough Protein S then your blood is more likely to clot. Protein S deficiency affects 1 in 500 adults worldwide. 

PROTHROMBIN

Prothrombin is a protein found naturally in the blood which helps the blood to clot.

PROTHROMBIN 20210

Prothrombin 20210 (also known as Factor II mutation) is a genetic disorder that increases the amount of prothrombin in the blood and thereby increases the likelihood of developing dangerous blood clots. Prothrombin 20210 is the second-most common form of inherited thrombophilia (see Inherited thrombophilia).

PULMONARY EMBOLISM (PE)

A blockage in one of the pulmonary arties of the lungs caused by a blood clot that has travelled to the lung from the deep veins in the legs (a deep vein thrombosis or DVT) or elsewhere in the body.

RIVAROXABAN

A direct oral anticoagulant (DOAC) (see Direct oral anticoagulants) or medication used to prevent the formation of blood clots.

THROMBOEMBOLIC STROKE

Also known as thrombotic stroke. This is when a blood clot (or thrombus) forms inside one of the brain’s arteries and blocks blood flow to the brain. This results in the brain not receiving adequate amounts of oxygen and causing potential brain damage to that area.

THROMBOEMBOLISM

When a blood clot that has formed in a blood vessel dislodges or “breaks away” from the vessel wall and travels through the blood stream. The most common kind of thromboembolism is a pulmonary embolism (PE).

THROMBOLYSIS

The breaking-down of a blood clot (or thrombus). From thrombus and -lysis meaning to break down.

THROMBOLYTIC

A medication is thrombolytic if it causes the break down of blood clots.

THROMBOPHILIA

Thrombophilia is a condition in which your blood is more likely to clot. Thrombophilia can be inherited (such as Factor V Leiden) or acquired (such as in the use of the combined oral contraceptive pill). Thrombophilia is an important risk factor for conditions like venous thromboembolism (VTE) and can increase your chances of forming dangerous blood clots.

THROMBOPHLEBITIS

Thrombophlebitis is a condition in which a blood clot forms in a vein and causes inflammation and pain. Phlebitis means inflammation in a vein. Thrombophlebitis most commonly occurs in your legs but can occur elsewhere in your body as well.

THROMBOSIS

The formation of a blood clot within a blood vessel.

THROMBUS

A blood clot.

UNFRACTIONATED HEPARIN (UFH)

A protein that is naturally found in the blood and is used as a fast-acting blood thinning medication (anticoagulant). UFH is used to prevent blood clots from forming or growing larger.

VALVULAR HEART DISEASE

A condition in which one of the four valves in your heart is damaged and doesn’t work properly. This condition can cause blood flow through your heart to be disrupted and can increase the chance of blood pooling and forming a dangerous blood clot.

VASCULAR THROMBOEMBOLISM (VTE)

When a blood clot that has formed in vein dislodges or “breaks away” from the vessel wall and travels through the blood stream. VTE is a condition that includes both deep vein thrombosis (DVT) – when a blood clot forms in the deep veins of the legs, and pulmonary embolism (PE) – when the blood clot dislodges and travels to the pulmonary arteries of the lungs.

VTE

See Vascular Thromboembolism.

WARFARIN

 A direct oral anticoagulant (DOAC) (see Direct oral anticoagulants) or medication used to prevent the formation of blood clots.