MYOCARDIAL INFARCTION, FIBRINOLYSIS, ANTIFIBRINOLYTIC DRUGS AND HAEMOSTATICS

MYOCARDIAL INFACTION

Most heart attacks are caused by a blood clot that blocks one of the coronary arteries. The coronary arteries bring blood and oxygen to the heart. If the blood flow is blocked, the heart is starved of oxygen and heart cells die.

The medical term for this is myocardial infarction.

Causes

A substance called plaque can build up in the walls of your coronary arteries. This plaque is made up of cholesterol and other cells.

A heart attack may occur when:

-A tear in the plaque occurs. This triggers blood platelets and other substances to form a blood a clot at the site that blocks blood from flowing to the heart. This is the most common cause of heart attack.

-A slow buildup of plaque may narrow one of the coronary arteries so that it is almost blocked.

The cause of heart attack is not always known.

Heart attack may occur:

-when you are resting or asleep

-after a sudden increase in physical activity

-when you are active outside in cold weather

-after sudden, severe emotional or physical stress, including an illness.

Symptoms

Chest pain is the most common symptom of a heart attack.

You may feel the pain in only one part of your body OR pain may move from your chest to your arms, shoulder, neck, teeth, jaw, belly area, or back.

The pain can be severe or mild. It can feel like:

-a tight band around the chest

-bad indigestion

-something heavy sitting on your chest

-squeezing or heavy pressure.

The pain most often lasts longer than 20 minutes. Rest and a medicine to relax the blood vessels (called nitroglycerin) may not completely relieve the pain of a heart attack. Symptoms may also go away and come back.

Other symptoms of a heart attack can include: anxiety, cough, fainting, light-headedness, dizziness, nause or vomiting, palpitations, shortness of breath ans sweating.

Some people (the elderly, people with diabetes, and women) may have little or no chest pain. Or, they may have unusual symptoms such as shortness of breath, fatigue, and weakness. A "silent heart attack" is a heart attack with no symptoms.

FIBRINOLYTIC DRUGS
Fibrinolytic drugs act as thrombolytics by activating plasminogento form plasmin, which degrades fibrin and so breaks up thrombi.
-Alteplase (Actilyse).
-Reteplase (Rapilysin).
-Streptokinase (Streptase).
-Tenecteplase (Metalyse).
-Urokinase.

ANTIFIBRINOLYTIC DRUGS AND HAEMOSTATICS
-Etamsylate: blood loss in menorrhagia (Dicynene).
-Tranexamic acid: it can be used to prevent bleeding or to treat bleeding associated withexcessive fibrinolysis (Cyklokapron).

Blood products:
-Antithrombin III concentrate: indicated for congenital deficiency of antithrombin III.
-Dried prothrombin complex.
-Drotrecogin alfa (activated).
-Factor VIIa (recombinant).
-Factor VIII fraction, dried.
-Factor VIII inhibitor bypassing fraction.
-Factor IX fraction, dried.
-Factor XIII fraction, dried.
-Fresh frozen plasma.
-Protein C concentrate.

Source:
-http://www.nlm.nih.gov/medlineplus/ency/article/000195.htm
-BNF 57 March 2009