Thrombolysis, also called fibrinolytic therapy, is the breakdown (lysis) of blood clots formed in blood vessels, using medication. It is used in ST elevation myocardial infarction, stroke, and in cases of severe venous thromboembolism (massive pulmonary embolism or extensive deep vein thrombosis). The main complication is bleeding (which can be dangerous), and in some situations thrombolysis may therefore be unsuitable. Thrombolysis can also play an important part in reperfusion therapy that deals specifically with blocked arteries. Source: Wikipedia (en)