What mechanism of action does a fibrinolytic drug have in treating myocardial infarction?

Fibrinolytic drugs are designed to dissolve blood clots, particularly those that obstruct blood flow to the heart during a myocardial infarction. Their primary mechanism of action involves catalyzing the formation of plasmin, an enzyme that breaks down fibrin in blood clots. By converting plasminogen to plasmin, these medications promote the breakdown of the fibrin mesh that stabilizes thrombi, leading to the dissolution of the clot and restoration of blood flow to the affected area of the heart.

This process is crucial in the acute management of myocardial infarction, as timely re-establishment of perfusion can save heart muscle from damage, reduce morbidity, and improve survival rates. The other mechanisms mentioned, such as inhibiting thrombin or blocking platelet activation, relate to different classes of anticoagulant or antiplatelet therapies and do not directly promote the breakdown of existing clots like fibrinolytics do.