Which of the following plasminogen activator (fibrinolytic) can be given as bolus dose in patients with acute myocardial infarction :
**Core Concept**
The management of acute myocardial infarction (AMI) involves restoring blood flow to the affected area, and fibrinolysis is a key component of this process. Plasminogen activators are administered to convert plasminogen into plasmin, which then degrades fibrin clots.
**Why the Correct Answer is Right**
Alteplase is a recombinant tissue plasminogen activator (tPA) that can be administered as a bolus dose in patients with AMI. It works by binding to fibrin in the clot, activating the plasminogen-plasmin system, and thereby dissolving the clot. Alteplase is effective in restoring blood flow to the affected myocardium, reducing infarct size, and improving clinical outcomes. Its bolus administration allows for rapid initiation of fibrinolysis.
**Why Each Wrong Option is Incorrect**
**Option A:** Reteplase is another tPA, but it is administered as a double-bolus regimen, not a single bolus dose. This makes it a less suitable choice for this question.
**Option B:** Streptokinase is a non-specific plasminogen activator that can activate plasminogen, but it is not typically administered as a bolus dose in AMI. It requires a longer infusion period to achieve therapeutic effects.
**Option C:** Urokinase is a plasminogen activator, but it is not commonly used for fibrinolysis in AMI due to its relatively low specificity and higher risk of bleeding complications.
**Clinical Pearl / High-Yield Fact**
In patients with AMI, timely administration of fibrinolytic therapy within 3-4.5 hours of symptom onset can significantly improve survival and reduce morbidity. Alteplase and other tPAs are preferred due to their higher efficacy and better safety profiles compared to streptokinase.
**Correct Answer:** A. Alteplase.