Clot-selective coronary thrombolysis with pro-urokinase

Area of Science:

• Cardiology
• Thrombolytic Therapy
• Biochemistry

Background:

• Myocardial infarction is primarily caused by coronary thrombosis, necessitating effective thrombolytic treatments.
• Tissue plasminogen activator (t-PA) shows limitations in reperfusion rates, speed, and increased risk of hemorrhagic stroke at higher doses.
• A need exists for safer and more effective thrombolytic regimens for acute myocardial infarction.

Purpose of the Study:

• To evaluate the efficacy and fibrin specificity of pro-urokinase in patients with acute myocardial infarction.
• To compare the thrombolytic properties of pro-urokinase with those of t-PA.

Main Methods:

• A multicenter study involving 40 patients with acute myocardial infarction and complete coronary occlusion (TIMI grade 0).
• Pro-urokinase was administered intravenously over 90 minutes, 3.9 +/- 1.1 hours after chest pain onset.
• Measurements included reperfusion rates (TIMI grade 2 or 3), time to reperfusion, and changes in fibrinogen, alpha 2-antiplasmin, plasminogen, fibrinogen degradation products, and D-dimer.

Main Results:

• Reperfusion was achieved in 51% (20 of 39) of patients, with an average time to reperfusion of 64.8 +/- 22.3 minutes.
• Pro-urokinase demonstrated relative fibrin specificity, with only a 10% decrease in fibrinogen levels.
• However, non-specific effects were observed, including decreases in alpha 2-antiplasmin (39%) and plasminogen (64%), and increases in fibrinogen degradation products (63%) and D-dimer (8.7-fold).

Conclusions:

• Pro-urokinase facilitates relatively clot-selective coronary thrombolysis in acute myocardial infarction, comparable to t-PA.
• While fibrin-specific, higher doses of pro-urokinase or t-PA alone may lead to more non-specific systemic effects.
• Further research into optimal dosing and combinations may be warranted to maximize efficacy and minimize side effects.