Immediate hemodynamic effects of thrombolytic therapy on the ischemic myocardium

Thrombolytic agents are used to restore coronary artery perfusion and limit the size of a myocardial infarction. The systemic effects of these drugs, streptokinase (SK), urokinase (UK), and recombinant tissue plasminogen activator (rtPA), have been studied extensively. Although their effects on rheology and late myocardial performance have been well-documented to date, there have not been any studies evaluating the acute hemodynamic consequences of thrombolytics immediately after administration. In this report we use an isolated Langendorf rodent heart preparation to evaluate the acute hemodynamic effects of thrombolytic therapy on both the normal and the ischemic myocardium. We quantified performance by documenting cardiac output, coronary blood flow, and blood pressure. Although each thrombolytic agent significantly transiently impairs cardiac performance, differences in effect between the agents were statistically insignificant. This was also the case with both the normal as well as the ischemic myocardium. The results of this study would not support favoring the use of one of these agents over the other with regards to primary myocardial performance.