Reducing time to treatment in acute myocardial infarction.

The earliest possible initiation of reperfusion therapy is necessary to prevent extended necrosis, preserve ventricular function, and reduce morbidity and mortality from acute myocardial infarction. Therefore, improving the time to thrombolysis is a critical goal of patient management. Four complementary strategies have been employed in an attempt to shorten the time to thrombolytic therapy: (1) public education to shorten the delay in summoning help, (2) prehospital thrombolysis by trained emergency-response personnel, (3) implementation of emergency department thrombolysis protocols, (4) and the use of rapid diagnostic techniques to confirm acute myocardial infarction. Currently available fibrinolytic agents do not lend themselves to emergency use. Therefore, new thrombolytic agents have been bioengineered with characteristics that make them better suited for use in this setting. Two of these agents, TNK-t-PA and nPA, have extended half-life profiles that permit single-bolus dosing--an important consideration when fibrinolytic therapy is initiated outside the coronary care unit. The most effective system will integrate these complementary strategies to deliver continuous patient care from the time of the call for help, through emergency response, transportation, hospital admission, assessment, and initiation of thrombolytic therapy.