Time to thrombolytic treatment: factors affecting delay and their influence on outcome.

One of the major limitations to realizing the full potential of the lifesaving effects of thrombolytic therapy has been the failure to initiate treatment in the first 1 to 1.5 h after symptom onset. The barriers to early treatment include the following: 1) Most patients fail to react rapidly and appropriately to symptoms. 2) Few emergency medical/paramedic systems have established effective triage systems for patients with chest pain or have implemented prehospital electrocardiography to better manage patients with possible acute myocardial infarction. 3) Time to treatment after hospital arrival currently averages 1 to 1.5 h-two to three times longer than what should be necessary to initiate therapy in the patient with typical electrocardiographic and clinical findings and co-morbid risk factors. Trials evaluating the effects of prehospital-initiated therapy have all shown trends toward a reduction in mortality (18%) associated with early treatment; however, none has been large enough in and of itself to be conclusive. The goal in the coming years will be to decrease each of these components of delay by developing effective education programs for the lay public, speeding and improving prehospital care by the routine use of electrocardiography and reducing hospital treatment times to < or = 30 min in the "uncomplicated" patient.