Because the benefits from thrombolytic therapy in acute myocardial infarction (AMI) are time dependent, multiple strategies have been devised to speed therapy. This study sought to determine whether hospital-based nurse and paramedic advanced life support (ALS) providers could be trained to independently evaluate (sight read) a prehospital 12-lead electrocardiogram (ECG) for the presence of AMI as part of a protocol designed to speed in-hospital administration of thrombolytic agents. Providers were required to determine on the basis of a protocol (1) whether or not AMI was present, and (2) whether or not thrombolytic therapy was indicated. Providers then radioed their impression to the emergency department (ED) and initiated a protocol to prepare identified candidates for thrombolysis. The final decision to initiate thrombolytic therapy was made by the ED physician after patient arrival at the hospital. One hundred fifty-five patients with chest pain were studied. Twenty-one (13.5%) were ultimately proven in-hospital to have AMI. Providers were able to recognize AMI in 17 of 21. Four of 21 did not meet ECG criteria for AMI on the field ECG, but were categorized as having a high index of suspicion for AMI by providers. There were no false-positive diagnoses. Fourteen patients (9%) received thrombolytic therapy. In-hospital times to administration of thrombolytic therapy decreased to an average of 22 +/- 13.8 minutes in the studied group compared with a historical control group average of 51 +/- 50 minutes. It is concluded that hospital-based paramedics and nurses can successfully be taught to evaluate (ie, sight read) a prehospital ECG for the presence of AMI with accuracy.(ABSTRACT TRUNCATED AT 250 WORDS)