Early thrombolytic therapy in suspected acute myocardial infarction--role of the electrocardiogram: results from the TEAHAT Study.
In a placebo-controlled trial in which rt-PA was administered to patients within 2 h and 45 min after the onset of symptoms indicative of acute myocardial infarction (AMI), 352 patients were randomized. Standard 12-lead electrocardiograms (ECGs) were recorded at inclusion and repeatedly during admission and at follow-up after 1 month and 1 year. In patients who presented with ST-segment elevation, the infarction rate was high (88%), whereas in patients without ST-elevation the infarction rate was low (21%), and infarct size, as assessed by serum enzyme activities, was small in this group. There were only minor differences between rt-PA- and placebo-treated patients with regard to ST-segment changes and Q-wave development, whereas the R-wave amplitude was higher after 1 month in patients who were given rt-PA. The infarction rate was not altered by rt-PA, but there was a shift towards a reduction in Q-wave infarction in patients who were treated with rt-PA. When a score system, as suggested by Palmeri et al., intended to reflect the ultimate infarct size, was applied, a significantly lower score was found in infarction patients who were treated with rt-PA as compared to placebo (3.95 +/- 0.35 vs. 2.95 +/- 0.29, P = 0.03), indicating limitation of infarct size. In summary, early treatment with rt-PA resulted in less frequent Q-wave infarction and a reduction in the electrocardiographically estimated infarct size.
Risenfors
M
M
Department of Medicine I, Sahlgrenska Hospital, Göteborg, Sweden.
Zukauskiene
I
I
Albertsson
P
P
Hartford
M
M
Lomsky
M
M
Herlitz
J
J
D000368:Aged; D000553:Ambulatory Care; D004562:Electrocardiography; D005500:Follow-Up Studies; D006801:Humans; D009203:Myocardial Infarction / Q000175:diagnosis / Q000188:drug therapy*; D015912:Thrombolytic Therapy; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*
D010959:Tissue Plasminogen Activator