Objectives: Our aim was to determine the time saved by administration of thrombolytic therapy at home rather than in the hospital and to assess whether earlier thrombolysis resulted in decreased mortality from acute myocardial infarction.
Background: There is much theoretic, experimental and trial evidence to indicate that in acute myocardial infarction the earlier that thrombolytic therapy is given, the greater its efficacy. However, the clinical importance of this time effect is uncertain.
Methods: In a randomized double-blind parallel-group clinical trial, 311 patients with suspected acute myocardial infarction seen by their general practitioners within 4 h of symptom onset were given intravenous anistreplase (30 U) either at home or later, after arrival in the hospital.
Results: Anistreplase was given at home or in the hospital at median times of 101 and 240 min, respectively, after symptom onset. The median time saved by domiciliary thrombolysis was 130 min. By the end of 1 year after trial entry, 17 (10.4%) of 163 patients given anistreplase at home died compared with 32 (21.6%) of 148 in those allotted anistreplase in the hospital (relative reduction 52%, 95% confidence interval 14% to 89%, p = 0.007).
Conclusions: In this trial the time saved by domiciliary thrombolysis by primary care physicians was > 2 h. It is likely that a similar time saving would be achieved if prehospital thrombolysis were to become established practice. Prehospital thrombolysis resulted in a halving of the mortality rate from acute myocardial infarction.