[How many patients with acute myocardial infarction can be treated by thrombolysis?].

Thrombolytic treatment of acute myocardial infarction (MI) is limited by the time elapsed since onset, accuracy of the diagnosis and the presence of contra-indications. These factors were prospectively investigated in 173 consecutive patients with proven acute MI, admitted to a city hospital between July and December 1986. Fifty-eight patients (35%) were admitted within three hours of onset of symptoms. Delay in calling a doctor or ambulance was significant: 50% of patients waited for more than two hours after onset of symptoms, 40% more than three hours. Duration of transport to hospital averaged 30 min. Infarct-typical angina of at least 30 min had been present in 143 patients (83%). Atypical symptoms and silent MI was more frequent in the older patients. Diagnostic ST segment elevation of 2 to 3 mm on admission was present in 59 (34%) patients. After consideration of contraindications, present in 120 patients with altogether 165 potential factors, thrombolytic treatment was possible in only seven (4%) of those with the greater ST elevations within three hours after onset of symptoms and 13 (7.5%) within six hours. The most frequent contraindications were age (over 75 years), hypotension, re-infarction at the same site, intramuscular injections (unspecified drugs) within the preceding seven days, or resuscitation with cardiac massage before admission.