Between 1993 and 1997 in the UK, the proportion of myocardial infarction patients receiving thrombolysis within 90 minutes of calling for help increased, driven by faster emergency department treatment despite longer patient delays in seeking help.
OBJECTIVE: To evaluate trends in provision of thrombolytic treatment between 1993 and 1997. DESIGN: Observational study. SUBJECTS: 3714 patients in 15 UK hospitals who had an admission diagnosis of myocardial infarction. MAIN OUTCOME MEASURES: Changes in prehospital and hospital delay before thrombolytic treatment; use of emergency services. RESULTS: Between 1993 and 1997 the proportion of patients who called for help within 30 minutes of the onset of symptoms fell from 42.6% to 36.0%; difference 6.6% (95% confidence intervals (CI) 3.3% to 10%). The direct use of the emergency service by patients and by doctors sending an ambulance without seeing the patient increased by 18.9%. Patients given thrombolytic treatment within 90 minutes of calling for help increased from 28.2% to 39.1%; difference 10.9% (95% CI 7.2% to 14.7%). Over the same period the proportion of patients treated in emergency departments increased from 4.4% to 17.3%, and the median delay from arrival to treatment in emergency departments fell from 53 to 36 minutes. Median delays for patients treated in cardiac care units after assessment in the emergency department fell from 63 to 54 minutes. CONCLUSION: Between 1993 and 1997 there was an increase in the proportion of patients with definite infarction having thrombolytic treatment within 90 minutes of a call for help. This was mainly the result of greater use of the emergency service and more rapid treatment of a larger proportion of eligible patients in emergency departments. Longer delays by patients have cancelled out some of this improvement.
John Birkhead (1999) studied this question.