Pre-hospital treatment of patients with suspected acute myocardial using a beta-blocking agent: a double-blind...

The efficacy of intravenous beta-blocker treatment in hospital patients with acute myocardial infarction (AMI) in reducing short-term mortality and morbidity has been demonstrated; the efficacy seems to be higher the earlier the treatment is administered. We assessed the feasibility of pre-hospital treatment of patients in a randomised, double-blind, controlled pilot study. Eligible patients (symptoms suggestive of AMI for less than 2 h) were randomised by mobile emergency unit staff to receive either pre-hospital beta-blocker treatment (intravenous injection of atenolol) immediately, followed by placebo in hospital, or the opposite. All patients received a 7-day course of oral atenolol at the discretion of the hospital physician. A total of 77 patients were included (41 in the pre-hospital beta-blocker group and 36 in the pre-hospital placebo group). Sixteen patients in each group received active treatment, but only 9 and 11 patients, respectively, received full treatment. The reasons for the non-administration of the second injection included the occurrence of adverse events after the first injection, and a certain reserve on the part of the hospital physicians to administer beta-blocker treatment in patients with suspected myocardial infarction. Three patients in each group died; the minor adverse event rate was similar in the two groups. The findings of the study suggest that this approach would be feasible in terms of safety. However, a large number of patients did not receive any hospital treatment for a number of reasons which must be considered if a large-scale trial is to be undertaken.