European Infarction Study (E.I.S.). A secondary prevention study with slow release oxprenolol after myocardial...

A multicentre, double-blind, randomized study was carried out to compare the effect on survival, cardiac mortality and non-fatal cardiac events of oxprenolol slow release 160 mg b.i.d. compared with placebo in 1741 patients 35 to 69 years of age who had survived acute myocardial infarction. The patients were entered 14-36 days after infarction and were followed for one year. Recruitment was discontinued before the scheduled 4000 patients had been entered. There were 57 deaths (6.6%) in patients randomized with respect to oxprenolol as compared with 45 deaths (5.1%) in patients randomized with respect to placebo. The difference in cumulative mortality rates (30.4%) is not statistically significant. 275 patients from each treatment group discontinued trial medication. The proportion of deaths was noted to be higher in patients who discontinued trial medication (oxprenolol 13.1%; placebo 7.6%) and in patients 65-69 years (oxprenolol 16.7%; placebo 5.6%). In the 1472 patients less than 65 years of age there was a tendency to a lower mortality in 478 'high risk' patients on beta-blockade [oxprenolol 16 patients (6.9%); placebo 25 patients (10.2%)] as compared with a somewhat higher mortality in the corresponding low risk group (oxprenolol 20 patients [4.0%]; placebo 12 patients [2.4%]). In the 1010 patients under 65 years of age who continued on trial medication, 15 patients (3%) in the oxprenolol group and 22 patients (4.3%) in the placebo group died. The overall results in our trial failed to confirm apparently positive effects in other secondary prevention trials. Debate especially concerns patients older than 65 years of age, patients at relatively low risk, and patients who discontinued oxprenolol treatment.