A prospective, randomized study was carried out to investigate whether repeated hospital discharge information on audiotape at home could improve knowledge and rehabilitation in patients with first-time myocardial infarction. The study comprised 50 patients (12 females and 38 males) of up to 75 years of age. At discharge, 26 patients were given tape recordings to use at home for one week, while 24 patients represented controls. High scores in patients' knowledge about their own disease were noted, as well as differences in long-term sick leave between the two groups and readmissions or need for emergency visits. No difference in knowledge was observed, but fewer patients in the tape group had long-term sick leave, readmissions or need for emergency visits. We found that baseline characteristics were similar in the two groups. Since acquired knowledge did not appear to differ between the groups, an effect of the taped information on the patients' family network is considered.