Giving patients access at home to tape recordings of their hospital discharge information was thought to improve the patient information. There could be an effect on their knowledge of their own disease and possibly also on clinical events. 50 patients with first time myocardial infarction were included; 26 received tape recordings and tape players. 24 patients were included as controls. The equipment was returned after one week, and the patients were followed up with a questionnaire after one, eight and 52 weeks. No difference in medical knowledge was observed. However, fewer patients in the tape group had long term sick leaves, and readmissions or need for emergency visits were less common. Baseline characteristics were almost the same in the two groups. Since acquired knowledge about their own disease did not appear to differ, an effect of the tape information upon the patient's family is considered.