A large number of studies have shown the prognosis after acute myocardial infarction (AMI) to be favorably affected by treatment with beta blockers. Whether such treatment also will have a favorable effect on the prognosis in patients in whom AMI was not confirmed has not been shown. A study was undertaken at Sahlgren's Hospital, Göteborg, to determine risk indicators for death and prognosis among 1,443 patients in whom AMI was not confirmed and who survived hospitalization in relation to whether or not beta blockers were prescribed at discharge. One-year mortality was determined and p values were corrected for differences at baseline. Of the 1,443 patients who participated in the analyses, 44% were prescribed beta blockers. They differed from the remaining patients by younger age, predominance of men, a more frequent history of AMI, angina pectoris, and hypertension, and a less frequent history of congestive heart failure. Patients in whom beta blockers were prescribed had a 1-year mortality of 6% compared with 16% in those not on beta blockers (p < 0.001). The difference was similar in various subgroups according to clinical history.