This study of brain autopsy findings in 229 cases of endocarditis (67 anticoagulated, 162 non-anticoagulated) shows that treatment with anticoagulation does not increase the incidence of cerebral hemorrhage, neither from the conversion of ischaemic necroses into hemorrhagic ones nor from an increase in other circulatory or vascular lesions. The analysis was based on the pathogenesis and detailed descriptions of the lesions, paying particular attention to hemorrhagic infarctions of the cerebral cortex. Using chi-square analysis, there was no significant difference between the frequency of lesions in anticoagulated versus non-anticoagulated patients.