Conversion of ischemic to hemorrhagic infarction by anticoagulant administration. Report of two cases with evidence from serial computed tomographic brain scans.

Anticoagulant therapy is appropriate for embolic cerebral infarction due to valvular heart disease or cardiac dysrhythmia, as well as for stroke-in-evolution. Various incidences of hemorrhagic complications have been cited in patients given anticoagulants after stroke or transient cerebral ischemia. Conversion of ischemic to hemorrhagic infarction has been shown to occur experimentally. We describe two patients in whom this conversion occurred in the absence of hypertension or excessive anticoagulation and was substantiated by serial computed tomographic brain scans. This finding suggests that conversion of ischemic to hemorrhagic infarction may occur even with appropriate and carefully administered anticoagulation therapy.