Intracranial hemorrhage due to long-term anticoagulant therapy in patients with prosthetic heart valves--four case reports.

Four patients with prosthetic heart valves suffered intracranial hemorrhage (cerebral hemorrhage in one patient, cerebellar hemorrhage in one, and chronic subdural hematoma in two) during long-term oral anticoagulant drug therapy (warfarin). In all patients, warfarin was discontinued and its effect neutralized by vitamin K, then surgery was performed after the thrombotest value exceeded 50%. No uncontrollable bleeding occurred at surgery. Warfarin was discontinued until 3-7 days postoperatively. Intravenous heparin administration was used to prevent embolic complications and the dose was modified based on the activated clotting time measured at the bedside. One patient, who could not receive heparin administration because of massive bleeding, developed myocardial infarction due to coronary artery thromboembolism 2 days after operation and died 4 days later. The other patients received heparin administration and were alive and well at the most recent follow-up examinations. Heparin administration monitored by activated clotting time is a useful method to prevent embolic and bleeding complications in the surgical treatment of intracranial hemorrhage in patients with prosthetic heart valves receiving long-term anticoagulant therapy.