Hematologic disorders and ischemic stroke.

Hematologic disorders that induce a thrombotic tendency contribute to overall ischemic stroke risk and may directly cause cerebral ischemia in patients without other risk factors. These disorders include platelet dysfunction, prothrombotic coagulopathies, defective fibrinolysis, abnormal red blood cell-vessel wall interactions, and antiphospholipid antibody syndromes. Multiple mechanisms promoting ischemia may underlie specific hematologic abnormalities. Improved markers for activation of platelets, coagulation and fibrinolysis are now being used to correlate prothrombotic mechanisms with ischemic pathology and, thus, to make therapeutic approaches more precise. Nevertheless, finding the ideal balance between preventing cerebral ischemia and incurring hemorrhagic toxicity remains difficult.