Delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage : the role of coagulation and fibrinolysis

Patients with aneurysmal subarachnoid hemorrhage (SAH) are at risk to develop complications, especially within the first two weeks after the hemorrhage. Delayed cerebral ischemia (DCI) is a complication which occurs in about 30% of SAH patients, leading to symptoms such as aphasia, hemiparesis, or impaired level of consciousness. The cause of DCI remains unknown, however many clinicians still are convinced that DCI is caused by vasospasm. Indeed, several studies found a strong association between radiologically confirmed spasm and clinical signs of DCI, but an association is not a causal relation. In this thesis it is shown that microthrombosis, as a result of activation of the coagulation cascade and impairment of fibrinolytic activity, plays a role in the development of DCI.