Hemorrhagic infarction after vasospasm due to ruptured cerebral aneurysm.

Hemorrhagic infarction after vasospasm is a rare condition in patients with aneurysmal subarachnoid hemorrhage (SAH). Induced hypertensive therapy is used for patients with vasospasm, but this treatment has a risk of inducing hemorrhagic infarction. A total of 221 patients whose first computed tomographic (CT) scans were examined within 2 weeks after SAH were investigated for this study. There was symptomatic vasospasm in 99 (45%), cerebral infarction in 37 (17%), and hemorrhagic infarction in 13 (6%). Hemorrhagic infarction usually occurred 20 to 30 days after aneurysmal rupture; this period corresponds with the remission stage of the vasospasm. On CT scans, the hemorrhagic infarction was revealed as a leaky hemorrhage in a low density area in 11 cases, and a massive hemorrhage with mass effect was seen in 2 cases. These findings suggest that hemorrhagic infarction after vasospasm may sometimes be fatal. Cerebral blood flow autoregulation in patients with vasospasm was normal or of a hypertensive type during the remission stage of vasospasm, when hemorrhagic infarction usually appeared. This finding shows that induced hypertension therapy is ineffective during this stage; it should be stopped by this stage because it is ineffective and also may aggravate hemorrhagic infarction.