Hyperacute Vasospasm After Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Cerebral vasospasm after aneurysmal subarachnoid hemorrhage typically occurs 3-14 days after aneurysm rupture. We describe a series of patients who developed vasospasm within minutes of aneurysm rupture. This phenomenon, which we term, "hyperacute vasospasm," has been reported in animal models of SAH, but hitherto has been poorly described in humans.

METHODS: Eleven patients were identified from an institutional registry who had aneurysmal rupture during catheter cerebral angiography between 1997 and 2009. We quantified the degree of vasoconstriction using vascular diameter index (VDI). The change in VDI (delta VDI or DVDI) was calculated by determining the difference in VDI before and after the procedure. We also examined the relationship between hyperacute vasospasm and delayed cerebral ischemia.

RESULTS: Ten of eleven (91%) patients with intraoperative aneurysm rupture had cerebral vasoconstriction within minutes of intra-procedural aneurysmal rupture. Six of eleven patients (55%) with hyperacute vasospasm developed delayed cerebral infarction.

CONCLUSIONS: Hyperacute vasospasm is likely common in patients with intraoperative aneurysm rupture and may be an unrecognized element of the natural history of aneurysmal subarachnoid hemorrhage. In this limited series, there was an association between hyperacute vasospasm and delayed cerebral infarction.