The 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, known as statins, have recently been demonstrated to improve endothelial function. Additionally, numerous studies have shown statins as having antiinflammatory and cell-signaling effects together with a selective up-regulation of the eNOS activity. These findings are of potential benefit for the prevention of cerebral vasospasm after a aneurysmal subarachnoid hemorrhage. Indeed, one of the possible mechanisms for this vasospasm is the eNOS depletion or even increase of eNOS expression after the hemorrhage. The purpose of this study is to observe the immediate effect of statins after aneurysmal subarachnoid hemorrhage (aSAH) in cerebral vasospasm and outcome at one year.