Biomarkers of vasospasm development and outcome in aneurysmal subarachnoid hemorrhage.

Aneurysmal subarachnoid hemorrhage (SAH) is a neurologic emergency caused by a brain aneurysm burst, resulting in a bleeding into the subarachnoid space. Its incidence is estimated between 4 and 28/10,000 inhabitants and it is the main cause of sudden death from stroke. The prognosis of patients with SAH is directly related to neurological status on admission, to the magnitude of the initial bleeding, as well as to the development of cerebral vasospasm (CVS). Numerous researchers have studied the role of different biomarkers in CVS development. These biomarkers form part of the metabolic cascade that is triggered as a result of the SAH. Hence, among these metabolites we found biomarkers of oxidative stress, inflammation biomarkers, indicators of brain damage, and markers of vascular pathology. However, to the author knowledge, none of these biomarkers has been demonstrated as a useful tool for predicting neither CVS development nor outcome after SAH. In order to reach success on future researches, firstly it should be stated which pathophysiological process is mainly responsible for CVS development. Once this process has been determined, the temporal course of this pathophysiologic cascade should be characterized, and then, perform further studies on biomarkers already analyzed, as well as on new biomarkers not yet studied in the SAH pathology, focusing attention on the temporal course of the diverse metabolites and the sampling time for its quantification.