Arias EJ, Vajapey S, Reynolds MR, Chicoine MR, Rich KM, Dacey RG Jr., et al. Utility of Screening for Cerebral Vasospasm Using Digital Subtraction Angiography. Stroke. 2015

Cerebral vasospasm (CVS) is a common complication of aneurysmal subarachnoid hemorrhage (aSAH), and is strongly associated with delayed cerebral ischemia (DCI). The gold standard for the diagnosis of CVS is digital subtraction angiography (DSA), but the utility for routine screening with DSA during the early course of aSAH is unclear. Here, the authors evaluate the utility of screening by assessing the frequency of significant CVS in asymptomatic vs mildly symptomatic or unassessable aSAH patients to elucidate whether CVS, even in the asymptomatic patient, might be a clinically useful predictor for subsequent DCI.

In this study, 116 patients underwent screening DSA, of which 79 were asymptomatic from DCI prior to undergoing screening (Group I), 25 were symptomatic and had at least one episode of symptoms concerning for DCI (Group II), and 12 had too poor of an exam to reliably detect symptoms of DCI (Group III). These groups were heterogeneous in that patients in groups II and III were more likely to have a higher Hunt and Hess, as well as modified Fischer scores, indicative of more severe aSAH, at least radiologically. Of the 79 patients in group I, 14 had CVS on screening DSA, but none went on to develop DCI during the hospital course. 10 of these patients did receive treatment for CVS, including intraarterial verapamil in 2 patients, vasopressors for headache in 1 patient, and high rates of IV fluids to maintain euvolemia in 7 patients. Of the 25 patients in group II, 14 patients went on to develop definitive DCI, 12 of which had CVS on the screening DSA and 2 of which did not. Of the 12 patients in group III, 6 patients went on to develop DCI, 4 of whom had CVS on screening DSA and 2 of whom did not (represented in table below). The sensitivity of and specificity of CVS on screening DSA for subsequent DCI was 80% and 71% respectively for groups I and II in total, with an OR of 9.6 for the development of definitive DCI in patients with CVS on screening DSA.

The DSA confirms CVS and subsequent DCI in a high-risk subgroup of the aSAH population. This study provides evidence that screening DSA is not beneficial in patients who are asymptomatic; although 14 patients did have CVS on screening DSA, none of these patients went on to develop DCI. These patients did undergo some therapeutic maneuvers but none were aggressive, calling into question whether these patients would merely have remained asymptomatic for the remainder of their stay regardless of treatment. Screening DSAs, however, are beneficial in patients who do not have reliable examinations (Group III). There was also benefit to a screening DSA in patients who were symptomatic (Group II), although given that they were symptomatic, the DSA might not be considered “screening.”