Background: A certain correlation between unfavorable clinical outcome, incidence of vasospasm, and impaired pressure autoregulation in patients following aneurysmal subarachnoid hemorrhage (aSAH) has been suggested. However, determination of vasospasm is inaccurate and the measurement technique of cerebral vasoreactivity seems not to have been sufficiently validated. Therefore, a correlation of clinical outcome and the extent of angiographic VS was performed using an established autoregulation test.
Material and methods: Proximal and global angiographic vasospasm (pVS, gVS) were determined in bilateral M1 segments. Dynamic tests of pressure autoregulation were performed 1 day before and after, and on the day of angiography using Aaslid's thigh leg cuff test. Patient outcome was assessed using the Extended Glasgow Outcome Scale (GOSE).
Key results: Complete datasets were available for 22 patients. Mean autoregulatory indices (ARI) around the day of angiography were 3.9 ± 2.3. Proximal mean reduction of vessel diameter was -23.3% ± 9.1%. Global vasospasm was not present in 10 hemispheres, mild in 15, moderate in 15, and severe in 4. Hemispheric ARI values and angiographic data showed a significant correlation (pVS -0.382, p = 0.015; gVS -0.477, p = 0.002). The degree of angiographic vasospasm and low ARI values correlated significantly with an unfavorable outcome (0.677, p = 0.001).
Conclusion: Incidence of angiographic vasospasm and impaired clinical outcome seems to be related to impaired pressure autoregulation following aSAH.