Vasospasm on transcranial Doppler is predictive of delayed cerebral ischemia in aneurysmal subarachnoid hemorrhage: a systematic review and meta-analysis

Abstract

C erebral vasospasm is a major cause of poor outcomes in aneurysmal subarachnoid hemorrhage (aSAH), resulting in cerebral ischemia, infarction, disability, and death. 20,25 Cerebral vasospasm is noted on angiography in as many as 70% of patients following aSAH and is predicted by high mean flow velocities (MFVs) on transcranial Doppler (TCD) ultrasonography. 19,24,26,35 Vasospasm is strongly associated with delayed cerebral ischemia (DCI) 12 and cerebral infarction, 11,39,49 although poor outcomes can still occur in its absence. Of the current techniques available for diagnosing cerebral vasospasm, catheter angiography and CT angiography are invasive, and require contrast-dye injection and radiation exposure, and therefore do not allow dynamic monitoring of vasospasm. 31The radiation exposure and invasive nature of angiography implies that it is not useful for identifying subclinical vasospasm prior to the onset of the condition, and that its use is frequently restricted to confirm prevalent vasospasm abbreviatioNs aSAH = aneurysmal subarachnoid hemorrhage; CI = confidence interval; DCI = delayed cerebral ischemia; df = degrees of freedom; MFV = mean flow velocity; MWE = mean weighted estimate; NPV = negative predictive value; PPV = positive predictive value; TCD = transcranial Doppler. obJective The impact of transcranial Doppler (TCD) ultrasonography evidence of vasospasm on patient-centered clinical outcomes following aneurysmal subarachnoid hemorrhage (aSAH) is unknown. Vasospasm is known to lead to delayed cerebral ischemia (DCI) and poor outcomes. This systematic review and meta-analysis evaluates the predictive value of vasospasm on DCI, as diagnosed on TCD. methods MEDLINE, Scopus, the Cochrane trial register, and clinicaltrials.gov were searched through September 2014 using key words and the terms "subarachnoid hemorrhage," "aneurysm," "aneurysmal," "cerebral vasospasm," "vasospasm," "transcranial Doppler," and "TCD." Sensitivities, specificities, and positive and negative predictive values were pooled by a DerSimonian and Laird random-effects model. results Seventeen studies (n = 2870 patients) met inclusion criteria. The amount of variance attributable to heterogeneity was significant (I 2 > 50%) for all syntheses. No studies reported the impact of TCD evidence of vasospasm on functional outcome or mortality. TCD evidence of vasospasm was found to be highly predictive of DCI. Pooled estimates for TCD diagnosis of vasospasm (for DCI) were sensitivity 90% (95% confidence interval [CI] 77%-96%), specificity 71% (95% CI 51%-84%), positive predictive value 57% (95% CI 38%-71%), and negative predictive value 92% (95% CI 83%-96%). coNclusioNs TCD evidence of vasospasm is predictive of DCI with high accuracy. Although high sensitivity and negative predictive value make TCD an ideal monitoring device, it is not a mandated standard of care in aSAH due to the paucity of evidence on clinically relevant outcomes, despite recommendation by national guidelines. High-quality randomized trials evaluating the impact ...

Increased middle cerebral artery mean blood flow velocity index after stroke thrombectomy indicates increased risk for intracranial hemorrhage

“…It is further possible that hemodynamic changes in the MCA were induced by local endothelial reaction/vasospasm due to the local stimulus by the interventional catheter, as reported in earlier studies 25 26. Most often vasospasm is defined as mean MCA MBF velocity >120 cm/s and such values were observed in only two of our patients 27. A major contribution of vasospasm to our results seems therefore quite unlikely.…”

Polymeric perfluorocarbon nanoemulsions are ultrasound-activated wireless drug infusion catheters

“…Additionally, given that drug uncaging in this technique occurs intravascularly, we note that the broadest pharmacodistribution would occur with uncaging directed to an artery that subtends a large region of the body, especially for a drug that mainly acts on the vessel itself, instead of in a target organ. Notably vasodilating agents, such as nicardipine and verapamil, are used clinically to relieve arterial spasm as seen with cerebral vasospasm and other conditions, 22 by relaxing the smooth muscle of the vessel wall. For example, nicardipine has been shown to relax the wall of the aorta and increase its distensibility in humans.…”

Bedside Ultrasound After Decompressive Craniectomy: A New Standard?

“…While digital subtraction angiography (DSA) represents the gold standard in detection of vasospasm-including eventual vasospasmolysis-DSA it is not feasible for daily routine diagnostics. In a recent study, TCD showed a high sensitivity compared with Perfusion-CT why TCD is a useful tool in daily follow-up [14,15].…”