ABCD2 risk score does not predict the presence of cerebral microemboli in patients with hyper-acute symptomatic critical carotid artery stenosis. Issue 2 (17th March 2017)

• Record Type: Journal Article
• Authors: Saedon, Mahmud; Hutchinson, Charles E; Imray, Christopher H E; Singer, Donald R J
• Is Part Of: Stroke and vascular neurology. Volume 2:Issue 2(2017)
• Page Start: 41
• Page End: 46
• Publication Date: 2017-03-17
• Subjects: Platelets -- Stroke -- microemboli -- transcranial doppler; Cerebrovascular disease -- Periodicals; Cardiovascular system -- Diseases -- Periodicals; 616.81005
• DOI: 10.1136/svn-2017-000073
• Languages: English
• ISSNs: 2059-8688

Abstract

Abstract : Introduction: ABCD 2 risk score and cerebral microemboli detected by transcranial Doppler (TCD) have been separately shown to the predict risk of recurrent acute stroke. We studied whether ABCD 2 risk score predicts cerebral microemboli in patients with hyper-acute symptomatic carotid artery stenosis. Participants and methods: We studied 206 patients presenting within 2 weeks of transient ischaemic attack or minor stroke and found to have critical carotid artery stenosis (≥50%). 86 patients (age 70±1 (SEM: years), 58 men, 83 Caucasian) had evidence of microemboli; 72 (84%) of these underwent carotid endarterectomy (CEA). 120 patients (age 72±1 years, 91 men, 113 Caucasian) did not have microemboli detected; 102 (85%) of these underwent CEA. Data were analysed using X 2 and Mann–Whitney U tests and receiver operating characteristic (ROC) curves. Results: 140/206 (68%: 95% CI 61.63 to 74.37) patients with hyper-acute symptomatic critical carotid stenosis had an ABCD 2 risk score ≥4. There was no significant difference in the NICE red flag criterion for early assessment (ABCD 2 risk score ≥4) for patients with cerebral microemboli versus those without microemboli (59/86 vs 81/120 patients: OR 1.05 ABCD 2 risk score ≥4 (95% CI 0.58 to 1.90, p=0.867)). The ABCD 2 risk score was <4 in 27 of 86 (31%: 95% CI 21 to 41) embolising patients and in 39 of 120 (31%: 95% CI 23 to 39) without cerebral microemboli. After adjusting for pre-neurological event antiplatelet treatment (APT), area under the curve (AUC) of ROC for ABCD 2 risk score showed no prediction of cerebral microemboli (no pre-event APT, n=57: AUC 0.45 (95% CI 0.29 to 0.60, p=0.531); pre-event APT, n=147: AUC 0.51 (95% CI 0.42 to 0.60, p=0.804)). Conclusions: The ABCD 2 score did not predict the presence of cerebral microemboli or carotid disease in over one-quarter of patients with symptomatic critical carotid artery stenosis. On the basis of NICE guidelines (refer early if ABCD 2 ≥4), assessment of high stroke risk based on ABCD 2 scoring may lead to inappropriate delay in urgent treatment in many patients.