Italian symptomatic intracranial atherosclerosis study (ISIDE) : A multicenter transcranial ultrasound evaluation

Abstract

There are currently no data available on the prevalence of symptomatic intracranial atherosclerosis (ICAS) in Italy. The aim of this prospective, multicenter, hospital-based, transcranial ultrasound study was to establish the prevalence of ICAS among patients hospitalized with acute ischemic stroke. At 11 stroke centers across Italy, patients consecutively admitted for their first ever acute ischemic stroke were assessed prospectively over a 24-month period either with transcranial color-coded Doppler sonography (TCCS) or transcranial Doppler (TCD) according to validated criteria. ICAS was diagnosed when there was an evidence of a cerebral infarction in the territory of a ≥50 % stenosis detected by TCCS/TCD and confirmed by magnetic resonance angiography or computed tomography angiography. A total of 1134 patients were enrolled, 665 of them (58.6 %) men, with a mean age of 71.2 ± 13.3 years. ICAS was recorded in 99 patients (8.7 % of the whole sample, 8.9 % among Caucasians), most commonly located in the anterior circulation (63 of 99, 5.5 %). After adjusting for potential confounders, multivariate analysis identified carotid/vertebral ≥50 % stenosis [odds ratio (OR) 2.59, 95 % (confidence interval) CI 1.77-6.33; P = 0.02] and hypercholesterolemia (OR 1.38, 95 % CI 1.02-1.89; P = 0.02) as being independently associated with ICAS. ICAS is a surprisingly relevant cause of ischemic stroke in Italy, identified in almost 9 % of first-ever stroke patients. It is more prevalent in the anterior circulation and independently associated with hemodynamically significant cervical vessel atherosclerosis and hypercholesterolemia. These findings support the systematic use of transcranial ultrasound to identify ICAS in patients presenting with acute ischemic stroke and in cases with ≥50 % cervical vessel stenoses.

Keywords: ICAS; Stroke; Symptomatic intracranial atherosclerosis; Ultrasound.