Comparison of Carotid Atherosclerotic Plaque Characteristics between Symptomatic Patients with Transient Ischemic Attack and Stroke using Multi-Contrast Magnetic Resonance Imaging

Purpose: This study aimed to compare the characteristics of carotid plaques between patients with transient ischemic attack (TIA) and ischemic stroke using magnetic resonance (MR) imaging. Methods： Symptomatic patients with carotid atherosclerotic plaque who had a recent ischemic stroke or TIA were recruited and underwent carotid MR imaging. The characteristics of plaque morphology and compositions including intraplaque hemorrhage (IPH), lipid-rich necrotic-core (LRNC) and calcification were compared between TIA and stroke patients. Logistic regression was performed to relate the plaque characteristics to the types of ischemic events. Results: A total of 270 patients with TIA or ischemic stroke were recruited. Stroke patients had significantly higher prevalence of diabetes (42.2% vs. 28.2%, p= 0.021), greater mean wall area (35.1 ± 10.1 mm 2 vs. 32.0 ± 7.7mm 2 , p = 0.004), mean wall thickness (1.3 ± 0.2 mm vs. 1.2 ± 0.2 mm, p= 0.001), maximum normalized wall index (NWI)(63.9% ± 6.0% vs. 62.2% ± 5.9%, p= 0.023)and %volume of LRNC(9.7%± 8.2% vs. 7.4% ±7.9%, p= 0.025)in carotid arteries compared to those with TIA. After adjusted for clinical factors, above characteristics of carotid arteries were significantly associated with the type of ischemic events. After further adjusting for maximum NWI, the association of %volume of LRNC and stroke subtype remained statistically significant (OR, 1.41; CI, 1.01-1.96; p= 0.041). Conclusions: Ischemic stroke patients had larger plaque burden and greater proportion of LRNC in symptomatic carotid plaques compared to patients with TIA. This study suggests that ischemic stroke patients had more vulnerable plaques compared to those with TIA.