Intraplaque hemorrhage in symptomatic and asymptomatic progressive internal carotid artery stenosis - a pilot study

Aim: Intraplaque hemorrhage (IPH) belongs to potential mechanisms of plaque instability subsequently leading to ischemic stroke. Study aims to compare the IPH occurrence in patients with symptomatic (SS), asymptomatic stable (AS) and asymptomatic progressive (AP) internal carotid artery (ICA) stenosis >= 50%. Materials and methods: Serial duplex ultrasound (DUS) in a 6-month period and MRI using axial 3DT1_MPRAGE sequence were used for IPH detection in patients with ICA stenosis. Stenoses in patients with ipsilateral ischemic stroke / transient ischemic attack within the previous 4 weeks or acute ischemic lesion on diffusion-weighted MRI sequencies were evaluated as symptomatic. Stenoses with progression of > 10% since last DUS examination were evaluated as progressive. Echolucent part of atherosclerotic plaque > 8 mm(2) on DUS and hyperintensity on 3DT1_MPRAGE-MRI were evaluated as PH. Differences in IPH occurrence between SS, AS and AP ICA stenoses were statistically evaluated. Results: A total of 52 patients (33 males, mean age 69.2 +/- 9.0 years) with 59 ICA stenoses were enrolled in the prospective study during 15 months; 13 ICA stenoses were evaluated as SS, 27 as AS and 19 as AR. IPH was detected using DUS/MRI in 6 (46%) / 4 (30%) of SS, 12 (4496) / 8 (30%) of AS, and 11 (58%) / 11 (58%) of AP ICA stenoses (P > 0.05 in all cases). IPH was detected using combination of both methods in 3 (23%) of SS, 4 (15%) of AS, and 7 (36%) of AP ICA stenoses (P > 0.05 in all cases). Conclusion: IPH was more frequently detected in asymptomatic progressive than asymptomatic stable ICA stenoses. No significant differences were found between occurrence of IPH in symptomatic than in asymptomatic progressive ICA stenoses. A total of 200 patients will be enrolled in the ongoing study.