Irregular surface of carotid atherosclerotic plaque is associated with ischemic stroke: a magnetic resonance imaging study

Objective To determine the association between the irregularity of carotid plaque surface using multidimensional magnetic resonance imaging(MRI) of ipsilateral acute cerebral infarction(ACI) cases. Methods Patients with recent cerebrovascular symptoms(stroke or transient ischemic attack < 2 weeks) and atherosclerotic plaque in at least one carotid artery were diagnosed by B-mode ultrasound imaging(intima-media thickness ≥ 1.5 mm) and recruited for the present study. Irregular surface was defined when plaque surface was uneven with high and low fluctuation or plaque with surface ulceration. The irregularity of carotid plaque surface was determined on axial or oblique images alone(single-dimension) and on both axial images and oblique images(multidimensions), separately. Univariate and multivariate logistic regression analyses were performed to calculate the odds ratio(OR) and the corresponding 95% CI of the irregular plaque surface in discriminating the presence of ipsilateral ACI. Results A total of 217 included subjects(mean age: 60.7 ± 10.2 years, 149 men) were recruited and 89(41.0%), 88(40.6%) and 118(54.4%) of them exhibited irregular plaque surface on axial, oblique and multidimensional MR images, respectively. The OR of irregularity of the plaque surface was determined by multidimensional MRI to be 5.88(95% CI: 3.16–10.96, P < 0.001) in discriminating the presence of ipsilateral ACI. Following adjustment for clinical confounding factors, this association remained statistically significant(OR = 5.65, 95% CI: 2.53–12.60, P < 0.001). The analysis included further adjustment for the presence of lipid-rich necrotic core, intraplaque hemorrhage and stenosis and the results included that this association also remained statistically significant(OR = 6.08, 95% CI: 2.52–14.68, P < 0.001). Conclusions The irregular plaque surface was determined by multidimensional MRI as an independent indicator for ipsilateral acute cerebral infarction.

Association between antiplatelet medication and cerebral microbleeds in stroke-free population

BACKGROUND Cerebral microbleeds(CMBs)may increase the risk of future intracerebral hemorrhage and ischemic stroke.However,It is unclear whether antiplatelet medication is associated with CMBs.This study aimed to investigate the association between antiplatelet medication and CMBs in a community-based stroke-free population.METHODS In this cross-sectional study,stroke-free participants aged 18-85 years were recruited from a community in Beijing,China.Demographic,clinical,and antiplatelet medication data were collected through a questionnaire,and all participants underwent blood tests and brain magnetic resonance imaging at 3.0T.The presence,count,and location of CMBs were evaluated using susceptibility-weighted imaging.The association between antiplatelet medication and the presence of CMBs was analyzed using multivariable logistic regression.The associations between antiplatelet medication and CMBs by location(lobar,deep brain or infratentorial,and mixed regions)were also analyzed using multinomial logistic regression.A linear regression analysis was conducted to determine the association between antiplatelet medication and the log-transformed number of CMBs.RESULTS Of the 544 participants(mean age:58.65±13.66 years,217 males),119 participants(21.88%)had CMBs,and 64 participants(11.76%)used antiplatelet medication.Antiplatelet medication was found to be associated with CMBs at any location[odds ratio(OR)=2.39,95%CI:1.24-4.58]and lobar region(OR=2.83,95%CI:1.36-5.86),but not with the number of CMBs(β=0.14,95%CI:-0.21-0.48).Among antiplatelet medications,aspirin use was found to be associated with any CMB(OR=3.17,95%CI:1.49-6.72)and lobar CMBs(OR=3.61,95%CI:1.57-8.26).CONCLUSIONS Antiplatelet medication was associated with CMBs in stroke-free participants,particularly lobar CMBs.Among antiplatelet medications,aspirin use was associated with any CMB and lobar CMBs.Our findings suggest that it might be essential to optimize the management of antiplatelet medication in the stroke-free population with a higher burden of vascular risk factors to reduce the potential risk of CMBs.

Association of atherosclerotic plaque features with collateral circulation status in elderly patients with chronic carotid stenosis

Objective To determine the association of carotid plaque features with collateral circulation status in elderly patients with moderate to severe carotid stenosis.Methods Elderly patients(>60 years)with moderate to severe carotid stenosis were recruited and categorized into good and poor collateral circulation groups,and underwent magnetic resonance imaging and computed tomography imaging.The carotid plaque features including lipid-rich necrotic core,intraplaque hemorrhage,calcification,and fibrous cap rupture(FCR)were evaluated,and maximum wall thickness,normalized wall index(NWI),and luminal stenosis were measured.The association between these variables and collateral circulation status was analyzed.Results Of the 97 patients(78 males,mean age:69.0±6.1 years),19(19.6%)had poor collaterals.The poor collateral group had a significantly higher NWI(93.7%±5.0%vs.89.0%±7.9%,P=0.011),a greater extent of stenosis(80.0%±11.4%vs.75.3%±9.4%,P=0.036)and FCR(84.2%vs.55.1%,P=0.020)compared with good collateral group.Carotid NWI(OR=3.83,95%CI:1.36–10.82,P=0.011)and more FCR(OR=6.77,95%CI:1.35–33.85,P=0.020)were associated with poor collateral circulation after adjustment for the confounding factors.The combination of NWI,FCR,systolic blood pressure,and triglycerides had the highest area-under-the-curve(AUC=0.85)for detection of poor collaterals.Conclusions Carotid plaque features,specifically NWI and FCR,are independently associated with poor collateral circulation,and the combination of carotid plaque features and traditional risk factors has a stronger predictive value for poor collateral circulation than plaque features alone.

A comparison of carotid atherosclerosis in symptomatic patients between 2002-2005 and 2012-2015 cohorts using multi-contrast magnetic resonance vessel wall imaging

OBJECTIVE To compare the morphological and compositional characteristics of carotid plaques in two cohorts(2002−2005 and 2012−2015)of Chinese patients using magnetic resonance vessel wall imaging.METHODS Symptomatic patients with carotid atherosclerotic plaques who underwent carotid vessel wall magnetic resonance imaging between 2002−2005 and 2012−2015 were retrospectively recruited.Plaque morphology[including mean wall area,wall thickness,and maximum normalized wall index(NWI)]and composition[including calcification,intraplaque hemorrhage,and lipid-rich necrotic core(LRNC)]in symptomatic carotid arteries were evaluated and compared between patients in these two time periods.RESULTS A total of 258 patients,including 129 patients in the 2002−2005 cohort and 129 patients in the 2012−2015 cohort,were recruited.Statin use(49.6%vs.32.6%,P=0.004)and hypertension(76.0%vs.62.8%,P=0.015)were significantly more common in the 2012-2015 cohort than in the 2002−2005 cohort.Patients in the 2012−2015 cohort also exhibited significantly low plaque burden parameters(all P<0.05),as well as a lower prevalence(68.2%vs.89.9%,P<0.001)and volume percentages of LRNC(11.2%±14.2%vs.25.7%±17.7%,P<0.001).These differences remained significant after adjustment for clinical factors.The differences in the volume percentages of LRNC also remained significant after an additional adjustment for maximum NWI(P<0.001).CONCLUSIONS Patients in the 2012−2015 cohort had a lower plaque burden and volume percentages of LRNC in symptomatic carotid arteries than those in the 2002−2005 cohort.These findings indicate that carotid plaques in the recent cohort had a lower severity and vulnerability.