Co-existing cerebrovascular atherosclerosis predicts subsequent vascular event: a multi-contrast cardiovascular magnetic resonance imaging study

Histological Validation of 3D Variable Flip Angle TSE Multi-Contrast Magnetic Resonance Vessel Wall Imaging in Characterizing Carotid Vulnerable Atherosclerotic Plaques

BACKGROUND

Accurate assessment of the vulnerability of carotid atherosclerotic plaques is crucial for stroke prevention. The three-dimensional (3D) magnetic resonance (MR) vessel wall imaging (VWI) has been increasingly employed to evaluate carotid plaques due to its extensive coverage and isotropic high spatial resolution. However, the accuracy of such technique lacks validation by histology.

OBJECTIVE

This study aims to validate the accuracy of 3D multi-contrast MR VWI used variable-flip-angle (VFA) and turbo spin echo (TSE) readout in identifying vulnerable carotid plaques, using histological analysis as a reference.

METHODS

Twenty-one male patients (mean age: 64.4 ± 7.2 years) scheduled for carotid endarterectomy (CEA) were recruited for this study. All patients underwent carotid multi-contrast MR VWI, including 3D T1- and T2-weighted variable flip angle-based turbo spin echo (VFA-TSE) sequences, as well as 3D time of flight (TOF) MR angiography (MRA), using a 3.0T MR system. Histological processing was performed for carotid plaque specimens. The presence or absence, along with the area measurements, of lipid-rich necrotic core (LRNC), intraplaque hemorrhage (IPH), and calcifications (CA) were independently evaluated on both MR images and histological sections. Cohen's kappa (κ) analysis was utilized to determine the agreement between 3D multi-contrast MR VWI and histology in identifying carotid plaque compositions before and after excluding compositions bellow certain size threshold. Spearman's correlation analysis was also conducted to assess the agreement in quantifying plaque compositions.

RESULTS

A total of 81 slices of MR images were successfully matched with histological sections. Moderate to almost perfect agreements were observed between 3D MR VWI and histology in the identification of LRNC (κ: 0.85 and 0.89), IPH (κ: 0.65 and 0.69), and CA (κ: 0.46 and 0.62) before and after excluding compositions smaller than 0.79 mm2. Strong to very strong correlations were found in the quantification of plaque compositions including LRNC (r=0.88), IPH (r=0.80), and CA (r=0.74) between MR imaging and histology.

CONCLUSION

The 3D VFA-TSE multi-contrast MR VWI is capable of accurately characterizing vulnerable carotid atherosclerotic plaques.

Non-alcoholic fatty liver disease: A new predictor of recurrent ischemic stroke and transient ischemic attack in patients with carotid atherosclerosis

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. This study focused on assessing the predictive significance of NAFLD for recurrent stroke and transient ischemic attack (TIA) risk to determine the value of NAFLD.

METHOD

This study included 742 participants (mean age: 64.26 ± 9.42 years, 497 males) with carotid atherosclerosis who underwent carotid CT angiography (CTA) between January 2013 and December 2021 in this retrospective study. NAFLD was diagnosed by non-enhanced abdominal CT. The clinical endpoint was a recurrent ischemic stroke or TIA. Cox proportional hazards and Kaplan-Meier analysis assessed whether NAFLD was associated with the endpoint. We accessed the predictive values of NAFLD, clinical, plaque characteristics, and combined model by the C statistics. The predictive performance of the combined model was assessed by receiver operating characteristic curve (ROC) analysis.

RESULTS

A total of 742 participants (mean age: 64.26 ± 9.42 years, 497 males) were included. During 2.9 years of follow-up (interquartile range, 2.1-3.9), 166 patients reached the clinical endpoint. Multivariable cox analyses showed NAFLD was associated with recurrent stroke or TIA in all groups (all P<0.05). Patients with NAFLD had a lower event-free survival (EFS) rate than those without NAFLD (P<0.05). The combined model, including NAFLD, clinical data and plaque features, showed the best performance in predicting the clinical endpoint (AUC=0.79).

CONCLUSIONS

NAFLD contributes to the prediction of recurrent ischemic stroke or TIA. NAFLD may be a novel imaging marker that offers a new perspective on preventing cardiovascular disease in the clinic.

Associations between atherosclerotic luminal stenosis in the distal internal carotid artery and diffuse wall thickening in its upstream segment

OBJECTIVES

Significant atherosclerotic stenosis or occlusion in the distal internal carotid artery (ICA) may induce diffuse wall thickening (DWT) in the upstream arterial wall. This study aimed to assess the association of atherosclerotic steno-occlusive diseases in the distal ICA with DWT in the upstream ipsilateral ICA.

METHODS

Individuals with atherosclerotic stenosis in the distal ICA, detected by carotid MR vessel wall imaging using 3D pre- and post-contrast T1 volume isotropic turbo spin-echo acquisition (T1-VISTA) sequence, were enrolled. The associations of vessel wall thickening, the longitudinal extent of DWT, enhancement of the upstream ipsilateral ICA, and stenosis degree in the distal ICA were examined.

RESULTS

Totally 64 arteries in 55 patients with atherosclerotic steno-occlusive distal ICAs were included. Significant correlations were found between distal ICA stenosis and DWT in the petrous ICA (r = 0.422, p = 0.001), DWT severity (r = 0.474, p < 0.001), the longitudinal extent of DWT in the ICA (r = 0.671, p < 0.001), enhancement in the petrous ICA (r = 0.409, p = 0.001), and enhancement degree (r = 0.651, p < 0.001). In addition, high degree of enhancement was correlated with both increased wall thickness and increased prevalence of DWT in the petrous ICA (both p < 0.001).

CONCLUSIONS

DWT of the petrous ICA is commonly detected in patients with atherosclerotic steno-occlusive disease in the distal ICA. The degree of stenosis in the distal ICA is associated with wall thickening and its longitudinal extent in the upstream segments.

CLINICAL RELEVANCE STATEMENT

Diffuse wall thickening is a common secondary change in atherosclerotic steno-occlusive disease in the intracranial carotid. This phenomenon constitutes a confounding factor in the distinction between atherosclerosis and inflammatory vasculopathies, and could be reversed after alleviated atherosclerotic stenosis.

KEY POINTS

• Diffuse wall thickening of the petrous internal carotid artery is commonly detected in patients with atherosclerotic steno-occlusive disease in the distal internal carotid artery. • The phenomenon of diffuse wall thickening could be reversed after stenosis alleviation. • Carotid artery atherosclerosis with diffuse wall thickening should warrant a differential diagnosis from other steno-occlusive diseases, including moyamoya diseases and Takayasu aortitis.

Association of systemic inflammatory response index and plaque characteristics with the severity and recurrence of cerebral ischemic events

AIM

We aimed to investigate the relationship between systemic inflammatory response index (SIRI) and intracranial plaque features, as well as the risk factors related to the severity and recurrence of cerebral ischemic events.

METHODS

We enrolled 170 patients with cerebral ischemic events. Baseline demographic characteristics and laboratory indicators were collected from all participants. All patients were assessed by high-resolution magnetic resonance vessel wall imaging for culprit plaque characteristics and intracranial atherosclerotic burden. Outpatient or telephone follow-up were conducted at 1, 3, and 6 months after discharge.

RESULTS

SIRI levels were significantly associated with the enhanced plaque number (r = 0.205, p = 0.007), total plaque stenosis score (r = 0.178, p = 0.020), total plaque enhancement score (r = 0.222, p = 0.004), intraplaque hemorrhage (F = 5.630, p = 0.004), and plaque surface irregularity (F = 3.986, p = 0.021). Higher SIRI levels (OR = 1.892), total plaque enhancement score (OR = 1.392), intraplaque hemorrhage (OR = 3.370) and plaque surface irregularity (OR = 2.846) were independent risk factors for moderate-severe stroke, and these variables were significantly positively correlated with NIHSS (P < 0.05 for all). In addition, higher age (HR = 1.063, P = 0.015), higher SIRI levels (HR = 2.003, P < 0.001), and intraplaque hemorrhage (HR = 4.482, P = 0.008) were independently associated with recurrent stroke.

CONCLUSIONS

Higher SIRI levels may have adverse effects on the vulnerability and burden of intracranial plaques, and links to the severity and recurrence of ischemic events. Therefore, SIRI may provide important supplementary information for evaluating intracranial plaque stability and risk stratification of patients.

Peri-Carotid Adipose Tissue and Atherosclerosis at Carotid Bifurcation

Vulnerable carotid plaques are responsible for 20% of the ischemic strokes. The identification of these asymptomatic carotid plaques that will become symptomatic is essential but remains unclear. Our main goal was to investigate whether the amount of the peri-carotid adipose tissue, estimated by the extra-media thickness (EMT), is associated with the atherosclerotic characteristics at the carotid bifurcation in patients with PAD. An observational, prospective, single-center, longitudinal study was conducted. Overall, 177 patients were subjected to carotid Doppler ultrasound at the study admission. The following data were collected: EMT, intima-media thickness (IMT), the presence of carotid plaques, the area of the highest plaque, the presence of "acute culprit" carotid stenosis, and the grade of internal carotid stenosis. "Acute culprit" carotid stenosis was defined as a significant atherosclerotic plaque that leads to a neurologic event within 15 days. From each carotid bifurcation, a right and a left EMT were determined. We analyzed both the mean EMTs (calculated as the mean between the right and the left EMT) and the EMT ipsilateral to the carotid bifurcation. The presence of carotid plaques was associated with a higher mean EMT [Median = 1.14; IQR = 0.66 versus Median = 0.97; IQR = 0.40; p = 0.001]. A positive correlation was found between the mean EMT and IMT (right: ρ = 0.20; p = 0.010; left: ρ = 0.21; p = 0.007) and between the mean EMT and the area of the largest carotid plaque (right: ρ = 0.17; p = 0.036; left: ρ = 0.22; p = 0.004). Left carotid stenosis ≥ 70% was associated with higher ipsilateral EMT [Median = 1.56; IQR = 0.70 versus Median = 0.94; IQR = 0.42; p = 0.009]. Patients with "acute culprit" carotid stenosis had a higher ipsilateral EMT [left ipsilateral EMT: Median = 1.46; IQR = 0.63; "non-acute": Median = 0.94; IQR = 0.43; p = 0.009; right ipsilateral EMT: Median = 2.25; IQR = 0.62; "non-acute": Median = 1.00; IQR = 0.51; p = 0.015]. This difference was not found in the contra-lateral EMT. Six months after the neurologic event, EMT ipsilateral to an "acute culprit" carotid stenosis decreased (p = 0.036). The amount of peri-carotid adipose tissue, estimated with EMT, was associated with atherosclerosis at the carotid arteries. The mean EMT was associated with the features of chronic atherosclerosis lesions: the presence of carotid plaques, IMT, and the area of the highest plaque. Ipsilateral EMT was linked with "acute culprit" atherosclerotic plaque.

Comparison of short-term outcomes between patients with extracranial carotid and/or intracranial atherosclerotic disease

OBJECTIVE

To directly compare the 90-day outcomes of patients with symptomatic intracranial atherosclerotic disease (ICAD), extracranial carotid atherosclerotic disease (ECAD), and ICAD with concomitant ECAD.

METHODS

From 2017-2021, patients who had (1) a transient ischemic attack or ischemic stroke within 30 days of admission as evaluated by a stroke neurologist and (2) ipsilateral ICAD and/or ECAD were prospectively enrolled. The cohort was divided into three groups: ICAD, ECAD, and ICAD with concomitant ECAD. The primary outcome assessed was 90-day ischemic stroke recurrence. Secondary outcomes included 90-day myocardial infarction (MI), all-cause mortality, and major adverse cardiovascular events (MACE, including cardiovascular death, nonfatal MI, and/or nonfatal ischemic stroke).

RESULTS

Of 371 patients included in the analysis, 240 (64.7%) patients had ICAD only, 93 (25.0%) patients had ECAD only, and 38 (10.3%) patients had ICAD with concomitant ECAD. On multivariate time-to-event analysis adjusting for potential confounders and with ICAD as the reference comparator, the risk of 90-day clinical outcomes was highest among patients with ICAD and concomitant ECAD, with adjusted hazard ratios of 4.54 (95% CI=1.45, 14.2; p = 0.006), 9.32 (95% CI=1.58, 54.8; p = 0.014), and 8.52 (95% CI=3.54, 20.5; p < 0.001) for 90-day ischemic stroke, MI, and MACE, respectively.

CONCLUSIONS

Patients with ICAD and concomitant ECAD have a poorer prognosis and are at significantly higher risk for 90-day ischemic stroke, MI, and MACE. Further research should focus on the evaluation of coronary atherosclerotic disease and more intensive medical therapy in this population.

Co-existing intracranial and extracranial carotid atherosclerosis predicts large-artery atherosclerosis stroke recurrence: a single-center prospective study utilizing combined head-and-neck vessel wall imaging

OBJECTIVES

Intracranial and extracranial plaque features on high-resolution vessel wall imaging (HR-VWI) are associated with large-artery atherosclerosis (LAA) stroke recurrence. However, most studies have focused on a single vascular bed, and the prognostic value of combined intracranial and extracranial plaque features has yet to be studied. This study aimed to investigate the roles of plaque features, plaque number, and co-existing atherosclerosis in predicting stroke recurrence, utilizing combined head-and-neck HR-VWI.

METHODS

From September 2016 to March 2020, participants with acute LAA ischemic strokes were prospectively enrolled and underwent combined head-and-neck HR-VWI. The participants were followed for stroke recurrence for at least 12 months or until a subsequent event occurred. The imaging features at baseline, including conventional and histogram plaque features, plaque number, and co-existing atherosclerosis, were evaluated. Univariable Cox regression analysis and the least absolute shrinkage and selection operator (lasso) method were used for variable screening. Multivariable Cox regression analyses were used to determine the independent risk factors of stroke recurrence.

RESULTS

A total of 97 participants (59 ± 12 years, 63 men) were followed for a median of 30.9 months, and 21 participants experienced recurrent strokes. Multivariable Cox analysis identified co-existing intracranial high signal on T1-weighted fat-suppressed images (HST1) and extracranial carotid atherosclerosis (HR, 6.12; 95% CI, 2.52-14.82; p = 0.001) as an independent imaging predictor of stroke recurrence.

CONCLUSION

Co-existing intracranial HST1 and extracranial carotid atherosclerosis independently predicted LAA stroke recurrence. Combined head-and-neck HR-VWI is a promising technique for atherosclerosis imaging.

CLINICAL RELEVANCE STATEMENT

This prospective study using combined head-and-neck HR-VWI highlighted the necessity of both intracranial culprit plaque evaluation and multi-vascular bed assessment, adding value to the prediction of stroke recurrence.

KEY POINTS

• This study highlighted the necessity of both intracranial culprit plaque evaluation and multi-vascular bed assessment, adding value to the prediction of stroke recurrence. • This prospective study using combined head-and-neck HR-VWI found co-existing intracranial HST1 and extracranial carotid atherosclerosis to be independent predictors of stroke recurrence.

Differences in distribution and features of carotid and middle cerebral artery plaque in patients with pial infarction and perforating artery infarction: A 3D vessel wall imaging study

PURPOSE

Atherosclerotic plaques of carotid artery (CA) and middle cerebral artery (MCA) are important causes of acute ischemic stroke (AIS). This study was designed to jointly assess the plaque distribution and features of CA and MCA in AIS patients with pial infarction (PI) and perforating artery infarction (PAI), and to investigate the associations between plaque characteristics and ischemic infarction patterns.

METHODS

Imaging data of sixty-five patients from a cross-sectional study were reviewed. All the patients had acute infarction in the MCA territory on diffusion weighted imaging (DWI) and underwent CA and MCA vessel wall imaging (VWI). The CA and MCA plaque presence and high-risk features on the ipsilateral side of infarction were analyzed. The brain infarction lesions were divided into PI group vs. non-PI group, and PAI group vs. non-PAI group. Different plaque distribution types and plaque features were compared in each two groups, and their associations were investigated using binary logistic regression.

RESULTS

Sixty-five patients (mean age, 54.6 ± 10.1 years; 61 men) were included. The CA high-risk plaque (OR: 5.683 [1.409-22.929], P = 0.015) and MCA plaque presence (OR: 3.949 [1.397-11.162], P = 0.010) were significantly associated with PI. MCA plaques that involved the orifice of the perforating arteries were significantly associated with PAI (OR: 15.167 [1.851-124.257], P = 0.011).

CONCLUSION

CA and MCA plaques show distinct distribution and high-risk features in patients with PI and PAI. Combined intracranial and extracranial arteries imaging should be considered for the evaluation of the symptomatic ischemic patients.

Systematic Review on Magnetic Resonance Angiography with Vessel Wall Imaging for the Characterization of Symptomatic Carotid Artery Plaque

BACKGROUND

To perform a systematic literature review to assess the usefulness of performing magnetic resonance angiography (MRA) with vessel wall imaging (VWI) sequences for the assessment of symptomatic carotid artery plaques and the identification of risky plaque features predisposing for stroke.

METHODS

We performed a systematic review of the literature pertaining to MRA with VWI techniques in patients with carotid artery disease, focusing on symptomatic patients' plaque features and morphology. Independent reviewers screened and analyzed data extracted from eligible studies, and a modified Newcastle-Ottawa Scale was used to appraise the quality of the design and content of the selected manuscripts to achieve an accurate interpretation.

RESULTS

This review included nineteen peer-reviewed manuscripts, all of them including MRA and VWI assessments of the symptomatic carotid artery plaque. We focused on patients' comorbidities and reviewed plaque features, including intraplaque hemorrhage, a lipid-rich necrotic core, a ruptured fibrous cap, and plaque ulceration.

CONCLUSIONS

MRA with VWI is a useful tool in the evaluation of carotid artery plaques. This imaging technique allows clinicians to identify plaques at risk of causing a neurovascular event. The presence of intraplaque hemorrhage, plaque ulceration, a ruptured fibrous cap, and a lipid-rich necrotic core are associated with neurovascular symptoms. The timely identification of these features could have a positive impact on neurovascular event prevention.

Demographic and risk factors profile of intracranial atherosclerotic stenosis in the Kingdom of Bahrain

Background

Intracranial atherosclerotic stenosis (ICAS) is one of the most common causes of stroke worldwide. This study aimed to analyze the demographic and risk factor profiles of ICAS in the Kingdom of Bahrain. The study population included 477 patients who were hospitalized in the Neurology Department from March 1, 2018, to September 1, 2020 because of acute ischemic stroke and underwent arterial brain imaging (CTA or MRA) examination during their hospitalization.

Results

Of 477 patients, 123 (25.7%) had ICAS. A history of stroke/transient ischemic attack was significantly higher in patients with intracranial stenosis (P = 0.012). Patients with ICAS had significant concurrent extracranial arterial stenosis (ECAS) (P = 0.00). In Bahraini patients, dyslipidemia was associated with a higher percentage of developing ICAS, but this was statistically nonsignificant (p = 0.06).

Conclusions

An independent and significant correlation was found between ICAS and stroke recurrence. In addition, a concurrent existence of ECAS and ICAS was noted.

Predictive value of the combination between the intracranial arterial culprit plaque characteristics and the Essen Stroke Risk Score for short-term stroke recurrence

AIM

In the current study we aim the identification of the culprit plaque characteristics of intracranial arteries using high-resolution magnetic resonance vessel wall imaging (HR-MR-VWI). Moreover, we target the evaluation of the predictive value of culprit plaque characteristics for short-term stroke recurrence combined with ESRS.

MATERIALS AND METHODS

We conducted a prospective cohort study on 342 patients diagnosed with symptomatic intracranial atherosclerotic stenosis (sICAS), out of which 243 were men and 99 were women with an average age of 64 ± 12 years. 184 cases of anterior circulation ischemia (ACIS) and 158 cases of posterior circulation ischemia (PCIS) were included in the study. All of them underwent HR-MR-VWI during the period between February 2020 and June 2021 in the Second Affiliated Hospital of Nantong University, Nantong, China. The culprit vessel and culprit plaque characteristics were assessed based on HR-MR-VWI images, and the patients' ESRS were obtained from the electronic medical records of the hospital. Concerning the obtained results from the 6-month follow-up, the patients were divided into the non-recurrence group and the recurrence group, and the differences in the above-mentioned features between the two groups were compared. The univariate Cox regression analysis combined with ESRS was performed to screen out the independent risk factors associated with recurrent stroke with P < 0.1. Receiver operating characteristic curves (ROC curves) were plotted to analyze the predictive performance of the culprit plaque characteristics, ESRS and combined variables for stroke recurrence. We used the area under the curve (AUC) ROC, while the sensitivity and specificity were calculated at the optimal threshold. The Delong test was employed to compare the quality of the AUC of the predictors.

RESULTS

A total of 15.5% (53/342) of patients had a stroke recurrence within six months, with statistically significant differences (P < 0.05) between the two groups regarding the ESRS, medical history of diabetes mellitus, myocardial infarction, data for previous acute ischemic stroke (AIS) or transient ischemic attack(TIA), history of peripheral vascular disease, and serum brain natriuretic peptide level. In the patients with ACIS, the incidence of hyperintensity on the T1-weighted imaging (T1WI) was significantly different between the recurrence and the non-recurrence groups (P < 0.05). In the patients with PCIS, statistically significant differences between the recurrence and the non-recurrence group were detected in the culprit plaque burden, degree of enhancement, and incidence of hyperintensity on T1WI (P < 0.05). The ESRS (hazard ratios [HR], 1.598, 95% confidence interval [CI], 1.193-2.141, P = 0.002) ,degree of enhancement (HR = 1.764, 95% CI 0.985-3.087, P = 0.047) and hyperintensity on T1WI (HR = 2.745, 95% CI 1.373-5.488, P = 0.004) proved to be independent risk factors for stroke recurrence. The ESRS predicted stroke recurrence with AUC = 0.618 (95% CI 0.564-0.670), while the best cut-off value was 2 points. Furthermore, the registered sensitivity and specificity were 60.4% and 58.5%, respectively. Regarding the degree of enhancement in the culprit plaque, the prediction of stroke recurrence was with AUC = 0.628 (95% CI 0.574-0.679) as well as with sensitivities and specificities of 58.5% and 64.4%, respectively. Regarding the hyperintensity on T1WI in culprit plaque, the prediction of stroke recurrence was with AUC = 0.678 (95% CI 0.626-0.727) as well as with sensitivities and specificities of 66.0% and 70.0%, respectively. The ESRS combined with the degree of enhancement predicted stroke recurrence with an AUC = 0.685 (95CI% 0.633-0.734), while the recorded sensitivity and specificity were 56.6% and 73.4%, respectively. The ESRS combined with hyperintensity on the T1WI predicted stroke recurrence with an AUC = 0.745 (95CI% 0.696-0.791). The recorded sensitivity and specificity were 64.2% and 76.8%, respectively. The AUC quality of the ESRS combined with hyperintensity on T1WI was higher than that of other indices (P < 0.05).

CONCLUSIONS

The hyperintensity on T1WI of the culprit plaque in intracranial arteries combined with ESRS demonstrated better predictive ability for short-term stroke recurrence. We consider this of high importance for clinical application since it provides an easier way of obtaining data for precise diagnosis.

Correlation of the characteristics of symptomatic intracranial atherosclerotic plaques with stroke types and risk of stroke recurrence: a cohort study

Background

Symptomatic intracranial atherosclerotic stenosis (sICAS) patients had a higher risk of stroke recurrence, and the risk of acute ischemic stroke (AIS) was higher than transient ischemic attack (TIA). Therefore, it is important to explore the risk factors associated with sICAS clinical subtypes and the risk of stroke recurrence. The purpose of this study was to investigate the association between intracranial arterial culprit plaque characteristics with sICAS clinical subtypes and the risk of stroke recurrence.

Methods

A total of 206 patients with sICAS were included. Baseline demographic data and relevant serologic indices were collected from all participants. All participants were assessed by high-resolution vessel wall imaging (HR-VWI) for culprit vessel and culprit plaque characteristics. The follow-up method was outpatient or telephone follow-up. Associated factors for sICAS clinical subtypes were analyzed by binary logistic regression. Cox proportional hazard regression analysis were used to analysis the independent risk factors for recurrent stroke.

Results

In this group, there were 154 patients with AIS, 52 patients with TIA, 124 patients with anterior circulation ischemic symptom (ACiS), and 82 patients with posterior circulation ischemic symptom (PCiS). Male gender [odds ratio (OR) =5.575, 95% confidence interval (CI): 2.120 to 14.658], history of previous statin use (OR =0.309, 95% CI: 0.113 to 0.843) and serum apolipoprotein A/B values (OR =0.363, 95% CI: 0.139 to 0.948) were associated factors for AIS. A total of 24 patients (11.7%) experienced stroke recurrence during the 1-year follow-up period. Hyperintensity on T1 weighted imaging (T1WI) in the culprit plaque [hazard ratio (HR) =3.798, 95% CI: 1.433 to 10.062] was an independent risk factor for stroke recurrence. The incidence of significant enhancement (62.2% vs. 39.5%, χ²=9.681, P=0.002), positive remodeling (69.5% vs. 52.4%, χ²=5.661, P=0.020), and hyperintensity on T1WI (42.7% vs. 22.6%, χ²=16.472, P=0.003) was higher in the posterior circulation than in the anterior circulation.

Conclusions

The characteristics of intracranial arterial culprit plaques were independent risk factors for recurrent stroke, and there were differences in the plaque characteristics of anterior and posterior circulation. Early HR-VWI examination for sICAS patients is of great significance for patient risk stratification and personalized management.

Intracranial Atherosclerotic Plaque Characteristics and Burden Associated With Recurrent Acute Stroke: A 3D Quantitative Vessel Wall MRI Study

Background: Intracranial atherosclerotic disease (ICAD) tends to affect multiple arterial segments, and previous studies rarely performed a comprehensive plaque analysis of the entire circle of Willis for the evaluation of recurrent stroke risk. We aimed to investigate the features of circle of Willis ICAD on 3D magnetic resonance vessel wall imaging (MR-VWI) and their relationships with recurrent acute stroke. Methods: Patients with either acute ischemic stroke (within 4 weeks after stroke) or chronic ischemic stroke (after 3 months of stroke) due to intracranial atherosclerotic plaque underwent 3D contrast-enhanced MR-VWI covering major cerebral arteries. Participants were divided into three groups: first-time acute stroke, recurrent acute stroke, and chronic stroke. Culprit plaque (defined as the only lesion or the most stenotic lesion when multiple plaques were present within the same vascular territory of the stroke) and non-culprit plaque characteristics, including total plaque number, plaque thickness, plaque area, plaque burden (calculated as plaque area divided by outer wall area), enhancement ratio (ER), eccentricity, and stenosis, were measured and compared across the three groups. Associations between plaque characteristics and recurrent acute stroke were investigated by multivariate analysis. Results: A total of 176 participants (aged 61 ± 10 years, 109 men) with 702 intracranial plaques were included in this study. There were 80 patients with first-time acute stroke, 42 patients with recurrent acute stroke, and 54 patients with chronic stroke. More intracranial plaques were found per patient in the recurrent acute stroke group than in the first-time acute stroke or chronic stroke group (5.19 ± 1.90 vs. 3.71 ± 1.96 and 3.46 ± 1.33, p < 0.001). Patients in the recurrent acute stroke group had greater culprit plaque burden (p < 0.001) and higher culprit ER (p < 0.001) than the other two groups. After adjustment of clinical demographic factors, in multivariate analysis, coronary artery disease (CAD) (odds ratio, OR = 4.61; p = 0.035), total plaque number (OR = 1.54; p = 0.003), culprit plaque ER (OR = 2.50; p = 0.036), and culprit plaque burden (OR per 10% increment = 2.44; p = 0.010) were all independently associated with recurrent acute stroke compared to the first-time acute stroke. Conclusion: Increased intracranial atherosclerotic plaque number, higher culprit plaque ER, greater culprit plaque burden, and CAD are independently associated with recurrent acute stroke.

Carotid intraplaque neovascularisation as a predictive factor for future vascular events in patients with mild and moderate carotid stenosis: an observational prospective study

Background:

Intraplaque neovascularisation (IPN) increases the vulnerability of plaques, which makes them more likely to rupture and increases the risk of vascular events. However, it is unclear whether IPN can predict future vascular events (stroke recurrence and cardiovascular events). Previous studies on IPN have focused on patients with severe stenosis but overlooked patients with mild and moderate stenosis. This study aimed to investigate whether IPN assessed by contrast-enhanced ultrasonography (CEUS) in patients with mild and moderate degrees of stenosis is associated with future vascular events.

Methods:

One hundred and twenty-one patients participated in this study. 76 patients who met the inclusion and exclusion criteria were included in the final dataset of the study. IPN was graded from 0 to 2 according to the extent of the microbubbles assessed using CEUS. The degree of carotid stenosis was graded as mild, moderate, or severe. We recorded future vascular events during the follow-up. Univariate and multivariate logistic regression analyses were used to evaluate risk factors for future vascular events.

Results:

After a follow-up period of 30 ± 6 months, 30 patients (39.5%) experienced subsequent vascular events. Compared with the ‘non-recurrent’ group, the ‘recurrent’ group showed a higher proportion of grade 2 neovascularisation (p < 0.05), and it was an independent predictor of subsequent vascular events (odds ratio 6.066, 95% confidence interval 1.565–23.512, p < 0.05). Furthermore, in patients with mild and moderate stenosis, future vascular events occurred in an unexpectedly high proportion (up to 42.9%). In the ‘recurrent’ group, 55% of patients with mild and moderate stenosis had grade 2 neovascularisation.

Conclusion:

IPN by CEUS was an independent predictor of future vascular events in patients with recent ischemic stroke, and the high proportion of neovascularisation in patients with mild and moderate stenosis requires more attention.

Association between coexisting intracranial artery and extracranial carotid artery atherosclerotic diseases and ipsilateral cerebral infarction: a Chinese Atherosclerosis Risk Evaluation (CARE-II) study

BACKGROUND

To evaluate the association between coexisting intracranial and extracranial carotid artery atherosclerotic diseases and ipsilateral acute cerebral infarct (ACI) in symptomatic patients by using magnetic resonance (MR) vessel wall imaging.

METHODS

Symptomatic patients were recruited from a cross-sectional, multicentre study of Chinese Atherosclerosis Risk Evaluation (CARE-II). All patients underwent MR imaging for extracranial carotid arterial wall, intracranial artery and brain. Coexisting intracranial stenosis ≥50% and extracranial carotid artery mean wall thickness (MWT) ≥1 mm and plaque compositions at the same side were evaluated and the ipsilateral ACI was identified. The association between coexisting atherosclerotic diseases and ACI was evaluated using logistic regression.

RESULTS

351 patients were recruited. Patients with ipsilateral ACI had significantly greater prevalence of coexisting intracranial stenosis ≥50% and carotid MWT ≥1 mm (20.5% vs 4.9%, p<0.001), calcification (15.1% vs 4.4%, p=0.001) and lipid-rich necrotic core (LRNC) (19.2% vs 7.8%, p=0.002) compared with those without. Coexisting intracranial artery stenosis ≥50% and carotid MWT ≥1 mm (OR 5.043, 95% CI 2.378 to 10.694; p<0.001), calcification (OR 3.864, 95% CI 1.723 to 8.664; p=0.001) and LRNC (OR 2.803, 95% CI 1.455 to 5.401; p=0.002) were significantly associated with ipsilateral ACI. After adjusting for confounding factors, the aforementioned associations remained statistically significant (intracranial stenosis ≥50% coexisting with carotid MWT ≥1 mm: OR 4.313, 95% CI 1.937 to 9.601, p<0.001; calcification: OR 3.606, 95% CI 1.513 to 8.593, p=0.004; LRNC: OR 2.358, 95% CI 1.166 to 4.769, p=0.017).

CONCLUSIONS

Coexistence of intracranial artery severe stenosis and extracranial carotid artery large burden and intraplaque components of calcification and LRNC are independently associated with ipsilateral ACI.

TRIAL REGISTRATION NUMBER

https://www.clinicaltrials.gov/. Unique identifier: NCT02017756.

Progression of Plaque Burden of Intracranial Atherosclerotic Plaque Predicts Recurrent Stroke/Transient Ischemic Attack: A Pilot Follow-Up Study Using Higher-Resolution MRI

BACKGROUND

Patients with intracranial atherosclerotic disease (ICAD) have a high frequency of stroke recurrence. However, there has been little investigation into the prognostic value of higher-resolution magnetic resonance imaging (HR-MRI).

PURPOSE

To investigate the use of intracranial atherosclerotic plaques features in predicting risk of recurrent cerebrovascular ischemic events using HR-MRI.

STUDY TYPE

Prospective.

POPULATION

Fifty-eight patients with acute/subacute stroke (N = 46) or transient ischemic attack (N = 12).

FIELD STRENGTH/SEQUENCE

A 3.0 T, 3D time-of-flight gradient echo sequence and T1- and T2-weighted fast spin echo sequences with 0.31 x 0.39 mm² in-plane resolution, twice (with >3 months between scans) following the initial event.

ASSESSMENT

Patients were also followed clinically for recurrent ischemic events for up to 48 months or until a subsequent event occurred. The degree of stenosis, plaque burden (PB), minimal lumen area (MLA), and contrast enhancement ratio were assessed at each scanning session and the percentage change of each over time was calculated.

STATISTICAL TESTS

Univariable and multivariable Cox regression analyses were used to calculate the hazard ratio (HR) and 95% confidence interval (CI) for predicting recurrent events.

RESULTS

The mean time interval between baseline and follow-up MRI scans was 6.2 ± 4.1 months. After the second MRI scan, 20.7% of patients (N = 12) had experienced ipsilateral recurrent TIA/stroke within 10.9 ± 9.2 months. Univariable analyses showed that baseline triglyceride, percentage change of PB, and progression of PB were significantly associated with recurrent events (all P < 0.05). Multivariable Cox regression indicated that progression of PB (HR, 6.293; 95% CI, 1.620-24.444; P < 0.05) was a significant independent imaging feature for recurrent ischemic events.

DATA CONCLUSION

Progression of PB was independently associated with recurrent ischemic cerebrovascular events. HR-MRI may help risk stratification of patients at risk of recurrent stroke.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 4.

T-Configuration Stent Placement for Carotid Bifurcation Stenosis Co-Existing with Ipsilateral Intracranial Stenosis: A Case Report and Literature Review

In patients with carotid bifurcation stenosis co-existing with ipsilateral intracranial artery stenosis, combined treatment with carotid artery stenting (CAS)/carotid endarterectomy (CEA) and extracranial-to- intracranial (EC-IC) bypass can be a useful option to prevent future ischemic stroke events. EC-IC bypass requires a sufficient antegrade flow in the ipsilateral external carotid artery. However, standard CAS/CEA occasionally lead to external carotid artery occlusion. Herein, we present a case of successful one-stage endovascular revascularization of both the antegrade internal and external carotid artery flow using the carotid T-stent technique for carotid bifurcation stenosis co-existing with ipsilateral middle cerebral artery stenosis.

Concurrent intracranial and extracranial artery stenosis and the prognosis of transient ischaemic symptoms or imaging-negative ischaemic stroke

BACKGROUND AND PURPOSE

Transient ischaemic attack (TIA), transient symptoms with infarction (TSI) and diffusion-weighted imaging (DWI)-negative acute ischaemic stroke (AIS) share similar aetiologies but are considered to have a rather benign prognosis. We intended to investigate the association between intracranial atherosclerotic stenosis (ICAS), extracranial atherosclerotic stenosis (ECAS) and the prognosis of patients with TIA, TSI and DWI-negative AIS.

METHODS

Clinical and imaging data of eligible participants were derived from the Chinese Intracranial Atherosclerosis study, according to symptom duration, acute infarction on DWI and discharge diagnosis. Based on the severity and location of arterial atherosclerosis, we categorised the study population into four groups: no or <50% ICAS and no ECAS; ≥50% ICAS but no ECAS; no or <50% ICAS with ECAS; and concurrent ≥50% ICAS and ECAS. Using multivariable Cox regression models, we analysed the relationship between the severity and distribution of large artery atherosclerosis and the prognosis of TIA, TSI and DWI-negative AIS.

RESULTS

A total of 806 patients were included, 67.3% of whom were male. The median age of the study participants was 63 years. Patients in the concurrent ≥50% ICAS and ECAS subgroup had both a significantly higher 1-year recurrence rate (adjusted HR 3.4 (95% CI 1.15 to 10.04), p=0.027) and a higher risk of composite vascular events (adjusted HR 3.82 (95% CI 1.50 to 9.72), p=0.005).

CONCLUSIONS

Concurrent ICAS and ECAS is associated with a higher possibility of 1-year recurrent stroke or composite vascular events. Large artery evaluation is necessary to assess patients with transient ischaemic symptoms or DWI-negative AIS. Progress in shortening the time interval between symptom onset and large vessel evaluation is needed.