Symptomatic Carotid Endarterectomy Trial Criteria Research Articles

Risk factors of internal carotid artery stenosis in patients with proliferative diabetic retinopathy: an analysis using optical coherence tomography and optical coherence tomography angiography

BackgroundThis research investigates the correlation between the severity of internal carotid artery (ICA) stenosis and retinal parameters in patients with proliferative diabetic retinopathy (PDR), aiming to uncover potential risk factors.MethodsA retrospective analysis of 68 patients (136 eyes) diagnosed with bilateral PDR from January 1, 2017, to December 31, 2021, was conducted. Carotid artery stenosis (CAS) was assessed using neck computed tomography angiography (CTA) and carotid duplex ultrasound (CDUS), with stenosis classified into two groups: normal (group 1) and mild or above (group 2), based on the North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria. Optical coherence tomography (OCT) and OCT angiography (OCTA) measured several retinal parameters, including sub foveal choroidal thickness (SFCT), retinal nerve fiber layer (RNFL) thickness, ganglion cell-inner plexiform layer (GCIPL) thickness, vessel density (VD), and foveal avascular zone (FAZ) area. Statistical analyses determined correlations between ICA degrees and retinal parameters.ResultsThis study showed significant differences between groups in total VD, FAZ area, total RNFL thickness, and temporal RNFL thickness, indicating that patients with more severe ICA stenosis had noticeable retinal changes. Other parameters such as hyperlipidemia, total cholesterol levels, and intraocular pressure (IOP) also differed significantly, while no notable differences were observed in SFCT, central VD, average GCIPL, and superior, nasal, and inferior RNFL thickness.ConclusionThe study findings highlight retinal changes, such as an increased FAZ area, decreased total VD, and a total and thinner temporal RNFL, which suggest the need for carotid artery evaluation in patients. These findings have important clinical implications for the need for carotid work up in patients with PDR.

Carotid Artery Stenting for Heavily Calcified Lesions Using a Scoring Balloon: A Report of 2 Cases

Objective Carotid artery stenting for heavily calcified lesions is challenging for interventionists. A calcium burden is associated with suboptimal dilatation, periprocedural complications, high rates of restenosis, and poor outcomes. We describe the first report of 2 cases of successful carotid artery stenting for heavily calcified lesions using a scoring balloon. Case Presentation The patients were both aged 75 years, 1 male and 1 female, who had experienced ipsilateral stroke prior to the procedures. They had dense calcifications at the lesions, stenosis rates of 95% (near occlusion) and 86% according to the North American Symptomatic Carotid Endarterectomy Trial criteria, and calcification arcs of 270° and 360°, respectively. Considering the heavy calcification, predilation with scoring balloons (NSE PTA balloon; Nipro, Osaka, Japan) at the rated burst pressure was performed in both cases. Sufficient dilatation was achieved, followed by carotid stent deployment (Precise Pro RX; Cordis, Miami Lakes, FL, USA). After postdilatation, the stenosis rates decreased to 21% and 23%, respectively. Although 1 patient experienced prolonged bradycardia and hypotension, they were well managed with anticholinergic and vasoconstrictive agents. Both patients remained asymptomatic. Conclusion Carotid artery stenting using a scoring balloon obtained acceptable improvements in severe stenosis with heavily calcified lesions. This method could be a useful option for the revascularization of heavily calcified lesions.

Complications and outcomes of carotid artery stenting in high-risk cases

ObjectivesCarotid artery stenting is sometimes adapted for some at-risk cases; however, appropriate treatment timing with stroke onset is controversial. This study aims to identify factors that have an impact on complications and outcomes, especially in patients at high risk. Materials and MethodsWe examined the characteristics of 152 consecutive patients treated by carotid artery stenting between January 2018 and March 2022 and retrospectively analyzed the risk factors for complications and poor outcomes (modified-Rankin-Scale deterioration), such as patient background, carotid artery stenting risks (access route tortuosity, severe calcification, vulnerable plaque, estimated glomerular filtration rate <30 mL/min/1.73 m2, etc.), characteristics of the stenosis, details of treatment, and treatment timing. ResultsThe average North American Symptomatic Carotid Endarterectomy Trial criteria score was 68.3% and the lesion length was 20.5±9.7mm. Among patients, 107 (70.4%) had a carotid artery stenting risk. In high-risk carotid artery stenting cases, symptomatic complications occurred in 32 (30.0%), and the 90-day modified Rankin scale score deteriorated in 15 cases (14.0%). Multivariate analysis showed that cases with triple antithrombotic therapy (p=0.003), stenting within 7 days (p=0.0032), and after 28+ days (p=0.0035) of stroke onset were independently associated factors for complications. ConclusionsThis study showed that among risk factors, triple antithrombotic therapy in particular was a risk factor for perioperative complications. Carotid artery stenting for patients with stroke after 28 days of onset affects the prognosis. Therefore, although further study is warranted, waiting more than one month for treatment in patients requiring carotid artery stenting is a potential risk.

Impact of calcified plaque volume on technical and 3-year outcomes after transcarotid artery revascularization

ObjectiveWe sought to quantify the percent calcification within carotid artery plaques and assess its impact on percent residual stenosis and rate of restenosis in patients undergoing transcarotid artery revascularization for symptomatic and asymptomatic carotid artery stenosis. MethodsA retrospective review of prospectively collected institutional Vascular Quality Initiative data was performed to identify all patients undergoing transcarotid artery revascularization from December 2015 to June 2021 (n = 210). Patient and lesion characteristics were extracted. Using a semiautomated workflow, preoperative computed tomography head and neck angiograms were analyzed to determine the calcified plaque volume in distal common carotid artery and internal carotid artery plaques. Intraoperative digital subtraction angiograms were reviewed to calculate the percent residual stenosis post-intervention according to North American Symptomatic Carotid Endarterectomy Trial criteria. Peak systolic velocity and end-diastolic velocity were extracted from outpatient carotid duplex ultrasound examinations. Univariate logistic regression was performed to analyze the relationship of calcium volume percent and Vascular Quality Initiative lesion calcification to percent residual stenosis in completion angiograms. Kaplan-Meier analysis examined the relationship between calcium volume percent and in-stent stenosis over 36 months. ResultsOne hundred ninety-seven carotid arteries were preliminarily examined. Predilation was performed in 87.4% of cases with a mean balloon diameter of 5.1 ± 0.7 mm and a mean stent diameter was 8.8 ± 1.1 mm. The mean calcium volume percent was 11.9 ± 12.4% and the mean percent residual stenosis was 16.1 ± 15.6%. Univariate logistic regression demonstrated a statistically significant difference between calcium volume percent and percent residual stenosis (odds ratio [OR], 1.324; 95% confidence interval [CI], 1.005-1.746; P = .046). Stratified by quartile, only the top 25% of calcified plaques (>18.7% calcification) demonstrated a statistically significant association with higher percent residual stenosis (OR, 2.532; 95% CI, 1.049-6.115; P =.039). There was no statistical significance with lesion calcification (OR, 1.298; 95% C,: 0.980-1.718; P = .069). A Kaplan-Meier analysis demonstrated a statistically significant increase in the rate of in-stent stenosis during a 36-month follow-up for lesions containing >8.2% calcium volume (P = .0069). ConclusionsA calcium volume percent of >18.7% was associated with a higher percent residual stenosis, and a calcium volume percent of >8.2% was associated with higher in-stent stenosis at 36 months. There was one clinically diagnosed stroke during the follow-up period, demonstrating the overall safety of the procedure.

Clinical Application of High-Frame-Rate Vector Flow Imaging in Evaluation of Carotid Atherosclerotic Stenosis.

This study seeks to evaluate the value of the high-frame-rate vector flow imaging technique in assessing the hemodynamic changes of carotid atherosclerotic stenosis in aging people (>60 years old). Aging patients diagnosed with carotid atherosclerotic stenosis who underwent carotid high-frame-rate vector flow imaging examination were prospectively enrolled. A Mindray Resona7s ultrasound machine equipped with high-frame-rate vector flow function was used for ultrasound evaluation. First, B mode ultrasound and color Doppler flow imaging were used to evaluate carotid stenosis. Then, the vector arrows and flow streamline detected by V Flow were analyzed and the wall shear stress values (Pa) at the carotid stenosis site were measured. All patients were divided into symptomatic and asymptomatic groups according to whether they had acute/subacute stroke or other clinical symptoms within 2 weeks before ultrasound examination. The results of digital subtraction angiography or computed tomography angiography were used as the gold standard. The stenosis rate was calcified, according to North American Symptomatic Carotid Endarterectomy Trial criteria. The diagnostic values of wall shear stress, conventional ultrasound, and the combined diagnosis in carotid atherosclerotic stenosis were compared. Finally, 88 patients with carotid atherosclerotic plaque were enrolled (71 males (80.7%), mean age 67.6 ± 5.4 years). The success rate of high-frame-rate vector flow imaging was 96.7% (88/91). The WSS value of symptomatic carotid stenosis (1.4 ± 0.15 Pa) was significantly higher than that of asymptomatic carotid stenosis (0.80 ± 0.08 Pa) (p < 0.05). Taking the wall shear stress value > 0.78 Pa as the diagnostic criteria for symptomatic carotid atherosclerotic plaque, the area under receiver operating characteristic curves was 0.79 with 87.1% sensitivity and 69.6% specificity. The area under receiver operating characteristic curves of the combined diagnosis (0.966) for differentiating severe carotid atherosclerotic stenosis was significantly higher than that of conventional ultrasound and WSS value, with 89.7% sensitivity and 93.2% specificity (p < 0.05). As a non-invasive imaging method, the high-frame-rate vector flow imaging technique showed potential value in the preoperative assessment of the symptomatic carotid atherosclerotic stenosis and diagnosing carotid atherosclerotic stenosis in aging patients.

Vascular Imaging Follow‐Up in Carotid Webs: Is There Vascular Remodeling?

Vascular Imaging Follow‐Up in Carotid Webs: Is There Vascular Remodeling?

High-Frame Rate Vector Flow Imaging Technique: Initial Application in Evaluating the Hemodynamic Changes of Carotid Stenosis Caused by Atherosclerosis.

Objective: To investigate the value of high-frame rate vector flow imaging technique (V flow) in evaluating the hemodynamic changes of carotid stenosis caused by atherosclerotic plaques.Methods and Materials: In this prospective study, patients with stenosis rate (diameter) ≥30% caused by carotid atherosclerotic plaques were included. Degrees of carotid stenosis were graded according to North American Symptomatic Carotid Endarterectomy Trial criteria: moderate (30–69%) or severe (70–99%). Mindray Resona 7s ultrasound machine with a linear array transducer (3–11 MHz) was used for ultrasound examinations. The mean WSS value of carotid arteries was measured at the proximal, narrowest region and distal of carotid stenosis. The mean WSS values were correlated with peak systolic velocity (PSV) measured by color Doppler flow imaging and stenosis degree detected by digital subtraction angiography (DSA). The vector arrows and flow streamline detected by V flow dynamic imaging were analyzed. Imaging findings of DSA in carotid arteries were used as the gold standard.Results: Finally, 51 patients were included. V flow measurements were performed successfully in 17 patients (100%) with moderate-grade stenosis and in 30 patients (88.2%) with severe-grade stenosis. Dynamic V flow imaging showed yellow or red vectors at the stenotic segment, indicating fast speed blood flow (up to 260.92 cm/s). Changes of streamlines were detected in the stenotic segment. The mean WSS value measured at the narrowest region of the carotid artery had a moderately positive correlation with stenosis degree (r = 0.58, P < 0.05) and PSV value (r = 0.54, P < 0.05), respectively. Significant difference was detected in mean WSS value at the narrowest region of the carotid artery between severe carotid stenosis (1.47 ± 0.97 Pa) and moderate carotid stenosis (0.96 ± 0.44 Pa) (P < 0.05).Conclusion: The hemodynamic changes detected by V flow of the carotid stenosis might be a potential non-invasive imaging tool for assessing the degree of carotid stenosis.

Intravascular Lithotripsy During Transcarotid Artery Revascularization: A Novel Approach to Highly Calcified Lesions in High-Risk Patients

Introduced in 2009, transcarotid artery revascularization (TCAR) with flow reversal offers a less invasive option for carotid revascularization in high-risk surgical patients. In comparing in-hospital outcomes, TCAR had stroke/death/myocardial infarction rates similar to those of open CEA despite older and substantially higher risk patients (Schermerhorn et al, 2020). Compared with transfemoral stenting, TCAR had significantly lower in-hospital TIA/stroke/death rates despite a population with significantly more comorbidities (Malas et al, 2019). A relative contraindication to use of TCAR and carotid stenting in general is heavily calcified target lesions and lesions with circumferential calcification. Intravascular lithotripsy (IVL) has been introduced and approved for use in coronary artery and lower extremity arterial disease for endovascular treatment of heavily calcified lesions. IVL generates a sonic pressure wave that interacts with calcium, creating sheer stress that fractures the calcium. The objective of the study was to apply IVL to heavily calcified carotid lesions undergoing treatment with TCAR in high-risk surgery patients. This study represents a multicenter case series of seven patients undergoing TCAR with circumferential calcification of the target lesion. Treatment included off-label/off-instructions for use predilation or postdilation using IVL. Patients treated were considered high risk for carotid endarterectomy secondary to medical comorbidities in all cases. The primary end point was procedural success plus the absence of stroke in the immediate and 30-day postoperative period. The secondary end point was an improvement in the target lesion stenosis by North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria and nonsignificant (<50%) residual stenosis on follow-up imaging. Technical success was achieved in all cases. No patient suffered a stroke in the immediate or 30-day postoperative period. No cranial nerve abnormality, hematoma, wound infection, or other procedural complications was reported in the immediate postoperative period or at the first follow-up visit. By NASCET criteria, all patients had improvement in the target lesion stenosis, with all having nonsignificant stenosis on follow-up imaging. Dilation with IVL during TCAR is shown herein to be applicable safely without neurologic consequence in seven patients and has proved to be a technically feasible option in patients with extensive calcification of the target lesion. A larger study is needed to confirm the safety of applying IVL in the carotid vasculature in conjunction with TCAR. and longer follow-up data are needed to confirm the durability of these early results. The addition of IVL appears to increase the applicability of TCAR to highly calcified lesions and may offer expansion of indications for carotid stenting.

Highly accelerated time-of-flight magnetic resonance angiography using spiral imaging improves conspicuity of intracranial arterial branches while reducing scan time.

To systematically compare time-of-flight magnetic resonance angiography (TOF-MRA) acquired with Compressed SENSE (TOF-CS) to spiral imaging (TOF-Spiral) for imaging of brain-feeding arteries. Seventy-one patients (60.2 ± 19.5years, 43.7% females, 28.2% with pathology) who underwent TOF-MRA after implementation of a new scanner software program enabling spiral imaging were analyzed retrospectively. TOF-CS (standard sequence; duration ~ 4min) and the new TOF-Spiral (duration ~ 3min) were acquired. Image evaluation (vessel image quality and detectability, diagnostic confidence (1 (diagnosis very uncertain) to 5 (diagnosis very certain)), quantitative measurement of aneurysm diameter or degree of stenosis according to North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria) was performed by two readers. Quantitative assessments of pathology were compared to computed tomography angiography (CTA) or digital subtraction angiography (DSA). TOF-CS showed higher image quality for intraosseous and intradural segments of the internal carotid artery while TOF-Spiral better depicted small intracranial vessels like the anterior choroidal artery. All vessel pathologies were correctly identified by both readers for TOF-CS and TOF-Spiral with high confidence (TOF-CS (4.4 ± 0.6 and 4.3 ± 0.8), TOF-Spiral (4.3 ± 0.7 and 4.3 ± 0.8)) and good inter-reader agreement (Cohen's kappa > 0.8). Quantitative assessments of aneurysm size or stenosis did not significantly differ between TOF-CS or TOF-Spiral and CTA or DSA (p> 0.05). TOF-Spiral for imaging of brain-feeding arteries enables reductions in scan time without drawbacks in diagnostic confidence. A combination of spiral imaging and CS may help to overcome shortcomings of both sequences alone and could further reduce acquisition times in the future. • TOF-MRA with Compressed SENSE is superior in depicting arteries at the skull base while spiral TOF-MRA is able to better depict small intracranial vessels. • Both TOF-MRA with Compressed SENSE and TOF-MRA with spiral imaging provide high diagnostic confidence for detection of pathologies of brain-feeding arteries. • Spiral TOF-MRA is faster (by 25% for the sequence used in this study) than TOF-MRA with Compressed SENSE, thus enabling clear reductions in scan time for the clinical setting.

Platelet to lymphocyte ratio predicts all-cause mortality in patients with carotid arterial disease.

Platelet to lymphocyte ratio (PLR) has been demonstrated as a risk and prognostic marker in many of cardiovascular diseases. A relationship between PLR and severity of carotid stenosis has been shown. The aim of our study was to investigate the relationship between PLR and all cause mortality in patients with carotid arterial disease. This retrospective study included 146 patients who had been performed selective carotid angiography. Carotid stenosis were graded by the North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria. Platelet to lymphocyte ratio was calculated as the ratio of platelets to lymphocytes. The end point of the study was all-cause mortality. During median follow-up of 16 months (0-65 months) 15 (10.3%) patients suffered all-cause mortality. 50 patients (34.2%) underwent carotid endarterectomy and 69 patients (47.3%) had non-carotid cardiac surgery. 38 patients (26.02%) had cerebrovascular events (stroke/transient ischemic attack) at admission. NASCET grades were not different between survivors and non-survivors. Non-survivors had significantly lower hemoglobin (Hb) levels (12.7 ± 1.6 g/dL vs. 13.7 ± 1.7 g/dL, p = 0.031) and they were older than survivors (74.2 ± 8.4 years vs. 68.6 ± 8.5 years, p = 0.029). Non-survivors had significantly higher PLR values compared with survivors (190.3 ± 85.6 and 126.8 ± 53.8, p = 0.017). In multivariate analysis, only PLR predicted all-cause mortality in patients with carotid artery stenosis. In our study, higher PLR was associated with increased all-cause mortality.

Abstract WP163: From Static Imaging to Hemodynamic Modelling: Automated Nascet Grading Using Computational Fluid Dynamics

Aim: Duplex ultrasound is used for non-invasive assessment of internal carotid artery (ICA) disease and stenosis grading based on The North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria. Computational fluid dynamics (CFD) can be used to model blood flow based on static scans (like CT or MR angiograms), but such models are rarely validated in real clinical settings. We evaluated the accuracy of an automated vascular analysis software that simulates blood flow given a CT or MR angiogram (See-Mode Technologies, Singapore) against NASCET grading done by duplex ultrasound. Methods: 20 carotid arteries from patients with ICA disease were retrospectively analyzed using an automated vascular analysis software according to a blinded protocol. Three-dimensional models of the carotid arteries were reconstructed from MR or CT angiogram DICOM images, and CFD was used for patient-specific modelling of blood flow in the vasculature. Blood flow velocities, specifically ICA peak systolic velocity (PSV) and PSV ratio between the ICA and the common carotid artery (CCA) were obtained from the software and used for stenosis grading based on the NASCET criteria. Bland-Altman analysis was used to assess the agreement between the software and duplex ultrasound. Results: The blood flow simulations were in excellent agreement with duplex ultrasound for both metrics, i.e. ICA PSV (r 2 = 0.936, P &lt; 0.001) and ICA/CCA PSV ratio (r 2 = 0.932, P &lt; 0.001). There was no significant over or under estimation of ICA PSV, but there was a slight over estimation of the ICA/CCA PSV ratio with the software (ICA PSV: bias = 5 cm/s, lower limit of agreement (LOA) = -43 cm/s, upper LOA = 52 cm/s; ICA/CCA PSV ratio: bias = 0.16, lower LOA = -0.54, upper LOA = 0.86). All carotid arteries were correctly classified with the software compared against the NASCET grading done with duplex ultrasound. Conclusion: While CFD is commonly used for modelling blood flow, its accuracy is rarely assessed in real clinical settings. This is the first validated comparison of carotid artery stenosis grading using blood flow simulations against duplex ultrasound. When the data was categorized according to NASCET criteria, all cases were correctly classified with the software compared against duplex ultrasound.

Are You Puzzled When Credentialing Entities Ask You for Criteria for External Carotid Artery Stenosis? A Study Correlating Peak Systolic Velocities and Degree of External Carotid Artery Stenosis Based on CT Angiography

External carotid artery (ECA) disease has been understated in the current literature, likely secondary to the lack of clinical neurological symptoms when this vessel is stenotic. However, vascular ultrasound credentialing entities request the adoption of specific criteria for the assessment of the ECA. Our purpose is to determine the ultrasound criteria for the detection of hemodynamically significant stenosis (50%-99%) using computed tomography angiography (CTA) as the reference standard. We included patients who had a carotid ultrasound and a CTA of the neck performed both within a 12-month period. Ultrasound measurements were reviewed for technical accuracy. CTAs were reassessed to determine the degree of stenosis of the bilateral ECAs adopting the North American Symptomatic Carotid Endarterectomy Trial criteria. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated for different peak systolic velocity (PSV) cutoff points to determine the most accurate PSV for detecting 50% to 99% stenosis of the ECA. Receiver operating curve analysis was used to assess diagnostic performance. Of the 536 ECAs included in this study, 13 were noted to be occluded by CTA. Six of these occlusions were accurately detected by ultrasound. There were 82 ECAs with 50% to 99% stenosis on CTA; these vessels had a significantly higher mean PSV compared to ECAs with &lt;50% stenosis (294 vs 122 cm/s) ( P &lt; .0001). A cutoff velocity of ⩾200 cm/s demonstrated a sensitivity, specificity, and overall accuracy of 0.84, 0.93, and 0.91, respectively. Using univariate analysis, smoking was significantly associated with the presence of ⩾50% ECA stenosis. We determined that a PSV cutoff of ⩾200 cm/s showed high sensitivity and specificity for detecting 50% to 99% ECA stenosis based on CTA.

The Use of the Agatston Calcium Score in Predicting Carotid Plaque Vulnerability

The use of the Agatston calcium scoring method has been described extensively in the coronary circulation, but to date, it has not been investigated in the extracranial carotid domain. We sought to evaluate this calcium scoring method in its ability to predict carotid plaque vulnerability. We retrospectively reviewed all computed tomography angiogram studies of the carotid arteries performed between March 2012 and March 2017 at a single institution. We identified 68 consecutive patients with 99 internal carotid arteries who met criteria for review. Total calcium was quantified by the Agatston scoring method using the OsiriX software. Stenosis severity was determined using North American Symptomatic Carotid Endarterectomy Trial criteria. The relation between Agatston score and degree of stenosis was evaluated using the Spearman's Rho coefficient (R). Of 99 internal carotid arteries, 71 were asymptomatic and 28 were symptomatic. Baseline characteristics were comparable, with no significant difference in patient characteristics. There were significant differences in mean Agatston scores for asymptomatic versus symptomatic arteries (121.95±70.27 vs. 34.83±47.77, P=0.0098, 50%-69% stenosis; 151.07±88.30 vs. 71.59±77.27, P=0.0006, 70%-99% stenosis). In both asymptomatic and symptomatic groups, Agatston calcium score increased as severity of stenosis increased. Higher Agatston score is protective against symptoms ipsilateral to the carotid lesion. Agatston calcium score may predict carotid plaque vulnerability, with higher scores associated with lower likelihood of developing symptoms ipsilateral to the carotid lesion. This score may be useful in predicting clinical behavior of carotid plaques.

Carotid endarterectomy in patients with recurrent symptoms associated with an ipsilateral carotid artery near occlusion with full collapse

ObjectiveNear occlusion (NO) of the internal carotid artery (ICA) with full collapse (NOFC) is a rare condition, with a prevalence of around 1%. Guidelines on carotid stenosis recommend a conservative treatment in patients with a single-event ipsilateral to a NOFC, but the optimal treatment for patients with recurrent symptoms associated with NOFC remains uncertain. We describe a consecutive series of patients with recurrent symptoms associated with NOFC (RSNOFC) who underwent carotid endarterectomy (CEA).MethodsFrom 2008 to 2017, 17 consecutive patients with RSNOFC were treated according to our standardized multidisciplinary work-up and protocol and included for this single-center cohort study. NO was defined according to the angiographic North American Symptomatic Carotid Endarterectomy Trial criteria. Only patients with NOFC were included in this study.ResultsStandard longitudinal CEA was performed in 15 patients, whereas in 2 patients the ICA was ligated with concomitant endarterectomy of the ECA. Within 30 postoperative days, one patient died from a hemorrhagic infarction. During follow-up (median 23 months) one patient died of unknown cause 90 days after CEA. No TIA, stroke, myocardial infarction or re-stenosis occurred in the remaining patients.ConclusionIn patients with RSNOFC, CEA may be considered a potential treatment option. Although procedural risks in this small subgroup may be higher as compared to patients with low-to-moderate risk anatomy, this risk may outbalance the natural course.

Dynamic change of carotid intraplaque hemorrhage volume in subjects with mild carotid stenosis

Background and PurposeEarly detection of intraplaque hemorrhage (IPH) in the carotid artery is important as it is correlated with an increased risk of cerebral ischemic events. We examined changes in IPH with magnetic resonance imaging (MRI) over an extended follow-up period in patients with mild carotid stenosis. Materials and MethodsFrom November 2013 to November 2015, we retrospectively reviewed cerebral MRI of 2036 patients, including magnetization-prepared rapid acquisition with gradient-echo (MPRAGE) sequences obtained with a 3.0 T (T) MRI unit. An experienced neuroradiologist reviewed all studies and found 38 patients with carotid IPH and carotid stenosis that were categorized as mild (<30%), according to the North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria. Twenty-five patients agreed to join this study and signed informed consent for (MPRAGE) sequence imaging. We used semi-automated software to measure IPH volume on both the initial and follow up scans. ResultsThe median follow-up time of patients with mild carotid stenosis and IPH was 33.3 months. IPH volume increased in 10 of 27 carotid arteries (37.0%), with a mean volume increase of 42.6 ± 44.0 mm3. IPH volume decreased in 17 of 27 carotid arteries (63%), with a mean volume decrease of 17.2 ± 22.8 mm3. Two patients without IPH at baseline showed IPH development on follow-up imaging. There were no significant differences in patient demographics between the two groups. ConclusionsCarotid IPH volume in subjects with mild carotid stenosis can change over time and may not be correlated with any typical patient demographics.

Automatic flow analysis of digital subtraction angiography using independent component analysis in patients with carotid stenosis.

PurposeCurrent time—density curve analysis of digital subtraction angiography (DSA) provides intravascular flow information but requires manual vasculature selection. We developed an angiographic marker that represents cerebral perfusion by using automatic independent component analysis.Materials and methodsWe retrospectively analyzed the data of 44 patients with unilateral carotid stenosis higher than 70% according to North American Symptomatic Carotid Endarterectomy Trial criteria. For all patients, magnetic resonance perfusion (MRP) was performed one day before DSA. Fixed contrast injection protocols and DSA acquisition parameters were used before stenting. The cerebral circulation time (CCT) was defined as the difference in the time to peak between the parietal vein and cavernous internal carotid artery in a lateral angiogram. Both anterior-posterior and lateral DSA views were processed using independent component analysis, and the capillary angiogram was extracted automatically. The full width at half maximum of the time—density curve in the capillary phase in the anterior-posterior and lateral DSA views was defined as the angiographic mean transient time (aMTT; i.e., aMTTAP and aMTTLat). The correlations between the degree of stenosis, CCT, aMTTAP and aMTTLat, and MRP parameters were evaluated.ResultsThe degree of stenosis showed no correlation with CCT, aMTTAP, aMTTLat, or any MRP parameter. CCT showed a strong correlation with aMTTAP (r = 0.67) and aMTTLat (r = 0.72). Among the MRP parameters, CCT showed only a moderate correlation with MTT (r = 0.67) and Tmax (r = 0.40). aMTTAP showed a moderate correlation with Tmax (r = 0.42) and a strong correlation with MTT (r = 0.77). aMTTLat also showed similar correlations with Tmax (r = 0.59) and MTT (r = 0.73).ConclusionApart from vascular anatomy, aMTT estimates brain parenchyma hemodynamics from DSA and is concordant with MRP. This process is completely automatic and provides immediate measurement of quantitative peritherapeutic brain parenchyma changes during stenting.

Carotid stenting for unilateral stenosis can increase contralateral hemispheric cerebral blood flow

BackgroundThe revascularization of carotid stenosis can increase ipsilateral cerebral blood flow (CBF). Occasionally, elevated CBF is also evident on the contralateral side, but this phenomenon is poorly understood.ObjectiveTo analyze retrospectively...

Hybrid Treatment of Extracranial Carotid Artery Disease.

High-degree stenosis of both innominate (IA) or left common carotid artery (CCA) and carotid bifurcation is uncommon but still represents a significant challenge to interventionists in many aspects including techniques, timing, and priority. There are several strategies for intervention that have been reported in the literature. A well-described, less-invasive strategy for extracranial tandem carotid lesions is concomitant carotid endarterectomy (CEA) with retrograde carotid angioplasty and stenting (CAS). In this study, we examine intermediate-term outcomes of this hybrid procedure and review other described treatments. Electronic medical records of all patients who underwent hybrid (ostial CAS and CEA) procedures in a tertiary center over the last 10 years were reviewed. High-degree stenosis of the IA or CCA was defined according to North American Symptomatic Carotid Endarterectomy Trial criteria. A total of 6 patients were identified. The population included 4 males and 2 females with a median age of 65 years. Five patients were symptomatic and all had stenosis >75% by angiography. Five of the patients underwent left CEA with proximal stenting and one patient underwent right-sided CEA with proximal stenting. Combined 30-day mortality and stroke rate was 0%. No restenosis, stroke, heart attack, or death occurred during a follow-up range of 1 to 36 months (mean 12.8 months, median 7.8 months). The combined CEA with retrograde stenting for tandem extracranial lesion procedure is safe and feasible, with adequate intermediate-term outcomes consistent with the recent literature.

Abstract TMP33: High Intensity Signal in the Plaque on 3DTOF MRA is Associated With Ischemic Stroke in the Patients With Low Grade Carotid Artery Stenosis

Background: Carotid artery stenosis is one of the major causes of ischemic strokes. However, degree of stenosis is not always correlated with frequency of ischemic strokes. Recently, it was reported that carotid intraplaque hemorrhage (IPH) was associated with accelerated plaque growth, luminal narrowing and development of symptomatic events. Maximum intensity projection (MIP) images are easily reformatted within from 5 minute, routine time-of-flight (TOF) sequences. The aim of this study was to evaluate the relationships between high intensity signal (HIS) in the carotid plaques on MIP images detected by routine three-dimensional TOF magnetic resonance angiography (3D-TOF MRA) and ischemic strokes. Materials and Methods: One hundred fifty two patients with low-grade carotid artery stenosis (North American Symptomatic Carotid Endarterectomy Trial criteria: 30% - 49%) were included. IPH was defined as the presence of HIS in the carotid plaques on MIP images of 3D-TOF MRA using the previously reported criteria. We analyzed the relationship between the presence of HIS in the plaques and prior ischemic strokes defined as ischemic lesions on diffusion weighed images of the brain. Results: HIS in the carotid plaque was present in 56 (37%) of 152 carotid arteries. Prior ipsilateral ischemic strokes were observed more frequently in HIS-positive group (12 of 56, 21.4%) than HIS-negative group (1 of 34: 2.9%) [p&lt;0.001]. In multivariate logistic regression analysis, HIS (Odds ratio: 77.7, 95%CI: 6.4 - 944.0, p&lt;0.001) and diabetes mellitus type 2 (odds ratio: 10.45, 95%CI: 1.6 - 67.9, p=0.014) were independent determinants of prior ischemic strokes after adjustment for age. Conclusions: HIS in the carotid plaques on MIP images of 3D-TOF MRA was an independent determinant of prior ischemic stroke in patients with low-grade carotid artery stenosis, and this finding may provide a reliable risk stratification of future stroke in patients with low-grade carotid artery stenosis.

High-Intensity Signal in Carotid Plaque on Routine 3D-TOF-MRA Is a Risk Factor of Ischemic Stroke

Background: Carotid atherosclerotic disease is recognized as an important risk factor for brain ischemic events. However, high-grade stenosis does not always cause ischemic strokes, whereas moderate-grade stenosis may often cause ischemic strokes. It has been reported that there is an association between carotid intraplaque hemorrhage (IPH) and new cerebral ischemic events. The purpose of this study was to elucidate the relationship between high-intensity signals (HIS) on maximum intensity projection (MIP) images from routine 3-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) and prior ischemic strokes in the patients with moderate carotid stenosis. Materials and Methods: Sixty-one patients with moderate carotid artery stenosis (50-69% stenosis based on North American Symptomatic Carotid Endarterectomy Trial criteria) were included. Carotid IPH was defined as the presence of HIS in carotid plaques on MIP images detected by 3D-TOF-MRA using criteria we previously reported. We analyzed the relationship between the presence of HIS in plaques and prior ischemic strokes defined as ischemic lesions on diffusion-weighted brain images. Results: HIS in carotid plaques were present in 27 (44%) of 61 patients. Prior ipsilateral ischemic strokes occurred more frequently in the HIS-positive group than the HIS-negative group (67 vs. 9%, p < 0.001). Furthermore, there were more smokers in the group with ischemic stroke than without it (62 vs. 25%, p = 0.005). In multivariate logistic regression analysis, HIS in carotid plaque (OR 23.4, 95% CI 4.62-118.3, p < 0.001) and smoking (OR 5.44, 95% CI 1.20-24.6, p = 0.028) were independent determinants of prior ischemic strokes after adjustment for age. Conclusions: HIS in carotid plaques on 3D-TOF-MRA MIP images are independent determinants of prior ischemic strokes in patients with moderate carotid artery stenosis, and they can potentially provide a reliable risk stratification of patients with moderate carotid artery stenosis.