Vessel wall magnetic resonance and arterial spin labelling imaging in the management of presumed inflammatory intracranial arterial vasculopathy.

Optimal criteria for diagnosing and monitoring response to treatment for infectious and inflammatory medium-large vessel intracranial vasculitis presenting with stroke are lacking. We integrated intracranial vessel wall MRI with arterial spin labelling into our routine clinical stroke pathway to detect presumed inflammatory intracranial arterial vasculopathy, and monitor disease activity, in patients with clinical stroke syndromes. We used predefined standardized radiological criteria to define vessel wall enhancement, and all imaging findings were rated blinded to clinical details. Between 2017 and 2018, stroke or transient ischaemic attack patients were first screened in our vascular radiology meeting and followed up in a dedicated specialist stroke clinic if a diagnosis of medium-large inflammatory intracranial arterial vasculopathy was radiologically confirmed. Treatment was determined and monitored by a multi-disciplinary team. In this case series, 11 patients were managed in this period from the cohort of young stroke presenters (<55 years). The median age was 36 years (interquartile range: 33,50), of which 8 of 11 (73%) were female. Two of 11 (18%) had herpes virus infection confirmed by viral nucleic acid in the cerebrospinal fluid. We showed improvement in cerebral perfusion at 1 year using an arterial spin labelling sequence in patients taking immunosuppressive therapy for >4 weeks compared with those not receiving therapy [6 (100%) versus 2 (40%) P = 0.026]. Our findings demonstrate the potential utility of vessel wall magnetic resonance with arterial spin labelling imaging in detecting and monitoring medium-large inflammatory intracranial arterial vasculopathy activity for patients presenting with stroke symptoms, limiting the need to progress to brain biopsy. Further systematic studies in unselected populations of stroke patients are needed to confirm our findings and establish the prevalence of medium-large artery wall inflammation.

Roadmap Consensus on Carotid Artery Plaque Imaging and Impact on Therapy Strategies and Guidelines: An International, Multispecialty, Expert Review and Position Statement.

Current guidelines for primary and secondary prevention of stroke in patients with carotid atherosclerosis are based on the quantification of the degree of stenosis and symptom status. Recent publications have demonstrated that plaque morphology and composition, independent of the degree of stenosis, are important in the risk stratification of carotid atherosclerotic disease. This finding raises the question as to whether current guidelines are adequate or if they should be updated with new evidence, including imaging for plaque phenotyping, risk stratification, and clinical decision-making in addition to the degree of stenosis. To further this discussion, this roadmap consensus article defines the limits of luminal imaging and highlights the current evidence supporting the role of plaque imaging. Furthermore, we identify gaps in current knowledge and suggest steps to generate high-quality evidence, to add relevant information to guidelines currently based on the quantification of stenosis.

Timing of procedural stroke and death in asymptomatic patients undergoing carotid endarterectomy: individual patient analysis from four RCTs.

BACKGROUND: The effectiveness of carotid endarterectomy (CEA) for stroke prevention depends on low procedural risks. The aim of this study was to assess the frequency and timing of procedural complications after CEA, which may clarify underlying mechanisms and help inform safe discharge policies. METHODS: Individual-patient data were obtained from four large carotid intervention trials (VACS, ACAS, ACST-1 and GALA; 1983-2007). Patients undergoing CEA for asymptomatic carotid artery stenosis directly after randomization were used for the present analysis. Timing of procedural death and stroke was divided into intraoperative day 0, postoperative day 0, days 1-3 and days 4-30. RESULTS: Some 3694 patients were included in the analysis. A total of 103 patients (2·8 per cent) had serious procedural complications (18 fatal strokes, 68 non-fatal strokes, 11 fatal myocardial infarctions and 6 deaths from other causes) [Correction added on 20 April, after first online publication: the percentage value has been corrected to 2·8]. Of the 86 strokes, 67 (78 per cent) were ipsilateral, 17 (20 per cent) were contralateral and two (2 per cent) were vertebrobasilar. Forty-five strokes (52 per cent) were ischaemic, nine (10 per cent) haemorrhagic, and stroke subtype was not determined in 32 patients (37 per cent). Half of the strokes happened on the day of CEA. Of all serious complications recorded, 44 (42·7 per cent) occurred on day 0 (20 intraoperative, 17 postoperative, 7 with unclear timing), 23 (22·3 per cent) on days 1-3 and 36 (35·0 per cent) on days 4-30. CONCLUSION: At least half of the procedural strokes in this study were ischaemic and ipsilateral to the treated artery. Half of all procedural complications occurred on the day of surgery, but one-third after day 3 when many patients had been discharged.

ANTECEDENTES: La efectividad de la endarterectomía carotídea (carotid endarterectomy, CEA) en la prevención de un accidente cerebrovascular depende de que este procedimiento tenga pocos riesgos. El objetivo de este estudio fue evaluar la frecuencia y el momento de aparición de las complicaciones tras una CEA, lo que podría clarificar los mecanismos subyacentes y ayudar a establecer una política de altas hospitalarias segura. MÉTODOS: Se utilizaron los datos de los pacientes incluidos en cuatro grandes ensayos de intervención carotídea (VACS, ACAS, ACST-1 y GALA; 1983-2007). Para el presente análisis se utilizaron los datos de pacientes sometidos a CEA por estenosis de la arteria carótida asintomática recogidos inmediatamente tras la aleatorización. Se consideraron diferentes intervalos entre el procedimiento, la muerte o el accidente cerebrovascular: intraoperatorio día 0, postoperatorio día 0, postoperatorio días 1-3 y postoperatorio días 4-30. RESULTADOS: En el análisis se incluyeron 3.694 pacientes. Se detectaron complicaciones graves relacionadas con el procedimiento en 103 (2,8%) pacientes (18 accidentes cerebrovasculares fatales, 68 accidentes cerebrovasculares no fatales, 11 infartos de miocardio fatales y 6 muertes por otras causas). De los 86 accidentes cerebrovasculares, 67 (78%) fueron ipsilaterales, 17 (20%) contralaterales y dos (2%) vertebrobasilares. Los accidentes cerebrovasculares fueron isquémicos en 45 (52%) casos, hemorrágicos en 9 (10%) y no se pudo determinar el subtipo de ictus en 32 (37%). La mitad de los accidentes cerebrovasculares ocurrieron el día de la CEA. De todas las complicaciones graves registradas, 44 (43%) ocurrieron en el día 0 (20 intraoperatorias, 17 postoperatorias y 7 en períodos poco definidos), 23 (22%) entre los días 1-3 y 36 (35%) entre los días 4-30. CONCLUSIÓN: En este estudio, al menos la mitad de los accidentes cerebrovasculares relacionados con la CEA fueron isquémicos e ipsilaterales respecto a la arteria tratada. La mitad de todas las complicaciones de la CEA ocurrieron el día de la cirugía, pero un tercio de los casos se presentaron después del día 3, cuando muchos pacientes ya habían sido dados de alta.

Baseline factors associated with early and late death in intracerebral haemorrhage survivors.

BACKGROUND AND PURPOSE: The aim of this study was to determine whether early and late death are associated with different baseline factors in intracerebral haemorrhage (ICH) survivors. METHODS: This was a secondary analysis of the multicentre prospective observational CROMIS-2 ICH study. Death was defined as 'early' if occurring within 6 months of study entry and 'late' if occurring after this time point. RESULTS: In our cohort (n = 1094), there were 306 deaths (per 100 patient-years: absolute event rate, 11.7; 95% confidence intervals, 10.5-13.1); 156 were 'early' and 150 'late'. In multivariable analyses, early death was independently associated with age [per year increase; hazard ratio (HR), 1.05, P = 0.003], history of hypertension (HR, 1.89, P = 0.038), pre-event modified Rankin scale score (per point increase; HR, 1.41, P < 0.0001), admission National Institutes of Health Stroke Scale score (per point increase; HR, 1.11, P < 0.0001) and haemorrhage volume >60 mL (HR, 4.08, P < 0.0001). Late death showed independent associations with age (per year increase; HR, 1.04, P = 0.003), pre-event modified Rankin scale score (per point increase; HR, 1.42, P = 0.001), prior anticoagulant use (HR, 2.13, P = 0.028) and the presence of intraventricular extension (HR, 1.73, P = 0.033) in multivariable analyses. In further analyses where time was treated as continuous (rather than dichotomized), the HR of previous cerebral ischaemic events increased with time, whereas HRs for Glasgow Coma Scale score, National Institutes of Health Stroke Scale score and ICH volume decreased over time. CONCLUSIONS: We provide new evidence that not all baseline factors associated with early mortality after ICH are associated with mortality after 6 months and that the effects of baseline variables change over time. Our findings could help design better prognostic scores for later death after ICH.

Contemporary prevalence of carotid stenosis in patients presenting with ischaemic stroke.

BACKGROUND: Carotid stenosis is a common cause of ischaemic stroke and transient ischaemic attack (TIA). Despite rising recognition and centralization of stroke services there has been a decline in interventions for carotid stenosis in recent years. The aim of this study was to determine the current prevalence and management of carotid stenosis in the UK. METHODS: This was a 1-year prospective observational study of consecutive patients presenting with ischaemic stroke, TIA or ischaemic retinal artery occlusion to a central London hyperacute stroke unit. Patients with significant carotid stenosis, defined as atherosclerotic narrowing of 50 per cent or greater, underwent multidisciplinary team (MDT) discussion to determine the cause of stroke/TIA and classify carotid stenosis as symptomatic or incidental. RESULTS: In total, 2707 patients were seen; half had an ischaemic event and the majority had carotid imaging (1252 of 1444). Carotid stenosis of at least 50 per cent was seen in 238 (prevalence 19·0 (95 per cent c.i. 16·6 to 21·4) per cent). Patients with significant carotid stenosis were more likely to have hypertension, hypercholesterolaemia, diabetes and ischaemic heart disease. Carotid stenosis was deemed symptomatic in 99 patients (7·9 (6·3 to 9·5) per cent); of these, 17 had carotid occlusion, 17 were unfit for surgery and 58 patients were referred for carotid intervention. Among 139 patients with asymptomatic stenosis, 75 had carotid stenosis ipsilateral to the stroke but, after MDT discussion, the cause was deemed to be atrial fibrillation (32), small-vessel disease (15), another determined cause (5), or not determined owing to atypical imaging or clinical presentation. CONCLUSION: Carotid stenosis is common, affecting one in five patients presenting with stroke or TIA. Careful MDT discussion may avoid unnecessary intervention and should be the standard of care.

Don't be the "Fifth Guy": Risk, Responsibility, and the Rhetoric of Handwashing Campaigns.

In recent years, outbreaks such as H1N1 have prompted heightened efforts to manage the risk of infection. These efforts often involve the endorsement of personal responsibility for infection risk, thus reinforcing an individualistic model of public health. Some scholars-for example, Peterson and Lupton (1996)-term this model the "new public health." In this essay, I describe how the focus on personal responsibility for infection risk shapes the promotion of hand hygiene and other forms of illness etiquette. My analysis underscores the use of constitutive and stigmatizing rhetoric to depict individual bodies, rather than environments, as prime sources of infection. Common among workplaces, this rhetoric provides the impetus for encouraging individual behavior change as a hedge against infection risk. I argue, though, that the mandating of personal responsibility for infection risk galvanizes a culture of stigma and blame that may work against the aims of public health.

Upper Extremity Blood Pressure Difference in Patients Undergoing Carotid Revascularisation.

INTRODUCTION: Blood pressure (BP) regulation is important in patients with carotid artery atherosclerotic disease. Concomitant subclavian artery stenosis (SAS) might lead to an underestimation of the true systemic BP in the monitoring of these patients. This study aimed to assess the prevalence of the inter-arm BP difference in patients undergoing carotid intervention and its association with ipsilateral significant subclavian stenosis and clinical outcome. METHODS: Bilateral BP measurements and vascular imaging (CTA and MRA) of both subclavian arteries and the innominate artery were assessed in 182 symptomatic patients with carotid artery stenosis undergoing revascularisation in the International Carotid Stenting Study (ICSS). Data were separately analysed according to previously described cutoff values for systolic BP (SBP) differences of ≥10 and <15 mmHg, ≥15 and <20 mmHg, or ≥20 mmHg. Significant SAS was defined as a >50% diameter reduction. RESULTS: Of the 182 patients, 39 (21%) showed an inter-arm difference in SBP >15 mmHg. The mean inter-arm SBP difference associated with ipsilateral SAS was 14 mmHg. SAS was present in 21/182 (12%) patients. Only two patients (1%) had bilateral stenotic disease. An inter-arm SBP difference of ≥20 mmHg was associated with unilateral SAS (RR 11.8; 95% CI 3.2-43.1) with a sensitivity of 23% and a specificity of 98%. Patients were followed up for a median of 4.0 years (IQR 3.0-6.0; maximum 7.5). Risk of stroke or death during follow-up was 20.0% (95% CI 11.1-28.9) in patients with, and 15.1% (95% CI 12.3-17.9) in patients without SAS (p = .561). The hospital stay was longer in patients with significant SAS (5.0 days, SD 4.9 vs. 2.7 days, SD 4.3, p = .035). CONCLUSION: The present study is the first to affirm the clinical need for the measurement of inter-arm BP differences in patients undergoing carotid revascularisation, especially in the post-operative phase in the prevention of cerebral hyperperfusion.

Predictors of Stroke, Myocardial Infarction or Death within 30 Days of Carotid Artery Stenting: Results from the International Carotid Stenting Study.

OBJECTIVES: Stroke, myocardial infarction (MI), and death are complications of carotid artery stenting (CAS). The effect of baseline patient demographic factors, processes of care, and technical factors during CAS on the risk of stroke, MI, or death within 30 days of CAS in the International Carotid Stenting Study (ICSS) were investigated. METHODS: In ICSS, suitable patients with recently symptomatic carotid stenosis > 50% were randomly allocated to CAS or endarterectomy. Factors influencing the risk of stroke, MI, or death within 30 days of CAS were examined in a regression model for the 828 patients randomized to CAS in whom the procedure was initiated. RESULTS: Of the patients, 7.4% suffered stroke, MI, or death within 30 days of CAS. Independent predictors of risk were age (risk ratio [RR] 1.17 per 5 years of age, 95% CI 1.01-1.37), a right-sided procedure (RR 0.54, 95% CI 0.32-0.91), aspirin and clopidogrel in combination prior to CAS (compared with any other antiplatelet regimen, RR 0.59, 95% CI 0.36-0.98), smoking status, and the severity of index event. In patients in whom a stent was deployed, use of an open-cell stent conferred higher risk than use of a closed-cell stent (RR 1.92, 95% CI 1.11-3.33). Cerebral protection device (CPD) use did not modify the risk. CONCLUSIONS: Selection of patients for CAS should take into account symptoms, age, and side of the procedure. The results favour the use of closed-cell stents. CPDs in ICSS did not protect against stroke.

Carotid Anatomy Does Not Predict the Risk of New Ischaemic Brain Lesions on Diffusion-Weighted Imaging after Carotid Artery Stenting in the ICSS-MRI Substudy.

INTRODUCTION: The International Carotid Stenting Study (ICSS, ISRCTN25337470) randomized patients with recently symptomatic carotid artery stenosis > 50% to carotid artery stenting (CAS) or endarterectomy. CAS increased the risk of new brain lesions visible on diffusion-weighted magnetic resonance imaging (DWI-MRI) more than endarterectomy in the ICSS-MRI Substudy. The predictors of new post-stenting DWI lesions were assessed in these patients. METHODS: ICSS-MRI Substudy patients allocated to CAS were studied. Baseline or pre-stenting catheter angiograms were rated to determine carotid anatomy. Baseline patient demographics and the influence of plaque length, plaque morphology, internal carotid angulation, and external or common carotid atheroma were examined in negative binomial regression models. RESULTS: A total of 115 patients (70% male, average age 70.4) were included; 50.4% had at least one new DWI-MRI-positive lesion following CAS. Independent risk factors increasing the number of new lesions were a left-sided stenosis (incidence risk ratio [IRR] 1.59, 95% CI 1.04-2.44, p = .03), age (IRR 2.10 per 10-year increase in age, 95% CI 1.61-2.74, p < .01), male sex (IRR 2.83, 95% CI 1.72-4.67, p < .01), hypertension (IRR 2.04, 95% CI 1.25-3.33, p < .01) and absence of cardiac failure (IRR 6.58, 95% CI 1.23-35.07, p = .03). None of the carotid anatomical features significantly influenced the number of post-procedure lesions. CONCLUSION: Carotid anatomy seen on pre-stenting catheter angiography did not predict of the number of ischaemic brain lesions following CAS.

Risk Factors For Stroke, Myocardial Infarction, or Death Following Carotid Endarterectomy: Results From the International Carotid Stenting Study.

OBJECTIVES: Carotid endarterectomy (CEA) is standard treatment for symptomatic carotid artery stenosis but carries a risk of stroke, myocardial infarction (MI), or death. This study investigated risk factors for these procedural complications occurring within 30 days of endarterectomy in the International Carotid Stenting Study (ICSS). METHODS: Patients with recently symptomatic carotid stenosis >50% were randomly allocated to endarterectomy or stenting. Analysis is reported of patients in ICSS assigned to endarterectomy and limited to those in whom CEA was initiated. The occurrence of stroke, MI, or death within 30 days of the procedure was reported by investigators and adjudicated. Demographic and technical risk factors for these complications were analysed sequentially in a binomial regression analysis and subsequently in a multivariable model. RESULTS: Eight-hundred and twenty-one patients were included in the analysis. The risk of stroke, MI, or death within 30 days of CEA was 4.0%. The risk was higher in female patients (risk ratio [RR] 1.98, 95% CI 1.02-3.87, p = .05) and with increasing baseline diastolic blood pressure (dBP) (RR 1.30 per +10 mmHg, 95% CI 1.02-1.66, p = .04). Mean baseline dBP, obtained at the time of randomization in the trial, was 78 mmHg (SD 13 mmHg). In a multivariable model, only dBP remained a significant predictor. The risk was not related to the type of surgical reconstruction, anaesthetic technique, or perioperative medication regimen. Patients undergoing CEA stayed a median of 4 days before discharge, and 21.2% of events occurred on or after the day of discharge. CONCLUSIONS: Increasing diastolic blood pressure was the only independent risk factor for stroke, MI, or death following CEA. Cautious attention to blood pressure control following symptoms attributable to carotid stenosis could reduce the risks associated with subsequent CEA.

Mechanism of Procedural Stroke Following Carotid Endarterectomy or Carotid Artery Stenting Within the International Carotid Stenting Study (ICSS) Randomised Trial.

OBJECTIVE: To decrease the procedural risk of carotid revascularisation it is crucial to understand the mechanisms of procedural stroke. This study analysed the features of procedural strokes associated with carotid artery stenting (CAS) and carotid endarterectomy (CEA) within the International Carotid Stenting Study (ICSS) to identify the underlying pathophysiological mechanism. MATERIALS AND METHODS: Patients with recently symptomatic carotid stenosis (1,713) were randomly allocated to CAS or CEA. Procedural strokes were classified by type (ischaemic or haemorrhagic), time of onset (intraprocedural or after the procedure), side (ipsilateral or contralateral), severity (disabling or non-disabling), and patency of the treated artery. Only patients in whom the allocated treatment was initiated were included. The most likely pathophysiological mechanism was determined using the following classification system: (1) carotid-embolic, (2) haemodynamic, (3) thrombosis or occlusion of the revascularised carotid artery, (4) hyperperfusion, (5) cardio-embolic, (6) multiple, and (7) undetermined. RESULTS: Procedural stroke occurred within 30 days of revascularisation in 85 patients (CAS 58 out of 791 and CEA 27 out of 819). Strokes were predominately ischaemic (77; 56 CAS and 21 CEA), after the procedure (57; 37 CAS and 20 CEA), ipsilateral to the treated artery (77; 52 CAS and 25 CEA), and non-disabling (47; 36 CAS and 11 CEA). Mechanisms of stroke were carotid-embolic (14; 10 CAS and 4 CEA), haemodynamic (20; 15 CAS and 5 CEA), thrombosis or occlusion of the carotid artery (15; 11 CAS and 4 CEA), hyperperfusion (9; 3 CAS and 6 CEA), cardio-embolic (5; 2 CAS and 3 CEA) and multiple causes (3; 3 CAS). In 19 patients (14 CAS and 5 CEA) the cause of stroke remained undetermined. CONCLUSION: Although the mechanism of procedural stroke in both CAS and CEA is diverse, haemodynamic disturbance is an important mechanism. Careful attention to blood pressure control could lower the incidence of procedural stroke.

Carotid artery: overview on current trials--selecting the low-risk patient.

The ultimate goal of carotid stenosis treatment is the long-term prevention of stroke. While a large number of studies focusing on patients with symptomatic carotid stenosis have been carried out, fewer data are available from trials on asymptomatic and low-risk patients. Currently existing information on the optimal management of these patients is inconclusive and contradictory. Our aim was to review previous major trials conducted on carotid disease with a main focus on asymptomatic patients with carotid stenosis. Efforts to present currently ongoing trials involving asymptomatic carotid patients, to survey recent studies determining patients' risk for future stroke or periprocedural events, as well as to summarize data on promising structural and functional variables and biomarkers predicting future stroke risk have been made.

Incidence, impact, and predictors of cranial nerve palsy and haematoma following carotid endarterectomy in the international carotid stenting study.

OBJECTIVE: Cranial nerve palsy (CNP) and neck haematoma are complications of carotid endarterectomy (CEA). The effects of patient factors and surgical technique were analysed on the risk, and impact on disability, of CNP or haematoma in the surgical arm of the International Carotid Stenting Study (ICSS), a randomized controlled clinical trial of stenting versus CEA in patients with symptomatic carotid stenosis. MATERIALS AND METHODS: A per-protocol analysis of early outcome in patients receiving CEA in ICSS is reported. Haematoma was defined by the surgeon. CNP was confirmed by an independent neurologist. Factors associated with the risk of CNP and haematoma were investigated in a binomial regression analysis. RESULTS: Of the patients undergoing CEA, 45/821 (5.5%) developed CNP, one of which was disabling (modified Rankin score = 3 at 1 month). Twenty-eight (3.4%) developed severe haematoma. Twelve patients with haematoma also had CNP, a significant association (p < .01). Independent risk factors modifying the risk of CNP were cardiac failure (risk ratio [RR] 2.66, 95% CI 1.11 to 6.40), female sex (RR 1.80, 95% CI 1.02 to 3.20), the degree of contralateral carotid stenosis, and time from randomization to treatment >14 days (RR 3.33, 95% CI 1.05 to 10.57). The risk of haematoma was increased in women, by the prescription of anticoagulant drugs pre-procedure and in patients with atrial fibrillation, and was decreased in patients in whom a shunt was used and in those with a higher baseline cholesterol level. CONCLUSIONS: CNP remains relatively common after CEA, but is rarely disabling. Women should be warned about an increased risk. Attention to haemostasis might reduce the incidence of CNP. ICSS is a registered clinical trial: ISRCTN 25337470.

Echographic risk index and cerebral ischemic brain lesions in patients randomized to stenting versus endarterectomy for symptomatic carotid artery stenosis.

PURPOSE: It remains to be determined whether the impact of plaque characteristics on procedural risks differs between carotid artery stenting (CAS) and endarterectomy (CEA). We studied whether quantitative assessment of carotid plaque echolucency on ultrasound predicts the risk of embolism during CAS or CEA. MATERIALS AND METHODS: In 50 consecutive patients with symptomatic carotid stenosis randomized to CAS (n = 26) or CEA (n = 24) in the International Carotid Stenting Study (ICSS), semi-automated grayscale measurement of carotid plaques on baseline ultrasound was performed. We determined the grayscale median (GSM), percentage of echolucent plaque area, and a previously defined echographic risk index (ERI) calculated with the echolucent area and degree of stenosis. Brain MRI including diffusion-weighted imaging (DWI) was performed within 7 days before and 3 days after treatment. The primary outcome was the presence of at least 1 new hyperintense DWI lesion (DWI+) after treatment. RESULTS: In the CAS group, DWI+ patients (n = 18) had a significantly higher ERI at baseline (mean 0.11 ±â€Š0.12) than patients without new lesions (n = 8; mean 0.03 ±â€Š0.01; p = 0.012). GSM (mean 26.7 ±â€Š18.7 versus 34.3 ±â€Š8.0, p = 0.16) and echolucent plaque area (mean 42.8 ±â€Š21.1 versus 31.2 ±â€Š8.2, p = 0.054) did not differ significantly. In the CEA group, there were no differences in plaque echogenity measurements between patients with (n = 2) and without DWI lesions (n = 22). CONCLUSION: Patients with echolucent plaques causing severe narrowing are at increased risk for cerebral embolism during CAS. Quantitative ultrasound plaque analysis, with ERI in particular, may add to clinical variables in identifying patients at risk for procedural stroke with CAS, but larger studies with clinical endpoints are needed.

Carotid stenting: is there an operator effect? A pooled analysis from the carotid stenting trialists' collaboration.

BACKGROUND AND PURPOSE: Randomized clinical trials show higher 30-day risk of stroke or death after carotid artery stenting compared with surgery. We examined whether operator experience is associated with 30-day risk of stroke or death in the Carotid Stenting Trialists' Collaboration database. METHODS: The Carotid Stenting Trialists' Collaboration is a pooled individual patient database including all patients recruited in 3 randomized trials of stenting versus endarterectomy for symptomatic carotid stenosis (Endarterectomy Versus Angioplasty in patients with Symptomatic Severe Carotid Stenosis trial, Stent-Protected Angioplasty versus Carotid Endarterectomy trial, and International Carotid Stenting Study). Lifetime carotid artery stenting experience, lifetime experience in stenting procedures excluding the carotid, and annual number of procedures performed within the trial (in-trial volume), divided into tertiles, were used to measure operator experience. The outcome event was the occurrence of any stroke or death within 30 days of the procedure. The analysis was done per protocol. RESULTS: Among 1546 patients who underwent carotid artery stenting, 120 (7.8%) had a stroke or death within 30 days of the procedure. The 30-day risk of stroke or death did not differ according to operator lifetime carotid artery stenting experience (P=0.8) or operator lifetime stenting experience excluding the carotid (P=0.7). In contrast, the 30-day risk of stroke or death was significantly higher in patients treated by operators with low (mean ≤3.2 procedures/y; risk 10.1%; adjusted risk ratio=2.30 [1.36-3.87]) and intermediate annual in-trial volumes (3.2-5.6 procedures/y; 8.4%; adjusted risk ratio=1.93 [1.14-3.27]) compared with patients treated by high annual in-trial volume operators (>5.6 procedures/y; 5.1%). CONCLUSIONS: Carotid stenting should only be performed by operators with annual procedure volume ≥6 cases per year.

Flow velocities in the external carotid artery following carotid revascularization.

OBJECTIVE: To study the changes in peak systolic velocities of the ipsilateral external carotid artery (ECA) following carotid revascularization. METHODS: All patients randomized to carotid artery stenting (CAS) or carotid endarterectomy (CEA) in the International Carotid Stenting Study (ICSS; ISRCTN25337470) in our center were included. Peak systolic velocities (PSV) were assessed with duplex ultrasound (DUS) at baseline, at 30 days, and at 12 and 24 months after treatment. Our primary outcome measure was the change in blood flow velocities in the ECA (ΔPSVECA). Secondary outcome measure was the prevalence of post interventional ECA occlusion. RESULTS: Of 270 patients enrolled in ICSS at our center, 224 patients (mean age, 68.8 years; 154 males) were included in the present study (116 CAS, 108 CEA). Baseline PSV in the ipsilateral ECA was similar between the groups. Following CAS, PSV gradually increased during follow-up, whereas PSV remained relatively stable after CEA; mean difference of PSV between CAS and CEA: 23 cm/s (95% CI, -5 to 52), 58 cm/s (95% CI, 27-89), and 69 cm/s (95% CI, 31-107) at 30 days, 12 months, and 24 months. One new ECA occlusion occurred after CAS and two after CEA. CONCLUSION: Blood flow velocities in the ipsilateral ECA increase significantly after CAS but not after CEA. However, this does not lead to a higher rate of ECA occlusion in the first 2 years after revascularization. We conclude that CAS is not inferior to CEA in preserving the ECA as a possible potential collateral pathway for cerebral blood supply within 2 years following revascularization.

Interprocedural comparison of changes in natural flow velocity patterns in the internal carotid artery following CAS or CEA.

BACKGROUND AND PURPOSE: Different flow velocities have been reported after carotid angioplasty with stenting (CAS) than after carotid endarterectomy (CEA). We compared blood flow velocities following CAS and CEA in the International Carotid Stenting Study (ICSS; ISRCTN25337470). MATERIALS AND METHODS: In total, 254 patients (70% male; 129 CAS and 125 CEA) were included. Mean peak systolic velocities (PSVICA) were assessed at baseline, 30 days, 1 and 2 years. Following both treatments, restenosis ≥ 50% was defined as PSVmean >125 cm s(-1). RESULTS: CAS and CEA resulted in a similar reduction in PSVICA 1 month after treatment. Post-intervention analysis for each treatment separately revealed that PSVICA following CAS increased significantly during follow-up (30 days to 2 years; 22.4 cm s(-1); 95% confidence interval (CI), 14.3 to 30.5). On the contrary, PSVICA following CEA remained relatively stable during follow-up (4.7 cm s(-1); 95% CI, -6.5 to 15.9). When we analysed the increase in PSVICA between both treatments after 2 years of follow-up, no significant interprocedural difference was observed. The internal carotid artery/common carotid artery (ICA/CCA) PSV ratio increased after CAS but not after CEA: 1.2 vs. 1.1 (0.04, 95% CI; -0.16 to 0.25) at 30 days; 1.5 vs. 1.1 (0.39, 95% CI; 0.13 to 0.65) at 1 year; and 1.5 vs. 1.1 (0.36; 95% CI, 0.08 to 0.63) at 2 years. The rate of apparent ipsilateral ICA restenosis >50% was higher following CAS (hazard ratio 2.35; 95% CI, 1.35 to 4.09). CONCLUSION: Two years after carotid revascularisation, no significant interprocedural difference was observed in the increase of PSVICA between CAS and CEA. However, the ICA/CCA ratio increased more following CAS resulting in an apparent higher rate of restenosis following CAS.

Vascular crossing patterns in patients with systemic arterial hypertension.

AIM: To identify the relationship of retinal arteries in a population with systemic arterial hypertension. METHODS: High resolution, dilated, digitised, fundus photographs of consecutive patients with a history of hypertension requiring pharmacologic therapy seen on the Wills Eye Hospital Retina Service were analysed. Included were photographs of the temporal retinal vascular arcades in which media clarity permitted good visualisation of third-order retinal vascular bifurcations. Each first- and second-order arteriovenous (AV) crossing was then examined to identify anatomic patterns at the sites where veins and arteries crossed. Eyes in patients without a history of hypertension were used as controls. RESULTS: Among the 71 patients (134 eyes), there were 430 first-order and second-order AV crossings, in which AV nicking was present at 126 sites. A retinal artery was located anterior to the retinal vein in 122 of the 126 sites (96.8%) at which AV nicking was noted, while nicking associated with the vein located anteriorly to the artery occurred in only 4 of 126 (3.2%) of AV crossings (p<0.001). An anatomical pattern of venous arching, or cascading of a retinal vein over a retinal artery, was noted predominantly when the vein was positioned anterior to the artery in both subjects and controls. Among the 43 venous arching sites in the study group, 41 (95.3%) demonstrated the retinal vein anterior to retinal artery (p<0.001). CONCLUSIONS: In patients with systemic arterial hypertension and hypertensive retinopathy, AV nicking of the retinal vein at the site of AV crossing is seen predominantly when the retinal artery lies anterior to the vein, but generally not when the vein lies anterior to the artery. The clinician should realise that when a retinal vein lies anterior to a retinal artery, the absence of AV nicking does not rule out more severe, chronic, retinopathic changes than observed with retinal arterial straightening only.

Cerebral microbleeds and long-term cognitive outcome: longitudinal cohort study of stroke clinic patients.

BACKGROUND: Vascular cognitive impairment causes significant disability in the elderly and is common following ischaemic stroke. Although the underlying mechanisms and prognostic factors remain unclear, small vessel diseases are known to contribute. Cerebral microbleeds (CMBs) are a magnetic resonance imaging (MRI) manifestation of small vessel diseases and may contribute to vascular cognitive impairment, particularly frontal-executive functions. We hypothesized that baseline CMBs would predict long-term cognitive outcome, specifically frontal-executive function. METHODS: A cohort of consecutive patients found to have CMBs when first referred to a stroke clinic, together with a CMB-free control group matched for age, gender and clinicoradiological characteristics, were invited for follow-up cognitive assessment a median of 5.7 years later. MRI and detailed cognitive assessment (including current intellectual function, verbal memory, visual memory, naming skills, perceptual functions, frontal-executive functions; and speed and attention) were performed at baseline and follow-up. Patients were classified (blinded to MRI and clinical data) as impaired or unimpaired in each domain using predefined criteria. We compared the prevalence of cognitive impairments in each domain at baseline and follow-up and investigated clinical and radiological predictors [including baseline CMBs and white matter changes (WMCs)] of frontal-executive cognitive impairment. RESULTS: Of the original cohort of 55 patients, 13 died without follow-up. Twenty-six of the surviving patients (9 with, 17 without baseline CMBs) agreed to follow-up neuropsychological assessment; 21 of these patients had a repeat MRI scan. The median number of cognitive domains impaired increased, regardless of the presence of baseline CMBs (with baseline CMBs: median 3, range 0-5 at follow-up vs. median 2, range 0-2 at baseline, p = 0.016; without CMBs: median 1.0, range 0-5 at follow-up vs. median 0, range 0-5 at baseline, p = 0.035). Frontal-executive impairment at follow-up was more prevalent in patients with baseline CMBs than in those without (78 vs. 29%, p = 0.038). The presence of baseline CMBs predicted frontal-executive impairment at follow-up (OR 8.40, 95% CI 1.27-55.39, p = 0.027). Fifty percent of patients with CMBs versus 8% of patients without baseline CMBs developed new CMBs (p = 0.047). The severity of WMCs increased; the difference was statistically significant only in patients without baseline CMBs (p = 0.027). There were no new cortical infarcts. CONCLUSION: In stroke clinic patients, CMBs are consistently associated with frontal-executive impairment; baseline CMBs are associated with frontal-executive impairment at follow-up after 5.7 years. The presence of CMBs has prognostic relevance for long-term cognitive outcome in stroke clinic patients, and may help to optimally target preventive strategies in individuals at highest risk of cognitive decline.