Atrial Fibrillation Detected before or after Stroke: Role of Anticoagulation.

BACKGROUND: Atrial fibrillation (AF) known before ischemic stroke (KAF) has been postulated to be an independent category with a recurrence risk higher than that of AF detected after stroke (AFDAS). However, it is unknown whether this risk difference is confounded by pre-existing anticoagulation, which is most common in KAF and also indicates a high ischemic stroke recurrence risk. METHODS: Individual patient data analysis from 5 prospective cohorts of anticoagulated patients following AF-associated ischemic stroke. We compared the primary (ischemic stroke recurrence) and secondary outcome (all-cause death) among patients with AFDAS versus KAF and among anticoagulation-naïve versus previously anticoagulated patients using multivariable Cox, Fine-Gray models, and goodness-of-fit statistics to investigate the relative independent prognostic importance of AF-category and pre-existing anticoagulation. RESULTS: Of 4,357 patients, 1,889 (43%) had AFDAS and 2,468 (57%) had KAF, while 3,105 (71%) were anticoagulation-naïve before stroke and 1,252 (29%) were previously anticoagulated. During 6,071 patient-years of follow-up, we observed 244 recurrent strokes and 661 deaths. Only pre-existing anticoagulation (but not KAF) was independently associated with a higher hazard for stroke recurrence in both Cox and Fine-Gray models. Models incorporating pre-existing anticoagulation showed better fit than those with AF category; adding AF-category did not result in better model fit. Neither pre-existing anticoagulation nor KAF were independently associated with death. CONCLUSION: Our findings challenge the notion that KAF and AFDAS are clinically relevant and distinct prognostic entities. Instead of attributing an independently high stroke recurrence risk to KAF, future research should focus on the causes of stroke despite anticoagulation to develop improved preventive treatments. ANN NEUROL 2023;94:43-54.

Recent advances and controversial issues in the optimal management of asymptomatic carotid stenosis.

OBJECTIVE: The optimal management of patients with asymptomatic carotid stenosis (AsxCS) is enduringly controversial. We updated our 2021 Expert Review and Position Statement, focusing on recent advances in the diagnosis and management of patients with AsxCS. METHODS: A systematic review of the literature was performed up to August 1, 2023, using PubMed/PubMed Central, EMBASE and Scopus. The following keywords were used in various combinations: "asymptomatic carotid stenosis," "carotid endarterectomy" (CEA), "carotid artery stenting" (CAS), and "transcarotid artery revascularization" (TCAR). Areas covered included (i) improvements in best medical treatment (BMT) for patients with AsxCS and declining stroke risk, (ii) technological advances in surgical/endovascular skills/techniques and outcomes, (iii) risk factors, clinical/imaging characteristics and risk prediction models for the identification of high-risk AsxCS patient subgroups, and (iv) the association between cognitive dysfunction and AsxCS. RESULTS: BMT is essential for all patients with AsxCS, regardless of whether they will eventually be offered CEA, CAS, or TCAR. Specific patient subgroups at high risk for stroke despite BMT should be considered for a carotid revascularization procedure. These patients include those with severe (≥80%) AsxCS, transcranial Doppler-detected microemboli, plaque echolucency on Duplex ultrasound examination, silent infarcts on brain computed tomography or magnetic resonance angiography scans, decreased cerebrovascular reserve, increased size of juxtaluminal hypoechoic area, AsxCS progression, carotid plaque ulceration, and intraplaque hemorrhage. Treatment of patients with AsxCS should be individualized, taking into consideration individual patient preferences and needs, clinical and imaging characteristics, and cultural, ethnic, and social factors. Solid evidence supporting or refuting an association between AsxCS and cognitive dysfunction is lacking. CONCLUSIONS: The optimal management of patients with AsxCS should include BMT for all individuals and a prophylactic carotid revascularization procedure (CEA, CAS, or TCAR) for some asymptomatic patient subgroups, additionally taking into consideration individual patient needs and preference, clinical and imaging characteristics, social and cultural factors, and the available stroke risk prediction models. Future studies should investigate the association between AsxCS with cognitive function and the role of carotid revascularization procedures in the progression or reversal of cognitive dysfunction.

An international, multispecialty, expert-based Delphi Consensus document on controversial issues in the management of patients with asymptomatic and symptomatic carotid stenosis.

OBJECTIVE: Despite the publication of various national/international guidelines, several questions concerning the management of patients with asymptomatic (AsxCS) and symptomatic (SxCS) carotid stenosis remain unanswered. The aim of this international, multi-specialty, expert-based Delphi Consensus document was to address these issues to help clinicians make decisions when guidelines are unclear. METHODS: Fourteen controversial topics were identified. A three-round Delphi Consensus process was performed including 61 experts. The aim of Round 1 was to investigate the differing views and opinions regarding these unresolved topics. In Round 2, clarifications were asked from each participant. In Round 3, the questionnaire was resent to all participants for their final vote. Consensus was reached when ≥75% of experts agreed on a specific response. RESULTS: Most experts agreed that: (1) the current periprocedural/in-hospital stroke/death thresholds for performing a carotid intervention should be lowered from 6% to 4% in patients with SxCS and from 3% to 2% in patients with AsxCS; (2) the time threshold for a patient being considered "recently symptomatic" should be reduced from the current definition of "6 months" to 3 months or less; (3) 80% to 99% AsxCS carries a higher risk of stroke compared with 60% to 79% AsxCS; (4) factors beyond the grade of stenosis and symptoms should be added to the indications for revascularization in AsxCS patients (eg, plaque features of vulnerability and silent infarctions on brain computed tomography scans); and (5) shunting should be used selectively, rather than always or never. Consensus could not be reached on the remaining topics due to conflicting, inadequate, or controversial evidence. CONCLUSIONS: The present international, multi-specialty expert-based Delphi Consensus document attempted to provide responses to several unanswered/unresolved issues. However, consensus could not be achieved on some topics, highlighting areas requiring future research.

Thromboxane biosynthesis in cancer patients and its inhibition by aspirin: a sub-study of the Add-Aspirin trial.

BACKGROUND: Pre-clinical models demonstrate that platelet activation is involved in the spread of malignancy. Ongoing clinical trials are assessing whether aspirin, which inhibits platelet activation, can prevent or delay metastases. METHODS: Urinary 11-dehydro-thromboxane B2 (U-TXM), a biomarker of in vivo platelet activation, was measured after radical cancer therapy and correlated with patient demographics, tumour type, recent treatment, and aspirin use (100 mg, 300 mg or placebo daily) using multivariable linear regression models with log-transformed values. RESULTS: In total, 716 patients (breast 260, colorectal 192, gastro-oesophageal 53, prostate 211) median age 61 years, 50% male were studied. Baseline median U-TXM were breast 782; colorectal 1060; gastro-oesophageal 1675 and prostate 826 pg/mg creatinine; higher than healthy individuals (~500 pg/mg creatinine). Higher levels were associated with raised body mass index, inflammatory markers, and in the colorectal and gastro-oesophageal participants compared to breast participants (P < 0.001) independent of other baseline characteristics. Aspirin 100 mg daily decreased U-TXM similarly across all tumour types (median reductions: 77-82%). Aspirin 300 mg daily provided no additional suppression of U-TXM compared with 100 mg. CONCLUSIONS: Persistently increased thromboxane biosynthesis was detected after radical cancer therapy, particularly in colorectal and gastro-oesophageal patients. Thromboxane biosynthesis should be explored further as a biomarker of active malignancy and may identify patients likely to benefit from aspirin.

Testing to sustain hepatitis C elimination targets in people who inject drugs: A network-based model.

Little is known about the level of testing required to sustain elimination of hepatitis C (HCV), once achieved. In this study, we model the testing coverage required to maintain HCV elimination in an injecting network of people who inject drugs (PWID). We test the hypothesis that network-based strategies are a superior approach to deliver testing. We created a dynamic injecting network structure connecting 689 PWID based on empirical data. The primary outcome was the testing coverage required per month to maintain prevalence at the elimination threshold over 5 years. We compared four testing strategies. Without any testing or treatment provision, the prevalence of HCV increased from the elimination threshold (11.68%) to a mean of 25.4% (SD 2.96%) over the 5-year period. To maintain elimination with random testing, on average, 4.96% (SD 0.83%) of the injecting network needs to be tested per month. However, with a 'bring your friends' strategy, this was reduced to 3.79% (SD 0.64%) of the network (p < .001). The addition of contact tracing improved the efficiency of both strategies. In conclusion, we report that network-based approaches to testing such as 'bring a friend' initiatives and contact tracing lower the level of testing coverage required to maintain elimination.

Oral Anticoagulants in the Oldest Old with Recent Stroke and Atrial Fibrillation.

OBJECTIVE: To investigate the safety and effectiveness of direct oral anticoagulants (DOAC) versus vitamin K antagonists (VKA) after recent stroke in patients with atrial fibrillation (AF) aged ≥85 years. METHODS: Individual patient data analysis from seven prospective stroke cohorts. We compared DOAC versus VKA treatment among patients with AF and recent stroke (<3 months) aged ≥85 versus <85 years. Primary outcome was the composite of recurrent stroke, intracranial hemorrhage (ICH) and all-cause death. We used simple, adjusted, and weighted Cox regression to account for confounders. We calculated the net benefit of DOAC versus VKA by balancing stroke reduction against the weighted ICH risk. RESULTS: In total, 5,984 of 6,267 (95.5%) patients were eligible for analysis. Of those, 1,380 (23%) were aged ≥85 years and 3,688 (62%) received a DOAC. During 6,874 patient-years follow-up, the impact of anticoagulant type (DOAC versus VKA) on the hazard for the composite outcome did not differ between patients aged ≥85 (HR≥85y  = 0.65, 95%-CI [0.52, 0.81]) and < 85 years (HR<85y  = 0.79, 95%-CI [0.66, 0.95]) in simple (pinteraction  = 0.129), adjusted (pinteraction  = 0.094) or weighted (pinteraction  = 0.512) models. Analyses on recurrent stroke, ICH and death separately were consistent with the primary analysis, as were sensitivity analyses using age dichotomized at 90 years and as a continuous variable. DOAC had a similar net clinical benefit in patients aged ≥85 (+1.73 to +2.66) and < 85 years (+1.90 to +3.36 events/100 patient-years for ICH-weights 1.5 to 3.1). INTERPRETATION: The favorable profile of DOAC over VKA in patients with AF and recent stroke was maintained in the oldest old. ANN NEUROL 2022;91:78-88.

Long-term study of the cognitive profile of Moyamoya Disease in adults.

Moyamoya Disease (MMD) is a rare cerebrovascular disorder which can have significant cognitive consequences. The aim of the current study was to describe comprehensively the domain-specific cognitive profile of adult patients with MMD and to assess whether this changes in the absence of recurrent stroke over long-term follow-up. Comprehensive neuropsychological assessment covering seven cognitive domains was conducted on 61 adult patients with MMD at baseline and then at up to 3 further time points during follow up (median=2.31, 4.87 and 7.12 years). Although 27 patients had had prior surgical revasculariation, none had surgery between neuropsychological assessments. Cognitive impairment was common. At baseline, impairment in executive functions was most frequent (57%), followed by performance IQ (36%), speed of information processing (31%) and visual memory (30%). We found that the neuropsychological profile remains broadly stable over long-term follow-up with no clear indication of improvement or significant decline. The pattern of impairment also did not differ depending on age of onset or whether there was a history of either prior stroke at presentation or revascularisation surgery at presentation.

Absence of Consistent Sex Differences in Outcomes From Symptomatic Carotid Endarterectomy and Stenting Randomized Trials.

BACKGROUND AND PURPOSE: CREST (Carotid Revascularization Endarterectomy Versus Stenting Trial) reported a higher periprocedural risk for any stroke, death, or myocardial infarction for women randomized to carotid artery stenting (CAS) compared with women randomized to carotid endarterectomy (CEA). No difference in risk by treatment was detected for women relative to men in the 4-year primary outcome. We aimed to conduct a pooled analysis among symptomatic patients in large randomized trials to provide more precise estimates of sex differences in the CAS-to-CEA risk for any stroke or death during the 120-day periprocedural period and ipsilateral stroke thereafter. METHODS: Data from the Carotid Stenosis Trialists' Collaboration included outcomes from symptomatic patients in EVA-3S (Endarterectomy Versus Angioplasty in Patients With Symptomatic Severe Carotid Stenosis), SPACE (Stent-Protected Angioplasty Versus Carotid Endarterectomy in Symptomatic Patients), ICSS (International Carotid Stenting Study), and CREST. The primary outcome was any stroke or death within 120 days after randomization and ipsilateral stroke thereafter. Event rates and relative risks were estimated using Poisson regression; effect modification by sex was assessed with a sex-by-treatment-by-trial interaction term, with significant interaction defined a priori as P≤0.10. RESULTS: Over a median 2.7 years of follow-up, 433 outcomes occurred in 3317 men and 1437 women. The CAS-to-CEA relative risk of the primary outcome was significantly lower for women compared with men in 1 trial, nominally lower in another, and nominally higher in the other two. The sex-by-treatment-by-trial interaction term was significant (P=0.065), indicating heterogeneity among trials. Contributors to this heterogeneity are primarily differences in periprocedural period. When the trials are nevertheless pooled, there were no significant sex differences in risk in any follow-up period. CONCLUSIONS: There were significant differences between trials in the magnitude of sex differences in treatment effect (CAS-to-CEA relative risk), indicating pooling data from these trials to estimate sex differences might not be valid. Whether sex is acting as an effect modifier of the CAS-to-CEA treatment effect in symptomatic patients remains uncertain. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00190398 (EVA-3S) and NCT00004732 (CREST). URL: https://www.isrctn.com; Unique identifier: ISRCTN57874028 (SPACE) and ISRCTN25337470 (ICSS).

Small Vessel Disease and Ischemic Stroke Risk During Anticoagulation for Atrial Fibrillation After Cerebral Ischemia.

BACKGROUND AND PURPOSE: The causes of recurrent ischemic stroke despite anticoagulation for atrial fibrillation are uncertain but might include small vessel occlusion. We investigated whether magnetic resonance imaging markers of cerebral small vessel disease (SVD) are associated with ischemic stroke risk during follow-up in patients anticoagulated for atrial fibrillation after recent ischemic stroke or transient ischemic attack. METHODS: We analyzed data from a prospective multicenter inception cohort study of ischemic stroke or transient ischemic attack anticoagulated for atrial fibrillation (CROMIS-2 [Clinical Relevance of Microbleeds in Stroke Study]). We rated markers of SVD on baseline brain magnetic resonance imaging: basal ganglia perivascular spaces (number ≥11); cerebral microbleeds (number ≥1); lacunes (number ≥1); and white matter hyperintensities (periventricular Fazekas grade 3 or deep white matter Fazekas grade ≥2). We investigated the associations of SVD presence (defined as presence of ≥1 SVD marker) and severity (composite SVD score) with the risk of ischemic stroke during follow-up using a Cox proportional hazards model adjusted for congestive heart failure, hypertension, age >75, diabetes, stroke, vascular disease, age 65-74, female score. RESULTS: We included 1419 patients (mean age: 75.8 years [SD, 10.4]; 42.1% female). The ischemic stroke rate during follow-up in patients with any SVD was 2.20 per 100-patient years (95% CI, 1.60-3.02), compared with 0.98 per 100 patient-years (95% CI, 0.59-1.62) in those without SVD (P=0.008). After adjusting for congestive heart failure, hypertension, age >75, diabetes, stroke, vascular disease, age 65-74, female score, SVD presence remained significantly associated with ischemic stroke during follow-up (hazard ratio, 1.89 [95% CI, 1.01-3.53]; P=0.046); the risk of recurrent ischemic stroke increased with SVD score (hazard ratio per point increase, 1.33 [95% CI, 1.04-1.70]; P=0.023). CONCLUSIONS: In patients anticoagulated for atrial fibrillation after ischemic stroke or transient ischemic attack, magnetic resonance imaging markers of SVD are associated with an increased risk of ischemic stroke during follow-up; improved stroke prevention treatments are required in this population. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02513316.

Ischemic Stroke despite Oral Anticoagulant Therapy in Patients with Atrial Fibrillation.

OBJECTIVE: It is not known whether patients with atrial fibrillation (AF) with ischemic stroke despite oral anticoagulant therapy are at increased risk for further recurrent strokes or how ongoing secondary prevention should be managed. METHODS: We conducted an individual patient data pooled analysis of 7 prospective cohort studies that recruited patients with AF and recent cerebral ischemia. We compared patients taking oral anticoagulants (vitamin K antagonists [VKA] or direct oral anticoagulants [DOAC]) prior to index event (OACprior ) with those without prior oral anticoagulation (OACnaive ). We further compared those who changed the type (ie, from VKA or DOAC, vice versa, or DOAC to DOAC) of anticoagulation (OACchanged ) with those who continued the same anticoagulation as secondary prevention (OACunchanged ). Time to recurrent acute ischemic stroke (AIS) was analyzed using multivariate competing risk Fine-Gray models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: We included 5,413 patients (median age = 78 years [interquartile range (IQR) = 71-84 years]; 5,136 [96.7%] had ischemic stroke as the index event, median National Institutes of Health Stroke Scale on admission = 6 [IQR = 2-12]). The median CHA2 DS2 -Vasc score (congestive heart failure, hypertension, age≥ 75 years, diabetes mellitus, stroke/transient ischemic attack, vascular disease, age 65-74 years, sex category) was 5 (IQR = 4-6) and was similar for OACprior (n = 1,195) and OACnaive (n = 4,119, p = 0.103). During 6,128 patient-years of follow-up, 289 patients had AIS (4.7% per year, 95% CI = 4.2-5.3%). OACprior was associated with an increased risk of AIS (HR = 1.6, 95% CI = 1.2-2.3, p = 0.005). OACchanged (n = 307) was not associated with decreased risk of AIS (HR = 1.2, 95% CI = 0.7-2.1, p = 0.415) compared with OACunchanged (n = 585). INTERPRETATION: Patients with AF who have an ischemic stroke despite previous oral anticoagulation are at a higher risk for recurrent ischemic stroke despite a CHA2 DS2 -Vasc score similar to those without prior oral anticoagulation. Better prevention strategies are needed for this high-risk patient group. ANN NEUROL 2020.

Small vessel disease burden and intracerebral haemorrhage in patients taking oral anticoagulants.

OBJECTIVE: We investigated the contribution of small vessel disease (SVD) to anticoagulant-associated intracerebral haemorrhage (ICH). METHODS: Clinical Relevance of Microbleeds in Stroke-2 comprised two independent multicentre observation studies: first, a cross-sectional study of patients with ICH; and second, a prospective study of patients taking anticoagulants for atrial fibrillation (AF) after cerebral ischaemia. In patients with ICH, we compared SVD markers on CT and MRI according to prior anticoagulant therapy. In patients with AF and cerebral ischaemia treated with anticoagulants, we compared the rates of ICH and ischaemic stroke according to SVD burden score during 2 years follow-up. RESULTS: We included 1030 patients with ICH (421 on anticoagulants), and 1447 patients with AF and cerebral ischaemia. Medium-to-high severity SVD was more prevalent in patients with anticoagulant-associated ICH (CT 56.1%, MRI 78.7%) than in those without prior anticoagulant therapy (CT 43.5%, p<0.001; MRI 64.5%, p=0.072). Leukoaraiosis and atrophy were more frequent and severe in ICH associated with prior anticoagulation. In the cerebral ischaemia cohort (779 with SVD), during 3366 patient-years of follow-up the rate of ICH was 0.56%/year (IQR 0.27-1.03) in patients with SVD, and 0.06%/year (IQR 0.00-0.35) in those without (p=0.001); ICH was independently associated with severity of SVD (HR 5.0, 95% CI 1.9 to 12.2,p=0.001), and was predicted by models including SVD (c-index 0.75, 95% CI 0.63 to 0.85). CONCLUSIONS: Medium-to-high severity SVD is associated with ICH occurring on anticoagulants, and independently predicts ICH in patients with AF taking anticoagulants; its absence identifies patients at low risk of ICH. Findings from these two complementary studies suggest that SVD is a contributory factor in ICH in patients taking anticoagulants and suggest that anticoagulation alone should no longer be regarded as a sufficient 'cause' of ICH. TRIAL REGISTRATION: NCT02513316.

Long Term Restenosis Rate After Carotid Endarterectomy: Comparison of Three Surgical Techniques and Intra-Operative Shunt Use.

OBJECTIVE: Closure of the artery during carotid endarterectomy (CEA) can be done with or without a patch, or performed with the eversion technique, while the use of intra-operative shunts is optional. The influence of these techniques on subsequent restenosis is uncertain. Long term carotid restenosis rates and risk of future ipsilateral stroke with these techniques were compared. METHODS: Patients who underwent CEA in the International Carotid Stenting Study were divided into patch angioplasty, primary closure, or eversion endarterectomy. Intra-operative shunt use was reported. Carotid duplex ultrasound was performed at each follow up. Primary outcomes were restenosis of ≥ 50% and ≥ 70%, and ipsilateral stroke after the procedure to the end of follow up. RESULTS: In total, 790 CEA patients had restenosis data at one and five years. Altogether, 511 (64.7%) had patch angioplasty, 232 (29.4%) primary closure, and 47 (5.9%) eversion endarterectomy. The cumulative incidence of ≥ 50% restenosis at one year was 18.9%, 26.1%, and 17.7%, respectively, and at five years it was 25.9%, 37.2%, and 30.0%, respectively. There was no difference in risk between the eversion and patch angioplasty group (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.45 - 1.81; p = .77). Primary closure had a higher risk of restenosis than patch angioplasty (HR 1.45, 95% CI 1.06 - 1.98; p = .019). The cumulative incidence of ≥ 70% restenosis did not differ between primary closure and patch angioplasty (12.1% vs. 7.1%, HR 1.59, 95% CI 0.88 - 2.89; p = .12) or between patch angioplasty and eversion endarterectomy (4.7%, HR 0.45, 95% CI 0.06 - 3.35; p = .44). There was no effect of shunt use on the cumulative incidence of restenosis. Post-procedural ipsilateral stroke was not more common in either of the surgical techniques or shunt use. CONCLUSION: Restenosis was more common after primary closure than conventionally with a patch closure. Shunt use had no effect on restenosis. Patch closure is the treatment of choice to avoid restenosis.

Editor's Choice - Risk of Stroke before Revascularisation in Patients with Symptomatic Carotid Stenosis: A Pooled Analysis of Randomised Controlled Trials.

OBJECTIVE: Current guidelines recommending rapid revascularisation of symptomatic carotid stenosis are largely based on data from clinical trials performed at a time when best medical therapy was potentially less effective than today. The risk of stroke and its predictors among patients with symptomatic carotid stenosis awaiting revascularisation in recent randomised controlled trials (RCTs) and in medical arms of earlier RCTs was assessed. METHODS: The pooled data of individual patients with symptomatic carotid stenosis randomised to stenting (CAS) or endarterectomy (CEA) in four recent RCTs, and of patients randomised to medical therapy in three earlier RCTs comparing CEA vs. medical therapy, were compared. The primary outcome event was any stroke occurring between randomisation and treatment by CAS or CEA, or within 120 days after randomisation. RESULTS: A total of 4 754 patients from recent trials and 1 227 from earlier trials were included. In recent trials, patients were randomised a median of 18 (IQR 7, 50) days after the qualifying event (QE). Twenty-three suffered a stroke while waiting for revascularisation (cumulative 120 day risk 1.97%, 95% confidence interval [CI] 0.75 - 3.17). Shorter time from QE until randomisation increased stroke risk after randomisation (χ2 = 6.58, p = .011). Sixty-one patients had a stroke within 120 days of randomisation in the medical arms of earlier trials (cumulative risk 5%, 95% CI 3.8 - 6.2). Stroke risk was lower in recent than earlier trials when adjusted for time between QE and randomisation, age, severity of QE, and degree of carotid stenosis (HR 0.47, 95% CI 0.25 - 0.88, p = .019). CONCLUSION: Patients with symptomatic carotid stenosis enrolled in recent large RCTs had a lower risk of stroke after randomisation than historical controls. The added benefit of carotid revascularisation to modern medical care needs to be revisited in future studies. Until then, adhering to current recommendations for early revascularisation of patients with symptomatic carotid stenosis considered to require invasive treatment is advisable.

Inspiratory Muscle Training Improves Inspiratory Muscle Strength and Functional Exercise Capacity in Pulmonary Arterial Hypertension and Chronic Thromboembolic Pulmonary Hypertension: A Pilot Randomised Controlled Study.

BACKGROUND: Exercise intolerance is present even in the early stages of pulmonary arterial hypertension (PAH) and is associated with poorer prognosis. Respiratory muscle dysfunction is common and may contribute to exercise limitation. We sought to investigate the effects of inspiratory muscle training (IMT) to improve exercise capacity in PAH. METHODS: Adults with PAH were prospectively recruited and randomly assigned to either IMT or a control group. At baseline and after 8 weeks, assessment of respiratory muscle function, pulmonary function, neurohormonal activation, 6-minute walk distance and cardiopulmonary exercise testing variables were conducted. Inspiratory muscle strength was assessed by maximal static inspiratory pressure (PImax). The IMT group performed two cycles of 30 breaths at 30-40% of their PImax 5 days a week for 8 weeks. RESULTS: Twelve (12) PAH patients (60±14 years, 10 females) were recruited and randomised (six in the IMT group and six in the control group). After 8 weeks, the IMT group improved PImax by 31 cmH2O compared with 10 cmH2O in controls, p=0.02. Following IMT, 6-minute walk distance improved by 24.5 m in the IMT group and declined by 12 m in the controls (mean difference 36.5 m, 95% CI 3.5-69.5, p=0.03). There was no difference in peak oxygen uptake between-groups (mean difference 0.4 mL/kg/min, 95% CI -2.6 to 3.4, p=0.77). There was no difference in the mean change between-groups in neurohormonal activation or pulmonary function. CONCLUSION: In this pilot randomised controlled study, IMT improved PImax and 6-minute walk distance in PAH patients.

Arterial Spin Labeling MRI in Carotid Stenosis: Arterial Transit Artifacts May Predict Symptoms.

BackgroundStenosis of the internal carotid artery has a higher risk for stroke. Many investigations have focused on structure and plaque composition as signs of plaque vulnerability, but few studies have analyzed hemodynamic changes in the brain as a risk factor.PurposeTo use 3-T MRI methods including contrast material-enhanced MR angiography, carotid plaque imaging, and arterial spin labeling (ASL) to identify imaging parameters that best help distinguish between asymptomatic and symptomatic participants with carotid stenosis.Materials and MethodsParticipants with carotid stenosis from two ongoing prospective studies who underwent ASL and carotid plaque imaging with use of 3-T MRI in the same setting from 2014 to 2018 were studied. Participants were assessed clinically for recent symptoms (transient ischemic attack or stroke) and divided equally into symptomatic and nonsymptomatic groups. Reviewers were blinded to the symptomatic status and MRI scans were analyzed for the degree of stenosis, plaque surface structure, presence of intraplaque hemorrhage (IPH), circle of Willis collaterals, and the presence and severity of arterial transit artifacts (ATAs) at ASL imaging. MRI findings were correlated with symptomatic status by using t tests and the Fisher exact test.ResultsA total of 44 participants (mean age, 71 years ± 10 [standard deviation]; 31 men) were evaluated. ATAs were seen only in participants with greater than 70% stenosis (16 of 28 patients; P < .001) and were associated with absence of anterior communicating artery (13 of 16 patients; P = .003). There was no association between history of symptoms and degree of stenosis (27 patients with ≥70% stenosis and 17 patients with <70%; P = .54), IPH (12 patients with IPH and 32 patients without IPH; P = .31), and plaque surface structure (17 patients with irregular or ulcerated plaque and 27 with smooth plaque; P = .54). Participants with ATAs (n = 16) were more likely to be symptomatic than were those without ATAs (n = 28) (P = .004). Symptomatic status also was associated with the severity of ATAs (P = .002).ConclusionArterial transit artifacts were the only factor associated with recent ischemic symptoms in participants with carotid stenosis. The degree of stenosis, plaque ulceration, and intraplaque hemorrhage were not associated with symptomatic status.© RSNA, 2020Online supplemental material is available for this article.See also the editorial by Zaharchuk in this issue.

Direct oral anticoagulants versus vitamin K antagonists after recent ischemic stroke in patients with atrial fibrillation.

OBJECTIVE: We compared outcomes after treatment with direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs) in patients with atrial fibrillation (AF) and a recent cerebral ischemia. METHODS: We conducted an individual patient data analysis of seven prospective cohort studies. We included patients with AF and a recent cerebral ischemia (<3 months before starting oral anticoagulation) and a minimum follow-up of 3 months. We analyzed the association between type of anticoagulation (DOAC versus VKA) with the composite primary endpoint (recurrent ischemic stroke [AIS], intracerebral hemorrhage [ICH], or mortality) using mixed-effects Cox proportional hazards regression models; we calculated adjusted hazard ratios (HRs) with 95% confidence intervals (95% CIs). RESULTS: We included 4,912 patients (median age, 78 years [interquartile range {IQR}, 71-84]; 2,331 [47.5%] women; median National Institute of Health Stroke Severity Scale at onset, 5 [IQR, 2-12]); 2,256 (45.9%) patients received VKAs and 2,656 (54.1%) DOACs. Median time from index event to starting oral anticoagulation was 5 days (IQR, 2-14) for VKAs and 5 days (IQR, 2-11) for DOACs (p = 0.53). There were 262 acute ischemic strokes (AISs; 4.4%/year), 71 intracranial hemorrrhages (ICHs; 1.2%/year), and 439 deaths (7.4%/year) during the total follow-up of 5,970 patient-years. Compared to VKAs, DOAC treatment was associated with reduced risks of the composite endpoint (HR, 0.82; 95% CI, 0.67-1.00; p = 0.05) and ICH (HR, 0.42; 95% CI, 0.24-0.71; p < 0.01); we found no differences for the risk of recurrent AIS (HR, 0.91; 95% CI, 0.70-1.19; p = 0.5) and mortality (HR, 0.83; 95% CI, 0.68-1.03; p = 0.09). INTERPRETATION: DOAC treatment commenced early after recent cerebral ischemia related to AF was associated with reduced risk of poor clinical outcomes compared to VKA, mainly attributed to lower risks of ICH. ANN NEUROL 2019;85:823-834.

Longer term stroke risk in intracerebral haemorrhage survivors.

OBJECTIVE: To evaluate the influence of intracerebral haemorrhage (ICH) location on stroke outcomes. METHODS: We included patients recruited to a UK hospital-based, multicentre observational study of adults with imaging confirmed spontaneous ICH. The outcomes of interest were occurrence of a cerebral ischaemic event (either stroke or transient ischaemic attack) or a further ICH following study entry. Haematoma location was classified as lobar or non-lobar. RESULTS: All 1094 patients recruited to the CROMIS-2 (Clinical Relevance of Microbleeds in Stroke) ICH study were included (mean age 73.3 years; 57.4% male). There were 45 recurrent ICH events (absolute event rate (AER) 1.88 per 100 patient-years); 35 in patients presenting with lobar ICH (n=447, AER 3.77 per 100 patient-years); and 9 in patients presenting with non-lobar ICH (n=580, AER 0.69 per 100 patient-years). Multivariable Cox regression found that lobar ICH was associated with ICH recurrence (HR 8.96, 95% CI 3.36 to 23.87, p<0.0001); similar results were found in multivariable completing risk analyses. There were 70 cerebral ischaemic events (AER 2.93 per 100 patient-years); 29 in patients presenting with lobar ICH (AER 3.12 per 100 patient-years); and 39 in patients with non-lobar ICH (AER 2.97 per 100 patient-years). Multivariable Cox regression found no association with ICH location (HR 1.13, 95% CI 0.66 to 1.92, p = 0.659). Similar results were seen in completing risk analyses. CONCLUSIONS: In ICH survivors, lobar ICH location was associated with a higher risk of recurrent ICH events than non-lobar ICH; ICH location did not influence risk of subsequent ischaemic events. TRIAL REGISTRATION NUMBER: NCT02513316.

Haptoglobin genotype and outcome after aneurysmal subarachnoid haemorrhage.

OBJECTIVE: After aneurysmal subarachnoid haemorrhage (aSAH), extracellular haemoglobin (Hb) in the subarachnoid space is bound by haptoglobin, neutralising Hb toxicity and helping its clearance. Two exons in the HP gene (encoding haptoglobin) exhibit copy number variation (CNV), giving rise to HP1 and HP2 alleles, which influence haptoglobin expression level and possibly haptoglobin function. We hypothesised that the HP CNV associates with long-term outcome beyond the first year after aSAH. METHODS: The HP CNV was typed using quantitative PCR in 1299 aSAH survivors in the Genetics and Observational Subarachnoid Haemorrhage (GOSH) Study, a retrospective multicentre cohort study with a median follow-up of 18 months. To investigate mediation of the HP CNV effect by haptoglobin expression level, as opposed to functional differences, we used rs2000999, a single nucleotide polymorphism associated with haptoglobin expression independent of the HP CNV. Outcome was assessed using modified Rankin and Glasgow Outcome Scores. SAH volume was dichotomised on the Fisher grade. Haemoglobin-haptoglobin complexes were measured in cerebrospinal fluid (CSF) of 44 patients with aSAH and related to the HP CNV. RESULTS: The HP2 allele associated with a favourable long-term outcome after high-volume but not low-volume aSAH (multivariable logistic regression). However rs2000999 did not predict outcome. The HP2 allele associated with lower CSF haemoglobin-haptoglobin complex levels. The CSF Hb concentration after high-volume and low-volume aSAH was, respectively, higher and lower than the Hb-binding capacity of CSF haptoglobin. CONCLUSION: The HP2 allele carries a favourable long-term prognosis after high-volume aSAH. Haptoglobin and the Hb clearance pathway are therapeutic targets after aSAH.

Haptoglobin genotype and outcome after spontaneous intracerebral haemorrhage.

OBJECTIVE: Haptoglobin is a haemoglobin-scavenging protein that binds and neutralises free haemoglobin and modulates inflammation and endothelial progenitor cell function. A HP gene copy number variation (CNV) generates HP1 and HP2 alleles, while the single-nucleotide polymorphism rs2000999 influences their levels. The HP1 allele is hypothesised to improve outcome after spontaneous (non-traumatic) intracerebral haemorrhage (ICH). We investigated the associations of the HP CNV genotype and rs2000999 with haematoma volume, perihaematomal oedema (PHO) volume, functional outcome and mortality after ICH. METHODS: We included patients with neuroimaging-proven ICH, available DNA and 6-month follow-up in an observational cohort study (CROMIS-2). We classified patients into three groups according to the HP CNV: 1-1, 2-1 or 2-2 and also dichotomised HP into HP1-containing genotypes (HP1-1 and HP2-1) and HP2-2 to evaluate the HP1 allele. We measured ICH and PHO volume on CT; PHO was measured by oedema extension distance. Functional outcome was assessed by modified Rankin score (unfavourable outcome defined as mRS 3-6). RESULTS: We included 731 patients (mean age 73.4, 43.5% female). Distribution of HP CNV genotype was: HP1-1 n=132 (18.1%); HP2-1 n=342 (46.8%); and HP2-2 n=257 (35.2%). In the multivariable model mortality comparisons between HP groups, HP2-2 as reference, were as follows: OR HP1-1 0.73, 95% CI 0.34 to 1.56 (p value=0.41) and OR HP2-1 0.5, 95% CI 0.28 to 0.89 (p value=0.02) (overall p value=0.06). We found no evidence of association of HP CNV or rs200999 with functional outcome, ICH volume or PHO volume. CONCLUSION: The HP2-1 genotype might be associated with lower 6-month mortality after ICH; this finding merits further study.

Carotid artery stenting versus endarterectomy for treatment of carotid artery stenosis.

BACKGROUND: Carotid artery stenting is an alternative to carotid endarterectomy for the treatment of atherosclerotic carotid artery stenosis. This review updates a previous version first published in 1997 and subsequently updated in 2004, 2007, and 2012. OBJECTIVES: To assess the benefits and risks of stenting compared with endarterectomy in people with symptomatic or asymptomatic carotid stenosis. SEARCH METHODS: We searched the Cochrane Stroke Group Trials Register (last searched August 2018) and the following databases: CENTRAL, MEDLINE, Embase, and Science Citation Index to August 2018. We also searched ongoing trials registers (August 2018) and reference lists, and contacted researchers in the field. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing stenting with endarterectomy for symptomatic or asymptomatic atherosclerotic carotid stenosis. In addition, we included RCTs comparing carotid artery stenting with medical therapy alone. DATA COLLECTION AND ANALYSIS: One review author selected trials for inclusion, assessed trial quality and risk of bias, and extracted data. A second review author independently validated trial selection and a third review author independently validated data extraction. We calculated treatment effects as odds ratios (OR) and 95% confidence intervals (CI), with endarterectomy as the reference group. We quantified heterogeneity using the I² statistic and used GRADE to assess the overall certainty of evidence. MAIN RESULTS: We included 22 trials involving 9753 participants. In participants with symptomatic carotid stenosis, compared with endarterectomy stenting was associated with a higher risk of periprocedural death or stroke (the primary safety outcome; OR 1.70, 95% CI 1.31 to 2.19; P < 0.0001, I² = 5%; 10 trials, 5396 participants; high-certainty evidence); and periprocedural death, stroke, or myocardial infarction (OR 1.43, 95% CI 1.14 to 1.80; P = 0.002, I² = 0%; 6 trials, 4861 participants; high-certainty evidence). The OR for the primary safety outcome was 1.11 (95% CI 0.74 to 1.64) in participants under 70 years old and 2.23 (95% CI 1.61 to 3.08) in participants 70 years old or more (interaction P = 0.007). There was a non-significant increase in periprocedural death or major or disabling stroke with stenting (OR 1.36, 95% CI 0.97 to 1.91; P = 0.08, I² = 0%; 7 trials, 4983 participants; high-certainty evidence). Compared with endarterectomy, stenting was associated with lower risks of myocardial infarction (OR 0.47, 95% CI 0.24 to 0.94; P = 0.03, I² = 0%), cranial nerve palsy (OR 0.09, 95% CI 0.06 to 0.16; P < 0.00001, I² = 0%), and access site haematoma (OR 0.32, 95% CI 0.15 to 0.68; P = 0.003, I² = 27%). The combination of periprocedural death or stroke or ipsilateral stroke during follow-up (the primary combined safety and efficacy outcome) favoured endarterectomy (OR 1.51, 95% CI 1.24 to 1.85; P < 0.0001, I² = 0%; 8 trials, 5080 participants; high-certainty evidence). The rate of ipsilateral stroke after the periprocedural period did not differ between treatments (OR 1.05, 95% CI 0.75 to 1.47; P = 0.77, I² = 0%). In participants with asymptomatic carotid stenosis, there was a non-significant increase in periprocedural death or stroke with stenting compared with endarterectomy (OR 1.72, 95% CI 1.00 to 2.97; P = 0.05, I² = 0%; 7 trials, 3378 participants; moderate-certainty evidence). The risk of periprocedural death or stroke or ipsilateral stroke during follow-up did not differ significantly between treatments (OR 1.27, 95% CI 0.87 to 1.84; P = 0.22, I² = 0%; 6 trials, 3315 participants; moderate-certainty evidence). Moderate or higher carotid artery restenosis (50% or greater) or occlusion during follow-up was more common after stenting (OR 2.00, 95% CI 1.12 to 3.60; P = 0.02, I² = 44%), but the difference in risk of severe restenosis was not significant (70% or greater; OR 1.26, 95% CI 0.79 to 2.00; P = 0.33, I² = 58%; low-certainty evidence). AUTHORS' CONCLUSIONS: Stenting for symptomatic carotid stenosis is associated with a higher risk of periprocedural stroke or death than endarterectomy. This extra risk is mostly attributed to an increase in minor, non-disabling strokes occurring in people older than 70 years. Beyond the periprocedural period, carotid stenting is as effective in preventing recurrent stroke as endarterectomy. However, combining procedural safety and long-term efficacy in preventing recurrent stroke still favours endarterectomy. In people with asymptomatic carotid stenosis, there may be a small increase in the risk of periprocedural stroke or death with stenting compared with endarterectomy. However, CIs of treatment effects were wide and further data from randomised trials in people with asymptomatic stenosis are needed.