The PASTIS trial: Testing tadalafil for possible use in vascular cognitive impairment.

INTRODUCTION: There are few randomized clinical trials in vascular cognitive impairment (VCI). This trial tested the hypothesis that the PDE5 inhibitor tadalafil, a widely used vasodilator, increases cerebral blood flow (CBF) in older people with symptomatic small vessel disease, the main cause of VCI. METHODS: In a double-blind, placebo-controlled, cross-over trial, participants received tadalafil (20 mg) and placebo on two visits ≥7 days apart (randomized to order of treatment). The primary endpoint, change in subcortical CBF, was measured by arterial spin labelling. RESULTS: Tadalafil increased CBF non-significantly in all subcortical areas (N = 55, age: 66.8 (8.6) years) with greatest treatment effect within white matter hyperintensities (+9.8%, P = .0960). There were incidental treatment effects on systolic and diastolic blood pressure (-7.8, -4.9 mmHg; P < .001). No serious adverse events were observed. DISCUSSION: This trial did not identify a significant treatment effect of single-administration tadalafil on subcortical CBF. To detect treatment effects may require different dosing regimens.

Using DTI to assess white matter microstructure in cerebral small vessel disease (SVD) in multicentre studies.

Diffusion tensor imaging (DTI) metrics such as fractional anisotropy (FA) and mean diffusivity (MD) have been proposed as clinical trial markers of cerebral small vessel disease (SVD) due to their associations with outcomes such as cognition. However, studies investigating this have been predominantly single-centre. As clinical trials are likely to be multisite, further studies are required to determine whether associations with cognition of similar strengths can be detected in a multicentre setting. One hundred and nine patients (mean age =68 years) with symptomatic lacunar infarction and confluent white matter hyperintensities (WMH) on MRI was recruited across six sites as part of the PRESERVE DTI substudy. After handling missing data, 3T-MRI scanning was available from five sites on five scanner models (Siemens and Philips), alongside neuropsychological and quality of life (QoL) assessments. FA median and MD peak height were extracted from DTI histogram analysis. Multiple linear regressions were performed, including normalized brain volume, WMH lesion load, and n° lacunes as covariates, to investigate the association of FA and MD with cognition and QoL. DTI metrics from all white matter were significantly associated with global cognition (standardized ß =0.268), mental flexibility (ß =0.306), verbal fluency (ß =0.376), and Montreal Cognitive Assessment (MoCA) (ß =0.273). The magnitudes of these associations were comparable with those previously reported from single-centre studies found in a systematic literature review. In this multicentre study, we confirmed associations between DTI parameters and cognition, which were similar in strength to those found in previous single-centre studies. The present study supports the use of DTI metrics as biomarkers of disease progression in multicentre studies.

Decompressive craniectomy for the treatment of malignant middle cerebral artery infarction.

INTRODUCTION: Malignant middle cerebral artery (MCA) infarction is associated with up to 80% mortality in the first week, despite maximal medical therapy. Decompressive craniectomy (DC) has been shown to improve survival rates in these patients. However, there are concerns that DC prolongs poor quality of life by increasing the number of survivors with major disability. This review will assess if DC in patients with malignant MCA infarction improves functional outcomes compared to maximal medical therapy. It will estimate the optimal time for surgery following stroke onset and ask if DC is effective in older patients (>60 years). METHODS: A literature search was conducted using Medline, Embase, PubMed and the Cochrane Library. Randomised controlled trials and meta-analysis that fulfilled the inclusion criteria and answered the clinical question were evaluated. RESULTS: Twelve papers were identified and considered appropriate to answer the clinical question. These included 8 prospective randomised controlled trials and 4 meta-analysis. A critical review of these papers was conducted. CONCLUSIONS: In patients 60 years of age or younger, DC within 48 hours of stroke onset significantly reduced risk of death and major disability (mRS >3) compared to maximal medical therapy only. In older patients (>60 years) DC also significantly improved survival but the majority of survivors were left with major disability (mRS 4-5). DC performed more than 48 hours after symptom onset does not appear to be superior to best medical management. The decision to perform decompressive surgery needs to be made on a case-by-case basis, taking into account the degree of disability patients and their carers are willing to accept.

An Uncommon Cause of Stroke: Non-bacterial Thrombotic Endocarditis.

Our objective is to present the case of an uncommon but probably under-recognized cause of stroke: Non-bacterial thrombotic endocarditis (NBTE). A 59-year-old man presented to our hospital with multiple bihemispheric infarcts despite taking rivaroxaban for pulmonary emboli diagnosed 2 weeks earlier. The patient's symptoms progressed quickly and he died within a week of his initial presentation despite attempts at neuroradiologically guided clot retrieval and early recognition and treatment of disseminated intravascular coagulation. On postmortem examination it was discovered that he had an undiagnosed squamous cell adenocarcinoma of the lung and NBTE. NBTE is difficult to diagnose and difficult to treat. It is associated with a mortality rate and is often not diagnosed until autopsy. However there are case reports in the literature where NBTE has been successfully treated. Early recognition and prompt treatment of the underlying disease process is the essential first step.

Rheumatoid meningitis.

Rheumatoid meningitis is a rare, potentially treatable condition that can mimic a wide range of neurological conditions, including vascular syndromes and encephalopathies. Despite a concurrent history of rheumatoid arthritis, patients often have no active synovitis. Here we describe a patient with rheumatoid meningitis who presented to a hyperacute stroke unit with dysarthria on waking and transient facial droop.

User experience of a centralized hyperacute stroke service: a prospective evaluation.

BACKGROUND AND PURPOSE: Centralizing hyperacute stroke unit (HASU) care services allows improved access to thrombolysis but could be associated with worse patient experience, particularly when early repatriation to a local stroke recovery unit occurs as this may result in discontinuity of care. A centralized model of care was introduced in London, United Kingdom, with 8 HASUs providing acute care for the whole 8.3 million population, with repatriation on day 3 to a local stroke recovery unit. The patient and carer experience of this model of care has not been previously reported. METHODS: We undertook a prospective observational study of the new model of care in the South West London sector. Patient and carer experiences were evaluated using a modified Picker Questionnaire. Separate questionnaires were used for patients discharged directly home from the HASU, those repatriated to local stroke recovery units, and for carers of patients admitted to the HASU. RESULTS: Despite moving from a selected to nonselected admission pattern, thrombolysis rates increased from 6% to 9%. High satisfaction rates were reported among both patients and carers. Patients discharged directly home had higher satisfaction levels than those requiring repatriation to their local stroke unit, who were older and had more severe stroke. A total of 47% of carers expressed anxiety over the repatriation from the HASU back to the local stroke recovery unit, but few patients and carers reported an impact of this move on patient recovery. CONCLUSION: Centralized HASU care is associated with good levels of patient and carer satisfaction.

Testing the cognitive effects of tadalafil. Neuropsychological secondary outcomes from the PASTIS trial.

Cerebral small vessel disease (SVD) is a major cause of cognitive impairment in older people. As secondary endpoints in a phase-2 randomised clinical trial, we tested the effects of single administration of a widely-used PDE5 inhibitor, tadalafil, on cognitive performance in older people with SVD. In a double-blinded, placebo-controlled, cross-over trial, participants received tadalafil (20 mg) and placebo on two visits ≥ 7 days apart (randomised to order of treatment). The Montreal Cognitive Assessment (MOCA) was administered at baseline, alongside a measure to estimate optimal intellectual ability (Test of Premorbid Function). Then, before and after treatment, a battery of neuropsychological tests was administered, assessing aspects of attention, information processing speed, working memory and executive function. Sixty-five participants were recruited and 55 completed the protocol (N = 55, age: 66.8 (8.6) years, range 52-87; 15/40 female/male). Median MOCA score was 26 (IQR: 23, 27], range 15-30). No significant treatment effects were seen in any of the neuropsychological tests. There was a trend towards improved performance on Digit Span Forward (treatment effect 0.37, C.I. 0.01, 0.72; P = 0.0521). We did not identify significant treatment effects of single-administration tadalafil on neuropsychological performance in older people with SVD. The trend observed on Digit Span Forward may help to inform future studies. Clinical trial registration: http://www.clinicaltrials.gov. Unique identifier: NCT00123456, https://eudract.ema.europa.eu. Unique identifier: 2015-001,235-20NCT00123456.

Test-retest reliability of arterial spin labelling for cerebral blood flow in older adults with small vessel disease.

Cerebral small vessel disease (SVD) is common in older people and is associated with lacunar stroke, white matter hyperintensities (WMH) and vascular cognitive impairment. Cerebral blood flow (CBF) is reduced in SVD, particularly within white matter.Here we quantified test-retest reliability in CBF measurements using pseudo-continuous arterial spin labelling (pCASL) in older adults with clinical and radiological evidence of SVD (N=54, mean (SD): 66.9 (8.7) years, 15 females/39 males). We generated whole-brain CBF maps on two visits at least 7 days apart (mean (SD): 20 (19), range 7-117 days).Test-retest reliability for CBF was high in all tissue types, with intra-class correlation coefficient [95%CI]: 0.758 [0.616, 0.852] for whole brain, 0.842 [0.743, 0.905] for total grey matter, 0.771 [0.636, 0.861] for deep grey matter (caudate-putamen and thalamus), 0.872 [0.790, 0.923] for normal-appearing white matter (NAWM) and 0.780 [0.650, 0.866] for WMH (all p<0.001). ANCOVA models indicated significant decline in CBF in total grey matter, deep grey matter and NAWM with increasing age and diastolic blood pressure (all p<0.001). CBF was lower in males relative to females (p=0.013 for total grey matter, p=0.004 for NAWM).We conclude that pCASL has high test-retest reliability as a quantitative measure of CBF in older adults with SVD. These findings support the use of pCASL in routine clinical imaging and as a clinical trial endpoint.All data come from the PASTIS trial, prospectively registered at: https://eudract.ema.europa.eu (2015-001235-20, registered 13/05/2015), http://www.clinicaltrials.gov (NCT02450253, registered 21/05/2015).

FAST positive does not always mean stroke.

Patients who are face, arm, speech test (FAST) positive may have a stroke mimic diagnosis. Careful attention to the speed of onset of symptoms is paramount. Magnetic resonance imaging is helpful in supplementing the clinical assessment.

Shoulder pain after recent stroke (SPARS): hemiplegic shoulder pain incidence within 72hours post-stroke and 8-10 week follow-up (NCT 02574000).

OBJECTIVES: This study aimed to identify very early incidence of hemiplegic shoulder pain within 72hours (HSP), how clinical assessment was related to pain at 8-10 week follow-up and explore current standard therapy/management. DESIGN: Observational, prospective. SETTING: Teaching hospital hyper-acute and follow-up stroke services. PARTICIPANTS: 121 consecutive patients with confirmed cerebral infarct/haemorrhage recruited within 72hours of stroke onset. INTERVENTIONS: N/A. MAIN OUTCOME MEASURES: Subjective report of pain severity and aggravating factors: using numerical rating scales and pain questionnaire (ShoulderQ), shoulder abductor and flexor muscle strength (Oxford MRC Scale), Neer's Test of sub-acromial pain, shoulder subluxation and soft tissue shoulder palpation. RESULTS: At initial assessment (<72hours), 35% (42/121) reported HSP. At follow-up (8-10 weeks), 44% (53/121) had pain: pain persisted in 32 of the original 42, resolved in 10 and had developed since initial assessment in 21. Pain at follow-up was associated with a statistically significant higher frequency of severe shoulder muscle weakness (MRC grade ≤2) and gleno-humeral subluxation at initial assessment. Soft tissue palpation and Neer's Test detected pain but did not predict development of HSP. 50/121 patients had 140 therapy interventions, particularly targeted to those with a higher HSP risk. CONCLUSION: This study reports HSP at an earlier time point after stroke than previous publications. Patients with severe arm weakness and/or shoulder subluxation within 72hours are at significantly higher risk of HSP at 8-10 weeks. These data highlight the high incidence of HSP, the non-standardized therapy approach, and can inform sample size calculations for future intervention studies. CLINICAL TRIAL REGISTRATION: NCT02574000 (clinicaltrials.gov).

Early repatriation post-thrombectomy: a model of care which maximises the capacity of a stroke network to treat patients with large vessel ischaemic stroke.

BACKGROUND AND PURPOSE: Healthcare systems are challenged to provide access to thrombectomy in acute stroke patients. Either the "drip and ship" or "mothership" models result in increased numbers of patients in the endovascular stroke centre (ESC). We describe our approach for a "drip, ship, retrieve and leave" model repatriating patients immediately or within 24 hours of thrombectomy. METHODS: We included consecutive patients who underwent thrombectomy from January 2016 to June 2018. Patients from local region primary stroke centres (PSC) are immediately repatriated and those from remote region PSCs are admitted for 24 hours before repatriation. Key parameters recorded included clinical, radiological and timeline data as well as 90-day modified Rankin Scale (mRS). Patients who stayed beyond the intended time period in the ESC were analysed. RESULTS: From January 2016 to June 2018, 435 patients were transferred, with 352 patients in the local region group and 83 in the remote region group. The median NIHSS was 16 with a median ASPECTS of 9. Good functional outcome was seen in 47% of patients with a mortality rate of 19%. The local region group that were repatriated at the intended time period had a 90-day mRS 0-2 of 47% compared with 20% of those admitted to the ESC (P=0.006). Mortality rates were 20% and 27% respectively (P=0.377). The remote region group, repatriated at 24 hours' post-emergency endovascular thrombectomy had 90-day mRS 0-2 of 65% compared with 41% in the group admitted (P=0.042). Mortality rates were 4% and 22% respectively (P=0.007). CONCLUSION: This model enables the treatment of large numbers of patients with large vessel occlusion acute ischaemic stroke with thrombectomy within a national stroke service and system of care which would not otherwise be facilitated.

Role of the cystic fibrosis transmembrane conductance channel in human airway smooth muscle.

Patients with cystic fibrosis (CF) suffer from asthma-like symptoms and gastrointestinal cramps, attributed to a mutation in the CF transmembrane conductance regulator (CFTR) gene present in a variety of cells. Pulmonary manifestations of the disease include the production of thickened mucus and symptoms of asthma, such as cough and wheezing. A possible alteration in airway smooth muscle (ASM) cell function of patients with CF has not been investigated. The aim of this study was to determine whether the (CFTR) channel is present and affects function of human ASM cells. Cell cultures were obtained from the main or lobar bronchi of patients with and without CF, and the presence of the CFTR channel detected by immunofluorescence. Cytosolic Ca(2+) was measured using Fura-2 and dual-wavelength microfluorimetry. The results show that CFTR is expressed in airway bronchial tissue and in cultured ASM cells. Peak Ca(2+) release in response to histamine was significantly decreased in CF cells compared with non-CF ASM cells (357 +/- 53 nM versus 558 +/- 20 nM; P < 0.001). The CFTR pharmacological blockers, glibenclamide and N-phenyl anthranilic acid, significantly reduced histamine-induced Ca(2+) release in non-CF cells, and similar results were obtained when CFTR expression was varied using antisense oligonucleotides. In conclusion, these data show that the CFTR channel is present in ASM cells, and that it modulates the release of Ca(2+) in response to contractile agents. In patients with CF, a dysfunctional CFTR channel could contribute to the asthma diathesis and gastrointestinal problems experienced by these patients.

Direct carotid puncture for endovascular thrombectomy in acute ischemic stroke.

BACKGROUND: Mechanical thrombectomy is the standard of care for acute ischemic strokes with proximal intracranial occlusion. Arterial access is commonly achieved with femoral artery puncture, although this is not always possible. In this case series, we describe 11 cases of anterior circulation stroke where direct carotid puncture was used to obtain vascular access. METHODS AND MATERIALS: A review of a prospectively maintained thrombectomy database over a 2-year period (August 2016 - August 2018) was undertaken to identify cases where direct carotid access was performed. CT and angiographic imaging were reviewed. Indications for carotid access, techniques used, technical success of procedure, recanalization rates, procedure-related complications, and patient outcomes were assessed. RESULTS: Eleven patients out of 498 overall thrombectomy procedures (2.2% thrombectomies) underwent direct carotid access. Median National Institutes of Health Stroke Scale was 20. Seventy three percent of patients received intravenous thrombolysis. The direct carotid approach was performed following the failed femoral approach due to unfavorable aortic arch anatomy, vessel tortuosity, and severe atherosclerotic disease. Direct carotid puncture was successful in 10 patients, and unsuccessful in one. Successful recanalization (TICI 2b-3) was achieved in eight patients. One patient had spontaneously recanalized on angiography. There was failed recanalization in one patient with tandem ICA and M1 occlusion. Carotid access complications included one patient with both neck hematoma and asymptomatic ICA dissection, and one of delayed central retinal artery occlusion. CONCLUSION: This case series highlights direct carotid puncture as a successful alternative when the femoral approach is not possible, allowing thrombectomy in patients who would otherwise be unsuitable.

IFN-gamma, IL-4 and IL-13 modulate responsiveness of human airway smooth muscle cells to IL-13.

BACKGROUND: IL-13 is a critical mediator of allergic asthma and associated airway hyperresponsiveness. IL-13 acts through a receptor complex comprised of IL-13Ralpha1 and IL-4Ralpha subunits with subsequent activation of signal transducer and activator of transcription 6 (STAT6). The IL-13Ralpha2 receptor may act as a decoy receptor. In human airway smooth muscle (HASM) cells, IL-13 enhances cellular proliferation, calcium responses to agonists and induces eotaxin production. We investigated the effects of pre-treatment with IL-4, IL-13 and IFN-gamma on the responses of HASM cells to IL-13. METHODS: Cultured HASM were examined for expression of IL-13 receptor subunits using polymerase chain reaction, immunofluorescence microscopy and flow cytometry. Effects of cytokine pre-treatment on IL-13-induced cell responses were assessed by looking at STAT6 phosphorylation using Western blot, eotaxin secretion and calcium responses to histamine. RESULTS: IL-13Ralpha1, IL-4Ralpha and IL-13Ralpha2 subunits were expressed on HASM cells. IL-13 induced phosphorylation of STAT6 which reached a maximum by 30 minutes. Pre-treatment with IL-4, IL-13 and, to a lesser degree, IFN-gamma reduced peak STAT6 phosphorylation in response to IL-13. IL-13, but not IFN-gamma, pre-treatment abrogated IL-13-induced eotaxin secretion. Pre-treatment with IL-4 or IL-13 abrogated IL-13-induced augmentation of the calcium transient evoked by histamine. Cytokine pre-treatment did not affect expression of IL-13Ralpha1 and IL-4Ralpha but increased expression of IL-13Ralpha2. An anti-IL-13Ralpha2 neutralizing antibody did not prevent the cytokine pre-treatment effects on STAT6 phosphorylation. Cytokine pre-treatment increased SOCS-1, but not SOCS-3, mRNA expression which was not associated with significant increases in protein expression. CONCLUSION: Pre-treatment with IL-4 and IL-13, but not IFN-gamma, induced desensitization of the HASM cells to IL-13 as measured by eotaxin secretion and calcium transients to histamine. The mechanism of IL-4 and IL-13 induced desensitization does not appear to involve either downregulation of receptor expression or induction of the IL-13Ralpha2 or the SOCS proteins.

The effect of phosphodiesterase-5 inhibitors on cerebral blood flow in humans: A systematic review.

Agents that augment cerebral blood flow (CBF) could be potential treatments for vascular cognitive impairment. Phosphodiesterase-5 inhibitors are vasodilating drugs established in the treatment of erectile dysfunction (ED) and pulmonary hypertension. We reviewed published data on the effects of phosphodiesterase-5 inhibitors on CBF in adult humans. A systematic review according to PRISMA guidelines was performed. Embase, Medline and Cochrane Library Trials databases were searched. Sixteen studies with 353 participants in total were retrieved. Studies included healthy volunteers and patients with migraine, ED, type 2 diabetes, stroke, pulmonary hypertension, Becker muscular dystrophy and subarachnoid haemorrhage. Most studies used middle cerebral artery flow velocity to estimate CBF. Few studies employed direct measurements of tissue perfusion. Resting CBF velocity was unaffected by phosphodiesterase-5 inhibitors, but cerebrovascular regulation was improved in ED, pulmonary hypertension, diabetes, Becker's and a group of healthy volunteers. This evidence suggests that phosphodiesterase-5 inhibitors improve responsiveness of the cerebral vasculature, particularly in disease states associated with an impaired endothelial dilatory response. This supports the potential therapeutic use of phosphodiesterase-5 inhibitors in vascular cognitive impairment where CBF is reduced. Further studies with better resolution of deep CBF are warranted. The review is registered on the PROSPERO database (registration number CRD42016029668).

Endovascular thrombectomy beyond 12 hours of stroke onset: a stroke network's experience of late intervention.

BACKGROUND: Selected patients with proximal anterior circulation ischemic stroke who demonstrate limited infarct and sufficient penumbra may benefit from endovascular thrombectomy (EVT) beyond conventional time limits. OBJECTIVE: To perform a retrospective review of all cases of EVT performed at our institution for proximal anterior circulation acute ischemic stroke with onset >12 hours. MATERIALS AND METHODS: Patients were assessed with non-contrast CT brain and multiphase CT angiography, with Alberta Stroke Program Early CT Score (ASPECTS) and collateral grade informing patient selection. Data, including patient demographics, workflow, neuroimaging findings, procedural details, recanalization rates, and 90-day functional outcomes, were collected. RESULTS: Of the 542 consecutive endovascular thrombectomy cases performed during the study period, 25 (4.6%) were >12 hours from stroke onset. Median age was 69 years (IQR 55-80), median National Institute of Health Stroke Scale score on presentation was 14 (IQR 11-18.5), median ASPECTS was 8 (IQR 8-9), and rate of moderate-good collateral status was 96% (n=24). Median time to groin puncture was 14 hours 40 min (IQR 12 hours 36 min - 16 hours 18 min). Rate of successful recanalization (modified Thrombolysis in Cerebral infarction 2b-3) was 88% (n=22). Rate of functional independence (90-day modified Rankin Scale score 0-2) was 52% (n=13). There were no cases of symptomatic intracranial haemorrhage and 90-day mortality rate was 12% (n=3). CONCLUSION: With the use of ASPECTS and collateral grade to guide patient selection, good functional outcome with acceptable safety parameters may be achieved in patients undergoing EVT beyond 12 hours from stroke onset.

Effect of Standard vs Intensive Blood Pressure Control on Cerebral Blood Flow in Small Vessel Disease: The PRESERVE Randomized Clinical Trial.

Importance: Blood pressure (BP) lowering is considered neuroprotective in patients with cerebral small vessel disease; however, more intensive regimens may increase cerebral hypoperfusion. This study examined the effect of standard vs intensive BP treatment on cerebral perfusion in patients with severe small vessel disease. Objective: To investigate whether standard vs intensive BP lowering over 3 months causes decreased cerebral perfusion in small vessel disease. Design, Setting, and Participants: This randomized clinical trial took place at 2 English university medical centers. Patients were randomized via a central online system (in a 1:1 ratio). Seventy patients with hypertension and with magnetic resonance imaging-confirmed symptomatic lacunar infarct and confluent white matter hyperintensities were recruited between February 29, 2012, and October 21, 2015, and randomized (36 in the standard group and 34 in the intensive group). Analyzable data were available in 62 patients, 33 in the standard group and 29 in the intensive group, for intent-to-treat analysis. This experiment examines the 3-month follow-up period. Interventions: Patients were randomized to standard (systolic, 130-140 mm Hg) or intensive (systolic, <125 mm Hg) BP targets, to be achieved through medication changes. Main Outcomes and Measures: Cerebral perfusion was measured using arterial spin labeling; the primary end point was change in global perfusion between baseline and 3 months, compared between treatment groups by analysis of variance. Linear regression compared change in perfusion against change in BP. Magnetic resonance imaging scan analysis was masked to treatment group. Results: Among 62 analyzable patients, the mean age was 69.3 years, and 60% (n = 37) were male. The mean (SD) systolic BP decreased by 8 (12) mm Hg in the standard group and by 27 (17) mm Hg in the intensive group (P < .001), with mean (SD) achieved pressures of 141 (13) and 126 (10) mm Hg, respectively. Change in global perfusion did not differ between treatment groups: the mean (SD) change was -0.5 (9.4) mL/min/100 g in the standard group vs 0.7 (8.6) mL/min/100 g in the intensive group (partial η2, 0.004; 95% CI, -3.551 to 5.818; P = .63). No differences were observed when the analysis examined gray or white matter only or was confined to those achieving target BP. The number of adverse events did not differ between treatment groups, with a mean (SD) of 0.21 (0.65) for the standard group and 0.32 (0.75) for the intensive group (P = .44). Conclusions and Relevance: Intensive BP lowering did not reduce cerebral perfusion in severe small vessel disease. Trial Registration: isrctn.org Identifier: ISRCTN37694103.

Drip and ship versus direct to endovascular thrombectomy: The impact of treatment times on transport decision-making.

INTRODUCTION: In ischaemic stroke care, fast reperfusion is essential for disability free survival. It is unknown if bypassing thrombolysis centres in favour of endovascular thrombectomy (mothership) outweighs transport to the nearest thrombolysis centre for alteplase and then transfer for endovascular thrombectomy (drip-and-ship). We use conditional probability modelling to determine the impact of treatment times on transport decision-making for acute ischaemic stroke. MATERIALS AND METHODS: Probability of good outcome was modelled using a previously published framework, data from the Irish National Stroke Register, and an endovascular thrombectomy registry at a tertiary referral centre in Ireland. Ireland was divided into 139 regions, transport times between each region and hospital were estimated using Google's Distance Matrix Application Program Interface. Results were mapped using ArcGIS 10.3. RESULTS: Using current treatment times, drip-and-ship rarely predicts best outcomes. However, if door to needle times are reduced to 30 min, drip-and-ship becomes more favourable; even more so if turnaround time (time from thrombolysis to departure for the endovascular thrombectomy centre) is also reduced. Reducing door to groin puncture times predicts better outcomes with the mothership model. DISCUSSION: This is the first case study modelling pre-hospital transport for ischaemic stroke utilising real treatment times in a defined geographic area. A moderate improvement in treatment times results in significant predicted changes to the optimisation of a national acute stroke patient transport strategy. CONCLUSIONS: Modelling patient transport for system-level planning is sensitive to treatment times at both thrombolysis and thrombectomy centres and has important implications for the future planning of thrombectomy services.

Perfusion by Arterial Spin labelling following Single dose Tadalafil In Small vessel disease (PASTIS): study protocol for a randomised controlled trial.

BACKGROUND: Cerebral small vessel disease is a common cause of vascular cognitive impairment in older people, with no licensed treatment. Cerebral blood flow is reduced in small vessel disease. Tadalafil is a widely prescribed phosphodiesterase-5 inhibitor that increases blood flow in other vascular territories. The aim of this trial is to test the hypothesis that tadalafil increases cerebral blood flow in older people with small vessel disease. METHODS/DESIGN: Perfusion by Arterial Spin labelling following Single dose Tadalafil In Small vessel disease (PASTIS) is a phase II randomised double-blind crossover trial. In two visits, 7-30 days apart, participants undergo arterial spin labelling to measure cerebral blood flow and a battery of cognitive tests, pre- and post-dosing with oral tadalafil (20 mg) or placebo. SAMPLE SIZE: 54 participants are required to detect a 15% increase in cerebral blood flow in subcortical white matter (p < 0.05, 90% power). Primary outcomes are cerebral blood flow in subcortical white matter and deep grey nuclei. Secondary outcomes are cortical grey matter cerebral blood flow and performance on cognitive tests (reaction time, information processing speed, digit span forwards and backwards, semantic fluency). DISCUSSION: Recruitment started on 4th September 2015 and 36 participants have completed to date (19th April 2017). No serious adverse events have occurred. All participants have been recruited from one centre, St George's University Hospitals NHS Foundation Trust. TRIAL REGISTRATION: European Union Clinical Trials Register: EudraCT number 2015-001235-20 . Registered on 13 May 2015.

Stroke mimic diagnoses presenting to a hyperacute stroke unit.

Stroke services have been centralised in several countries in recent years. Diagnosing acute stroke is challenging and a high proportion of patients admitted to stroke units are diagnosed as a non-stroke condition (stroke mimics). This study aims to describe the stroke mimic patient group, including their impact on stroke services. We analysed routine clinical data from 2,305 consecutive admissions to a stroke unit at St George's Hospital, London. Mimic groupings were derived from 335 individual codes into 17 groupings. From 2,305 admissions, 555 stroke mimic diagnoses were identified (24.2%) and 72% of stroke mimics had at least one stroke risk factor. Common mimic diagnoses were headache, seizure and syncope. Medically unexplained symptoms and decompensation of underlying conditions were also common. Median length of stay was 1 day; a diagnosis of dementia (p=0.028) or needing MRI (p=0.006) was associated with a longer stay. Despite emergency department assessment by specialist clinicians and computed tomography brain, one in four suspected stroke patients admitted to hospital had a non-stroke diagnosis. Stroke mimics represent a heterogeneous patient group with significant impacts on stroke services. Co-location of stroke and acute neurology services may offer advantages where service reorganisation is being considered.