20 results on '"Murphy SJX"'
Search Results
2. Vertebral body and spinal cord infarction in a pile-driver operator with fibrocartilaginous disc embolism
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Murphy, SJX, McCabe, DJH, O Donohoe, RL, and McCarthy, AJ
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- 2024
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3. Performance Metrics of the AGGRESTAR PL-12® Platelet Function Analyser in Patients with TIA or Ischaemic Stroke on Commonly-Prescribed Antiplatelet Regimens
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Ireland Amnch, Ryan Dj, Offiah C, McCabe Djh, Murphy Sjx, Collins Dr, Dermot Cox, Egan B, Dominique R. Smith, Delaney S, McCarthy Aj, and Amnch, Dublin, Ireland
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medicine.medical_specialty ,business.industry ,Internal medicine ,Ischaemic stroke ,Analyser ,Cardiology ,Medicine ,Platelet ,In patient ,business - Abstract
Introduction: The optimal time interval after venepuncture to perform platelet function/reactivity testing at low shear stress on the novel AGGRESTAR PL-12® platelet function analyser in non-Chinese Cerebrovascular Disease (CVD) patients is unknown. Methods: Twelve TIA/ischaemic stroke patients were recruited to this cross-sectional, methodological study: 3 on aspirin monotherapy, aspirindipyridamole combination therapy, clopidogrel monotherapy and aspirinclopidogrel combination therapy, respectively. The PL-12 (‘mode 2’) was used to calculate the % maximum aggregation rate to fixed doses of arachidonic acid (%MARAA) and adenosine diphosphate (%MARADP). Samples were analysed every 15 minutes from 30-135 minutes, and every 30 minutes between 165-225 minutes after venepuncture to calculate the time interval providing optimal interassay Coefficients of Variation (CVs). Results: Mean CVs were ≤ 7.37% for the %MARAA assay in patients on aspirin monotherapy or combination therapy, and ≤ 10.24% for the %MARADP assay in patients on clopidogrel monotherapy or combination therapy if assays were performed between 90-120 minutes post-venepuncture. CVs ≤ 10% were also obtained from assays performed between 90-165 minutes postvenepuncture on aspirin monotherapy or combination therapy. Discussion: Reliable and reproducible platelet function/reactivity data can be obtained with the AGGRESTAR PL-12 analyser in non-Chinese CVD patients on commonly-prescribed antiplatelet monotherapy or combination therapy regimens between 90-120 minutes post-venepuncture.
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- 2021
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4. Profile of reticulated platelets in the early, subacute and late phases after transient ischemic attack or ischemic stroke
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Lim, ST, primary, Tobin, WO, additional, Murphy, SJX, additional, Kinsella, JA, additional, Smith, DR, additional, Lim, SY, additional, Murphy, SM, additional, Coughlan, T, additional, Collins, DR, additional, O’Neill, D, additional, Egan, B, additional, Tierney, S, additional, and McCabe, DJH, additional
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- 2020
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5. Platelet function/reactivity testing and prediction of risk of recurrent vascular events and outcomes after TIA or ischaemic stroke: systematic review and meta-analysis
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Lim, ST, Thijs, V, Murphy, SJX, Fernandez-Cadenas, I, Montaner, J, Offiah, C, Marquardt, L, Kelly, PJ, Bath, PM, Lim, SY, Ford, GA, Norrving, B, Cox, D, Prodan, CI, Barber, PA, Werring, DJ, Perry, R, Zgaga, L, Dawson, J, and McCabe, DJH
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Meta-analysis ,Transient ischaemic attack ,on-treatment platelet reactivity ,Systematic review ,Platelet function ,cardiovascular diseases ,Ischaemic stroke - Abstract
Background The prevalence of ex vivo 'high on-treatment platelet reactivity (HTPR)' and its relationship with recurrent vascular events/outcomes in patients with ischaemic cerebrovascular disease (CVD) is unclear. Methods A systematic review and meta-analysis was performed in accordance with the PRISMA statement. MEDLINE, EMBASE and Cochrane Library were searched for completed manuscripts until May 2019 on TIA/ischaemic stroke patients, >= 18 years, treated with commonly-prescribed antiplatelet therapy, who had platelet function/reactivity testing and prospective follow-up data on recurrent stroke/TIA, myocardial infarction, vascular death or other cerebrovascular outcomes. Data were pooled using random-effects meta-analysis. Primary outcome was the composite risk of recurrent stroke/TIA, myocardial infarction or vascular death. Secondary outcomes were recurrent stroke/TIA, severe stroke (NIHSS > 16) or disability/impairment (modified Rankin scale >= 3) during follow-up. Results Antiplatelet-HTPR prevalence was 3-65% with aspirin, 8-56% with clopidogrel and 1.8-35% with aspirin-clopidogrel therapy. Twenty studies (4989 patients) were included in our meta-analysis. There was a higher risk of the composite primary outcome (OR 2.93, 95% CI 1.90-4.51) and recurrent ischaemic stroke/TIA (OR 2.43, 95% CI 1.51-3.91) in patients with vs. those without 'antiplatelet-HTPR' on any antiplatelet regimen. These risks were also more than twofold higher in patients with vs. those without 'aspirin-HTPR' and 'dual antiplatelet-HTPR', respectively. Clopidogrel-HTPR status did not significantly predict outcomes, but the number of eligible studies was small. The risk of severe stroke was higher in those with vs. without antiplatelet-HTPR (OR 2.65, 95% CI 1.00-7.01). Discussion Antiplatelet-HTPR may predict risks of recurrent vascular events/outcomes in CVD patients. Given the heterogeneity between studies, further prospective, multi-centre studies are warranted.
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- 2020
6. Profile of reticulated platelets in the early, subacute and late phases after transient ischemic attack or ischemic stroke.
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Lim, ST, Tobin, WO, Murphy, SJX, Kinsella, JA, Smith, DR, Lim, SY, Murphy, SM, Coughlan, T, Collins, DR, O'Neill, D, Egan, B, Tierney, S, and McCabe, DJH
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TRANSIENT ischemic attack ,LACUNAR stroke ,ISCHEMIC stroke ,BLOOD platelets ,CEREBROVASCULAR disease ,BLOOD flow ,MEAN platelet volume - Abstract
Information regarding the profile of reticulated platelets (RP) in ischemic cerebrovascular disease (CVD) patients is limited. Data from two prospective, observational, case-control studies were combined to compare the %RP using whole blood flow cytometry in patients ≤ 4 weeks of TIA/stroke onset (baseline, N = 210), and 14 ±7 days (14d, N = 182) and ≥ 90 days (90d, N = 145) after starting or changing antiplatelet therapy with healthy controls (N = 34). There were no differences in median %RP between the overall CVD patient population at baseline or 14d vs. controls (P ≥ 0.2). However, the median %RP was significantly higher in CVD patients overall at 90d (P =.036), and in the subgroup of patients with "lacunar" TIA/ischemic stroke at baseline (P =.04) and at 90d (P =.01), but not at 14d (P =.06) vs. controls. There were no significant differences in the median %RP between other TIA/stroke subgroups and controls (P ≥ 0.05). Elevated circulating reticulated platelets, as a marker of increased platelet production/turnover, may occur following an ischemic event in a well-phenotyped TIA/ischemic stroke population overall, but may precede symptom onset at least in the subgroup with small vessel occlusion. These data improve our understanding of the profile of reticulated platelets in CVD patients. [ABSTRACT FROM AUTHOR]
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- 2022
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7. von Willebrand factor antigen, von Willebrand factor propeptide and ADAMTS13 activity in TIA or ischaemic stroke patients changing antiplatelet therapy.
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Smith DR, Lim ST, Murphy SJX, Hickey FB, Offiah C, Murphy SM, Collins DR, Coughlan T, O'Neill D, Egan B, O'Donnell JS, O'Sullivan JM, and McCabe DJH
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- Humans, Male, Female, Aged, Middle Aged, Pilot Projects, Clopidogrel therapeutic use, Protein Precursors, von Willebrand Factor metabolism, ADAMTS13 Protein blood, Platelet Aggregation Inhibitors therapeutic use, Ischemic Attack, Transient blood, Ischemic Attack, Transient drug therapy, Ischemic Stroke blood, Ischemic Stroke drug therapy
- Abstract
Data are limited on the impact of commencing antiplatelet therapy on von Willebrand Factor Antigen (VWF:Ag) or von Willebrand Factor propeptide (VWFpp) levels and ADAMTS13 activity, and their relationship with platelet reactivity following TIA/ischaemic stroke. In this pilot, observational study, VWF:Ag and VWFpp levels and ADAMTS13 activity were quantified in 48 patients ≤4 weeks of TIA/ischaemic stroke (baseline), and 14 days (14d) and 90 days (90d) after commencing aspirin, clopidogrel or aspirin+dipyridamole. Platelet reactivity was assessed at moderately-high shear stress (PFA-100® Collagen-Epinephrine / Collagen-ADP / INNOVANCE PFA P2Y assays), and low shear stress (VerifyNow® Aspirin / P2Y12, and Multiplate® Aspirin / ADP assays). VWF:Ag levels decreased and VWFpp/VWF:Ag ratio increased between baseline and 14d and 90d in the overall population (P ≤ 0.03). In the clopidogrel subgroup, VWF:Ag levels decreased and VWFpp/VWF:Ag ratio increased between baseline and 14d and 90d (P ≤ 0.01), with an increase in ADAMTS13 activity between baseline vs. 90d (P ≤ 0.03). In the aspirin+dipyridamole subgroup, there was an inverse relationship between VWF:Ag and VWFpp levels with both PFA-100 C-ADP and INNOVANCE PFA P2Y closure times (CTs) at baseline (P ≤ 0.02), with PFA-100 C-ADP, INNOVANCE PFA P2Y and C-EPI CTs at 14d (P ≤ 0.05), and between VWF:Ag levels and PFA-100 INNOVANCE PFA P2Y CTs at 90d (P = 0.03). There was a positive relationship between ADAMTS13 activity and PFA-100 C-ADP CTs at baseline (R
2 = 0.254; P = 0.04). Commencing/altering antiplatelet therapy, mainly attributed to commencing clopidogrel in this study, was associated with decreasing endothelial activation following TIA/ischaemic stroke. These data enhance our understanding of the impact of VWF:Ag and VWFpp especially on ex-vivo platelet reactivity status at high shear stress after TIA/ischaemic stroke., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)- Published
- 2024
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8. Prolonged Benign Episodic Unilateral Mydriasis in Hemiplegic Migraine.
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Murphy SJX, Francis I, and Nadarajan V
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- Humans, Hemiplegia, Mydriasis diagnosis, Migraine with Aura complications, Migraine with Aura diagnosis, Migraine Disorders complications, Migraine Disorders diagnosis
- Abstract
Competing Interests: The authors report no conflicts of interest.
- Published
- 2024
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9. Correction to: Frequency of inter‑specialty consensus decisions and adherence to advice following discussion at a weekly neurovascular multidisciplinary meeting.
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Offiah C, Tierney S, Egan B, Collins RD, Ryan DJ, McCarthy AJ, Smith DR, Mahon J, Boyle E, Delaney H, O 'Donohoe R, Hurley A, Walsh RA, Murphy SM, Bogdanova-Mihaylova P, O 'Dowd S, Kelly MJ, Omer T, Coughlan T, O'Neill D, Martin M, Murphy SJX, and McCabe DJH
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- 2024
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10. Frequency of inter-specialty consensus decisions and adherence to advice following discussion at a weekly neurovascular multidisciplinary meeting.
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Offiah C, Tierney S, Egan B, Collins RD, Ryan DJ, McCarthy AJ, Smith DR, Mahon J, Boyle E, Delaney H, O 'Donohoe R, Hurley A, Walsh RA, Murphy SM, Bogdanova-Mihaylova P, O 'Dowd S, Kelly MJ, Omer T, Coughlan T, O'Neill D, Martin M, Murphy SJX, and McCabe DJH
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- Humans, Constriction, Pathologic etiology, Consensus, Treatment Outcome, Risk Factors, Carotid Stenosis surgery, Stroke prevention & control, Endarterectomy, Carotid, Brain Ischemia
- Abstract
Background/aims: Data are limited on the frequency of 'consensus decisions' between sub-specialists attending a neurovascular multidisciplinary meeting (MDM) regarding management of patients with extracranial carotid/vertebral stenoses and post-MDM 'adherence' to such advice., Methods: This prospective audit/quality improvement project collated prospectively-recorded data from a weekly Neurovascular/Stroke Centre MDM documenting the proportion of extracranial carotid/vertebral stenosis patients in whom 'consensus management decisions' were reached by neurologists, vascular surgeons, stroke physicians-geriatricians and neuroradiologists. Adherence to MDM advice was analysed in asymptomatic carotid stenosis (ACS), symptomatic carotid stenosis (SCS), 'indeterminate symptomatic status stenosis' (ISS) and vertebral artery stenosis (VAS) patients, including intervals between index event to MDM + / - intervention., Results: One hundred fifteen patients were discussed: 108 with carotid stenosis and 7 with VAS. Consensus regarding management was noted in 96.5% (111/115): 100% with ACS and VAS, 96.2% with SCS and 92.9% with ISS. Adherence to MDM management advice was 96.4% (107/111): 100% in ACS, ISS and VAS patients; 92% (46/50) in SCS patients. The median interval from index symptoms to revascularisation in 50-99% SCS patients was 12.5 days (IQR: 9-18.3 days; N = 26), with a median interval from MDM to revascularisation of 5.5 days (IQR: 1-7 days). Thirty patients underwent revascularisation. Two out of twenty-nine patients (6.9%) with either SCS or ISS had a peri-procedural ipsilateral ischaemic stroke, with no further strokes/deaths during 3-months follow-up., Conclusions: The high frequency of inter-specialty consensus regarding management and adherence to proposed treatment supports a collaborative/multidisciplinary model of care in patients with extracranial arterial stenoses. Service development should aim to shorten times between MDM discussion-intervention and optimise prevention of stroke/death., (© 2023. The Author(s).)
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- 2023
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11. Assessment of on-treatment platelet reactivity at high and low shear stress and platelet activation status after the addition of dipyridamole to aspirin in the early and late phases after TIA and ischaemic stroke.
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Lim ST, Murphy SJX, Murphy SM, Coughlan T, O'Neill D, Tierney S, Egan B, Collins DR, McCarthy AJ, Lim SY, Smith DR, Cox D, and McCabe DJH
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- Adenosine Diphosphate metabolism, Adenosine Diphosphate pharmacology, Aspirin pharmacology, Aspirin therapeutic use, Blood Platelets, Dipyridamole metabolism, Dipyridamole pharmacology, Dipyridamole therapeutic use, Humans, Platelet Activation, Platelet Aggregation Inhibitors pharmacology, Platelet Aggregation Inhibitors therapeutic use, Prospective Studies, Brain Ischemia metabolism, Ischemic Attack, Transient drug therapy, Ischemic Stroke, Stroke
- Abstract
Background: Data are limited on the ability of dipyridamole to additionally inhibit platelet function/reactivity in ischaemic cerebrovascular disease (CVD) patients on aspirin., Aims: To assess inhibition of platelet function/reactivity and platelet activation with dipyridamole in CVD., Methods: This prospective, observational study assessed TIA/ischaemic stroke patients before (baseline; N = 60), at 14 ±7 days (14d, N = 39) and ≥ 90 days (90d, N = 31) after adding dipyridamole to aspirin. Platelet function/reactivity at high shear stress (PFA-100® C-ADP) and low shear stress (VerifyNow® P2Y12 and Multiplate® ADP assays), and platelet activation status (% expression of CD62P, CD63 and leucocyte-platelet complexes on whole blood flow cytometry) were quantified. 'Dipyridamole-high on-treatment platelet reactivity (HTPR)' was defined as failure to inhibit ADP-induced platelet aggregation +/- adhesion compared with the patient's baseline on aspirin monotherapy by more than twice the coefficient-of-variation of the assay after adding dipyridamole to aspirin., Results: Dipyridamole-HTPR was identified in 71.4-75% of patients on PFA-100 C-ADP, 83.9-86.8% of patients on VerifyNow P2Y12, and 81.5-83.3% of patients on Multiplate ADP assays. There were no changes in CD62P/CD63 expression (P ≥ 0.18), or consistent changes in leucocyte-platelet complexes in CVD patients overall at 14d or 90d vs. baseline after commencing dipyridamole. Monocyte-platelet complexes increased in the patient subgroup with dipyridamole-HTPR at 14d and 90d on PFA-100, and at 14d on VerifyNow (P ≤ 0.04), but not in those without dipyridamole-HTPR., Discussion: Additional antiplatelet effects of dipyridamole are detectable under high and low shear stress conditions with user-friendly platelet function/reactivity tests ex vivo. Increasing circulating monocyte-platelet complexes over time are associated with dipyridamole-HTPR., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2022
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12. Platelet Biomarkers in Patients with Atherosclerotic Extracranial Carotid Artery Stenosis: A Systematic Review.
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Subramanian A, Delaney S, Murphy SJX, Smith DR, Offiah C, McMahon J, de Borst GJ, Naylor AR, Hamilton G, Kinsella JA, and McCabe DJH
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- Aspirin therapeutic use, Biomarkers, Blood Platelets, Humans, Platelet Aggregation Inhibitors therapeutic use, Carotid Stenosis complications, Carotid Stenosis diagnostic imaging, Carotid Stenosis drug therapy, Stroke etiology
- Abstract
Objective: The aim was to enhance understanding of the role of platelet biomarkers in the pathogenesis of vascular events and risk stratifying patients with asymptomatic or symptomatic atherosclerotic carotid stenosis., Data Sources: Systematic review conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement., Review Methods: A systematic review collated data from 1975 to 2020 on ex vivo platelet activation and platelet function/reactivity in patients with atherosclerotic carotid stenosis., Results: Forty-three studies met the inclusion criteria; the majority included patients on antiplatelet therapy. Five studies showed increased platelet biomarkers in patients with ≥ 30% asymptomatic carotid stenosis (ACS) vs. controls, with one neutral study. Preliminary data from one study suggested that quantification of "coated platelets" in combination with stenosis severity may aid risk stratification in patients with ≥ 50% - 99% ACS. Platelets were excessively activated in patients with ≥ 30% symptomatic carotid stenosis (SCS) vs. controls (≥ 11 positive studies and one neutral study). Antiplatelet-High on Treatment Platelet Reactivity (HTPR), previously called "antiplatelet resistance", was observed in 23% - 57% of patients on aspirin, with clopidogrel-HTPR in 25% - 100% of patients with ≥ 50% - 99% ACS. Aspirin-HTPR was noted in 9.5% - 64% and clopidogrel-HTPR in 0 - 83% of patients with ≥ 50% SCS. However, the data do not currently support the use of ex vivo platelet function/reactivity testing to tailor antiplatelet therapy outside of a research setting. Platelets are excessively activated (n = 5), with increased platelet counts (n = 3) in recently symptomatic vs. asymptomatic patients, including those without micro-emboli on transcranial Doppler (TCD) monitoring (n = 2). Most available studies (n = 7) showed that platelets become more reactive or activated following carotid endarterectomy or stenting, either as an acute phase response to intervention or peri-procedural treatment., Conclusion: Platelets are excessively activated in patients with carotid stenosis vs. controls, in recently symptomatic vs. asymptomatic patients, and may become activated/hyper-reactive following carotid interventions despite commonly prescribed antiplatelet regimens. Further prospective multicentre studies are required to determine whether models combining clinical, neurovascular imaging, and platelet biomarker data can facilitate optimised antiplatelet therapy in individual patients with carotid stenosis., (Copyright © 2021 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.)
- Published
- 2022
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13. von Willebrand Factor Antigen, von Willebrand Factor Propeptide, and ADAMTS13 in Carotid Stenosis and Their Relationship with Cerebral Microemboli.
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Murphy SJX, Lim ST, Hickey F, Kinsella JA, Smith DR, Tierney S, Egan B, Feeley TM, Murphy SM, Collins DR, Coughlan T, O'Neill D, Harbison JA, Madhavan P, O'Neill SM, Colgan MP, O'Donnell JS, O'Sullivan JM, Hamilton G, and McCabe DJH
- Subjects
- ADAMTS13 Protein blood, Aged, Carotid Stenosis blood, Carotid Stenosis complications, Female, Humans, Intracranial Embolism blood, Intracranial Embolism etiology, Male, Middle Aged, Prospective Studies, von Willebrand Factor analysis, ADAMTS13 Protein metabolism, Carotid Stenosis metabolism, Intracranial Embolism metabolism, von Willebrand Factor metabolism
- Abstract
Background: The relationship between von Willebrand factor antigen (VWF:Ag), VWF propeptide (VWFpp), VWFpp/VWF:Ag ratio, ADAMTS13 activity, and microembolic signal (MES) status in carotid stenosis is unknown., Methods: This prospective, multicenter study simultaneously assessed plasma VWF:Ag levels, VWFpp levels and ADAMTS13 activity, and their relationship with MES in asymptomatic versus symptomatic moderate-to-severe (≥50-99%) carotid stenosis patients. One-hour transcranial Doppler ultrasound of the middle cerebral arteries classified patients as MES+ve or MES-ve., Results: Data from 34 asymptomatic patients were compared with 43 symptomatic patients in the "early phase" (≤4 weeks) and 37 patients in the "late phase" (≥3 months) after transient ischemic attack (TIA)/ischemic stroke. VWF:Ag levels were higher ( p = 0.049) and VWFpp/VWF:Ag ratios lower ( p = 0.006) in early symptomatic than in asymptomatic patients overall, and in early symptomatic versus asymptomatic MES-ve subgroups ( p ≤0.02). There were no intergroup differences in VWFpp expression or ADAMTS13 activity ( p ≥0.05). VWF:Ag levels and ADAMTS13 activity decreased ( p ≤ 0.048) and VWFpp/VWF:Ag ratios increased ( p = 0.03) in symptomatic patients followed up from the early to late phases after TIA/stroke. Although there were no differences in the proportions of symptomatic and asymptomatic patients with blood group O, a combined analysis of early symptomatic and asymptomatic patients revealed lower median VWF:Ag levels in patients with blood group O versus those without blood group O (9.59 vs. 12.32 µg/mL, p = 0.035)., Discussion: VWF:Ag expression, a marker of endothelial ± platelet activation, is enhanced in recently symptomatic versus asymptomatic carotid stenosis patients, including in MES-ve patients, and decreases with ADAMTS13 activity over time following atherosclerotic TIA/ischemic stroke., Competing Interests: S.J.X.M. reports grants from Trinity College Dublin Innovation Bursary, Meath Foundation, Joint IICN/Merck Serono Fellowship in Neuroscience, The Vascular Neurology Research Foundation, unrestricted educational grant from Bayer HealthCare Ireland, and unrestricted educational grant from Verum Diagnostica, GmbH, outside the submitted work.S.T.L. reports grants from Meath Foundation, the Irish Institute of Clinical Neuroscience (IICN)/Novartis Ireland Fellowship Grant, the Irish Heart Foundation Stroke Prevention Bursary, the Vascular Neurology Research Foundation, Ireland, and unrestricted educational grant funding from Biogen Idec Ireland, outside the submitted work.D.J.H.M. reports grants from the Trinity College Dublin Innovation Bursary, Trinity College Dublin, Ireland, the Meath Foundation, Ireland, Joint IICN/Merck Serono Fellowship in Neuroscience, the Vascular Neurology Research Foundation, Bayer HealthCare Ireland, Verum Diagnostica, GmbH, the Irish Institute of Clinical Neuroscience (IICN)/Novartis Ireland Fellowship Grant, the Irish Heart Foundation Stroke Prevention Bursary, and Biogen Idec Ireland, during the conduct of the study., (Thieme. All rights reserved.)
- Published
- 2021
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14. Platelet function/reactivity testing and prediction of risk of recurrent vascular events and outcomes after TIA or ischaemic stroke: systematic review and meta-analysis.
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Lim ST, Thijs V, Murphy SJX, Fernandez-Cadenas I, Montaner J, Offiah C, Marquardt L, Kelly PJ, Bath PM, Lim SY, Ford GA, Norrving B, Cox D, Prodan CI, Barber PA, Werring DJ, Perry R, Zgaga L, Dawson J, and McCabe DJH
- Subjects
- Humans, Platelet Aggregation Inhibitors therapeutic use, Brain Ischemia complications, Brain Ischemia drug therapy, Brain Ischemia epidemiology, Ischemic Attack, Transient epidemiology, Ischemic Stroke, Stroke drug therapy, Stroke epidemiology
- Abstract
Background: The prevalence of ex vivo 'high on-treatment platelet reactivity (HTPR)' and its relationship with recurrent vascular events/outcomes in patients with ischaemic cerebrovascular disease (CVD) is unclear., Methods: A systematic review and meta-analysis was performed in accordance with the PRISMA statement. MEDLINE, EMBASE and Cochrane Library were searched for completed manuscripts until May 2019 on TIA/ischaemic stroke patients, ≥ 18 years, treated with commonly-prescribed antiplatelet therapy, who had platelet function/reactivity testing and prospective follow-up data on recurrent stroke/TIA, myocardial infarction, vascular death or other cerebrovascular outcomes. Data were pooled using random-effects meta-analysis. Primary outcome was the composite risk of recurrent stroke/TIA, myocardial infarction or vascular death. Secondary outcomes were recurrent stroke/TIA, severe stroke (NIHSS > 16) or disability/impairment (modified Rankin scale ≥ 3) during follow-up., Results: Antiplatelet-HTPR prevalence was 3-65% with aspirin, 8-56% with clopidogrel and 1.8-35% with aspirin-clopidogrel therapy. Twenty studies (4989 patients) were included in our meta-analysis. There was a higher risk of the composite primary outcome (OR 2.93, 95% CI 1.90-4.51) and recurrent ischaemic stroke/TIA (OR 2.43, 95% CI 1.51-3.91) in patients with vs. those without 'antiplatelet-HTPR' on any antiplatelet regimen. These risks were also more than twofold higher in patients with vs. those without 'aspirin-HTPR' and 'dual antiplatelet-HTPR', respectively. Clopidogrel-HTPR status did not significantly predict outcomes, but the number of eligible studies was small. The risk of severe stroke was higher in those with vs. without antiplatelet-HTPR (OR 2.65, 95% CI 1.00-7.01)., Discussion: Antiplatelet-HTPR may predict risks of recurrent vascular events/outcomes in CVD patients. Given the heterogeneity between studies, further prospective, multi-centre studies are warranted.
- Published
- 2020
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15. Relationship between 'on-treatment platelet reactivity', shear stress, and micro-embolic signals in asymptomatic and symptomatic carotid stenosis.
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Murphy SJX, Lim ST, Kinsella JA, Tierney S, Egan B, Feeley TM, Murphy SM, Walsh RA, Collins DR, Coughlan T, O'Neill D, Harbison JA, Madhavan P, O'Neill SM, Colgan MP, Cox D, Moran N, Hamilton G, Meaney JF, and McCabe DJH
- Subjects
- Aged, Aspirin administration & dosage, Brain Ischemia drug therapy, Carotid Stenosis diagnostic imaging, Female, Humans, Intracranial Embolism diagnostic imaging, Male, Middle Aged, Middle Cerebral Artery diagnostic imaging, Platelet Aggregation Inhibitors administration & dosage, Prospective Studies, Stroke drug therapy, Ultrasonography, Doppler, Transcranial, Aspirin pharmacology, Blood Platelets drug effects, Blood Platelets physiology, Carotid Stenosis drug therapy, Intracranial Embolism drug therapy, Platelet Aggregation Inhibitors pharmacology
- Abstract
Background: Assessment of 'high on-treatment platelet reactivity (HTPR)' could enhance understanding of the pathophysiology of first or recurrent vascular events in carotid stenosis patients on antiplatelet therapy., Methods: This prospective, multi-centre study assessed antiplatelet-HTPR status and its relationship with micro-emboli signals (MES) in asymptomatic vs. symptomatic ≥ 50-99% carotid stenosis. Platelet function/reactivity was assessed under 'moderately high shear stress' with the PFA-100
® and 'low shear stress' with VerifyNow® and Multiplate® analysers. Bilateral 1-h transcranial Doppler ultrasound of the middle cerebral arteries classified patients as MES + ve or MES - ve., Results: Data from 34 asymptomatic patients were compared with 43 symptomatic patients in the 'early phase' (≤ 4 weeks) and 37 patients in the 'late phase' (≥ 3 months) after TIA/ischaemic stroke. Median daily aspirin doses were higher in early symptomatic (225 mg; P < 0.001), but not late symptomatic (75 mg; P = 0.62) vs. asymptomatic patients (75 mg). There was a lower prevalence of aspirin-HTPR in early (28.6%; P = 0.028), but not late symptomatic (38.9%; P = 0.22) compared with asymptomatic patients (56.7%) on the PFA-100® , but not on the VerifyNow® or Multiplate® (P ≤ 0.53). Early symptomatic patients had a higher prevalence of aspirin-HTPR on the PFA-100® (28.6%) vs. VerifyNow® (9.5%; P = 0.049), but not Multiplate® assays (11.9%, P = 0.10). There was no difference in aspirin-HTPR prevalence between any symptomatic vs. asymptomatic MES + ve or MES - ve subgroup., Discussion: Recently symptomatic moderate-severe carotid stenosis patients had a lower prevalence of aspirin-HTPR than their asymptomatic counterparts on the PFA-100® , likely related to higher aspirin doses. The prevalence of antiplatelet-HTPR was positively influenced by higher shear stress levels, but not MES status.- Published
- 2020
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16. Increased Leucocyte-Platelet Complex Formation in Recently Symptomatic versus Asymptomatic Carotid Stenosis Patients and in Micro-emboli Negative Subgroups.
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Murphy SJX, Lim ST, Kinsella JA, Tierney S, Egan B, Feeley TM, Murphy SM, Walsh RA, Collins DR, Coughlan T, O'Neill D, Harbison JA, Madhavan P, O'Neill SM, Colgan MP, Cox D, Moran N, Hamilton G, and McCabe DJH
- Subjects
- Aged, Asymptomatic Diseases, Cell Communication, Disease Progression, Female, Humans, Male, Middle Aged, Platelet Activation, Prognosis, Prospective Studies, Blood Platelets physiology, Carotid Stenosis diagnosis, Intracranial Embolism diagnosis, Leukocytes physiology
- Abstract
Introduction: Cerebral micro-embolic signals (MES) predict risk of stroke in carotid stenosis patients. However, MES-negative 'recently symptomatic patients' also have a higher stroke risk than 'asymptomatic patients'. Differences in platelet activation status may contribute to this disparity in risk., Methods: This prospective, observational study assessed platelet biomarkers and their relationship with MES in asymptomatic versus symptomatic moderate (≥50-69%) or severe (≥70-99%) carotid stenosis patients. Full blood count parameters were measured and whole-blood flow cytometry was used to quantify platelet surface CD62P and CD63 expression and leucocyte-platelet complex formation. Bilateral simultaneous transcranial Doppler ultrasound of the middle cerebral arteries classified patients as 'MES positive' or 'MES negative'., Results: Data from 34 asymptomatic patients were compared with those from 43 symptomatic patients in the 'early phase' (≤ 4 weeks) and 37 of these symptomatic patients in the 'late phase' (≥ 3 months) after transient ischaemic attack/ischaemic stroke. There were no differences in %CD62P or %CD63 expression between early or late symptomatic and asymptomatic patients overall ( p > 0.05). The percentage of lymphocyte-platelet complexes was higher in early symptomatic than in asymptomatic patients (2.8 vs. 2.16%; p < 0.001). MES were more commonly observed in early symptomatic (31.4%; p = 0.027) but not in late symptomatic (6.7%; p = 0.996) versus asymptomatic patients (7.1%). The percentage of lymphocyte-platelet complexes was higher in early symptomatic than in asymptomatic MES-negative patients (2.7 vs. 2.17%; p = 0.02)., Conclusion: These data add to the evidence that leucocyte-platelet complex formation/platelet activation is increased in recently symptomatic versus asymptomatic patients, and may contribute to the pathogenesis of first and subsequent strokes in carotid stenosis patients, including those who are MES negative., Competing Interests: None declared., (Georg Thieme Verlag KG Stuttgart · New York.)
- Published
- 2019
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17. Optimal Antiplatelet Therapy in Moderate to Severe Asymptomatic and Symptomatic Carotid Stenosis: A Comprehensive Review of the Literature.
- Author
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Murphy SJX, Naylor AR, Ricco JB, Sillesen H, Kakkos S, Halliday A, de Borst GJ, Vega de Ceniga M, Hamilton G, and McCabe DJH
- Subjects
- Aspirin therapeutic use, Asymptomatic Diseases therapy, Carotid Stenosis surgery, Clopidogrel therapeutic use, Dipyridamole therapeutic use, Drug Therapy, Combination, Endarterectomy, Carotid, Endovascular Procedures, Humans, Recurrence, Carotid Stenosis drug therapy, Platelet Aggregation Inhibitors therapeutic use, Stroke prevention & control
- Abstract
Objectives: Carotid stenosis patients are at risk of vascular events despite antiplatelet therapy. Data on prescribed antiplatelet regimens have not been comprehensively collated from trials to guide optimal therapy in this population., Methods: This review was conducted in line with the current Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Medline, Ovid, Embase, Web of Science, and Google Scholar from 1988 to 2018 were searched using the search terms "carotid stenosis", "asymptomatic", "symptomatic", "antiplatelet", and "anti-platelet" to identify randomised trials in patients with asymptomatic or symptomatic extracranial moderate-severe carotid stenosis on any form of antiplatelet therapy in which vascular events and pre specified composite outcome events were reported., Results: Twenty-five studies were judged eligible for inclusion. Data from one randomised controlled trial showed no significant difference in benefit with aspirin versus placebo in asymptomatic carotid stenosis, but it is still reasonable to recommend aspirin (81-325 mg daily) for prevention of vascular events in these patients. Low to medium dose aspirin (81-325 mg daily) is superior to higher doses (>650 mg daily) at preventing recurrent vascular events in patients undergoing endarterectomy. Data from endovascular treatment (EVT) trials support peri-procedural treatment of asymptomatic and symptomatic patients with 81-325 mg of aspirin daily. The use of peri-procedural aspirin-clopidogrel in patients undergoing EVT is based on one pilot trial, but appears safe. Short-term aspirin-dipyridamole or aspirin-clopidogrel treatments are equally effective at reducing micro-embolic signals on transcranial Doppler ultrasound in patients with ≥50% symptomatic carotid stenosis. There is insufficient evidence to recommend routine aspirin-clopidogrel combination therapy to reduce the risk of recurrent clinical ischaemic events in patients with symptomatic moderate-severe carotid stenosis., Conclusions: This comprehensive review outlines an evidence based approach to antiplatelet therapy in carotid stenosis patients. Future trials should randomise such patients to receive different antiplatelet regimens to assess their efficacy and safety and to optimise peri-procedural and long-term preventive treatment in this patient cohort., (Copyright © 2018 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.)
- Published
- 2019
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18. Extracranial and Intracranial Vasculopathy With "Moyamoya Phenomenon" in Association With Alagille Syndrome.
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Delaney S, O'Connor G, Reardon W, Murphy SJX, Tierney S, Ryan BM, Delaney H, Doherty CP, Guiney M, Brennan P, Tobin WO, and McCabe DJH
- Abstract
Background: Alagille syndrome (AGS) is an autosomal-dominant, multisystem disorder caused by mutations in the JAG1 gene. Case Description: A 34-year-old man was referred to our service 10 years ago with focal seizures with impaired awareness and transient slurred speech. He had a 5-year history of intermittent left monocular low-flow retinopathy. He has a family history of AGS. General examination revealed mild hypertension, aortic regurgitation, and livedo reticularis. Neurological examination was normal. Investigations: He had mild hyperlipidaemia and persistently-positive lupus anticoagulant consistent with primary anti-phospholipid syndrome. Color Doppler ultrasound revealed low velocity flow in a narrowed extracranial left internal carotid artery (ICA). MR and CT angiography revealed a diffusely narrowed extracranial and intracranial left ICA. Formal cerebral angiography confirmed severe left ICA narrowing consistent with a left ICA "vasculopathy" and moyamoya phenomenon. Transthoracic echocardiogram revealed a bicuspid aortic valve and aortic incompetence. Molecular genetic analysis identified a missense mutation (A211P) in exon 4 of the JAG1 gene, consistent with AGS. Discussion: AGS should be considered in young adults with TIAs/stroke and unexplained extracranial or intracranial vascular abnormalities, and/or moyamoya phenomenon, even in the absence of other typical phenotypic features. Gene panels should include JAG1 gene testing in similar patients.
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- 2019
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19. Increased platelet count and reticulated platelets in recently symptomatic versus asymptomatic carotid artery stenosis and in cerebral microembolic signal-negative patient subgroups: results from the HaEmostasis In carotid STenosis (HEIST) study.
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Murphy SJX, Lim ST, Kinsella JA, Murphy D, Enright HM, and McCabe DJH
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- Aged, Automation, Laboratory, Carotid Stenosis drug therapy, Female, Flow Cytometry, Follow-Up Studies, Humans, Longitudinal Studies, Male, Platelet Aggregation Inhibitors therapeutic use, Platelet Count, Prospective Studies, Severity of Illness Index, Blood Platelets, Carotid Stenosis blood
- Abstract
Background: The pathophysiological mechanisms responsible for the disparity in stroke risk between asymptomatic and symptomatic carotid stenosis patients are not fully understood. The functionally important reticulated platelet fraction and reticulocytes could play a role., Objectives: We performed a prospective, multi-centre, observational analytical study comparing full blood count parameters and platelet production/turnover/activation markers in patients with asymptomatic versus recently symptomatic moderate (≥ 50-69%) or severe (≥ 70-99%) carotid stenosis., Patients/methods: Data from 34 asymptomatic patients were compared with 43 symptomatic patients in the 'early phase' (≤ 4 weeks) and 37 of these patients in the 'late phase' (≥ 3 months) after TIA/ischaemic stroke. Reticulated platelets were quantified by whole blood flow cytometry and reticulated platelets and red cell reticulocytes by 'automated assays' (Sysmex XE-2100™). Bilateral simultaneous transcranial Doppler ultrasound monitoring classified patients as micro-embolic signal (MES)+ve or MES-ve., Results: Mean platelet count was higher in early (216 × 10
9 /L; P = 0.04) and late symptomatic (219 × 109 /L; P = 0.044) than asymptomatic patients (194 × 109 /L). Mean platelet volume was higher in early symptomatic than asymptomatic patients (10.8 vs. 10.45 fl; P = 0.045). Automated assays revealed higher % reticulated platelet fractions in early (5.78%; P < 0.001) and late symptomatic (5.11%; P = 0.01) than asymptomatic patients (3.48%). Red cell reticulocyte counts were lower in early (0.92%; P = 0.035) and late symptomatic (0.93%; P = 0.036) than asymptomatic patients (1.07%). The automated % reticulated platelet fraction was also higher in early symptomatic than asymptomatic MES-ve patients (5.7 vs. 3.55%; P = 0.001)., Discussion: The combination of increased platelet counts and a shift towards production of an increased population of larger, young, reticulated platelets could contribute to a higher risk of first or recurrent cerebrovascular events in recently symptomatic versus asymptomatic carotid stenosis, including those who are MES-ve.- Published
- 2018
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20. Clinical outcomes and a high prevalence of abnormalities on comprehensive arterial and venous thrombophilia screening in TIA or ischaemic stroke patients with a patent foramen ovale, an inter-atrial septal aneurysm or both.
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Lim ST, Murphy SJX, Smith DR, Williams J, Navarro SG, McCabe J, Moore DP, McHugh J, and McCabe DJH
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- Adult, Aged, Echocardiography, Female, Fibrinolytic Agents therapeutic use, Foramen Ovale, Patent therapy, Humans, Ischemic Attack, Transient therapy, Longitudinal Studies, Male, Middle Aged, Prevalence, Prospective Studies, Risk Factors, Stroke therapy, Treatment Outcome, Foramen Ovale, Patent complications, Heart Septal Defects, Ventricular complications, Ischemic Attack, Transient complications, Stroke complications, Thrombophilia diagnosis, Thrombophilia epidemiology, Thrombophilia etiology
- Abstract
Introduction: Data are limited on the optimal management of cryptogenic TIA/stroke patients with a patent foramen ovale (PFO)±inter-atrial septal aneurysm (IASA), especially with an inherited thrombophilia., Methods: Prospectively-collected data on TIA/ischaemic stroke patients with PFO, IASA or both who received 'goal-directed secondary-prevention medical treatment' were analysed. All patients had trans-oesophageal echocardiography, anti-nuclear, anti-cardiolipin, anti-beta 2 glycoprotein I antibodies, rheumatoid factor, lupus anticoagulant, protein C&S, anti-thrombin, factor VIII activity, activated protein C resistance, Factor V Leiden, prothrombin gene and MTHFR-c.677C>T mutation screening. ENA and homocysteine were assessed in the latter study period., Results: Eighty-three patients were recruited. Mean follow-up: 48.1months. Forty-seven patients (56.6%) had an isolated PFO, 32 (38.6%) a PFO and an IASA, and 4 (4.8%) an IASA alone. Eighteen (21.7%) had ≥1 abnormality on thrombophilia screening. The most important abnormalities which lead to treatment changes in 11 patients (13.3%) were primary anti-phospholipid syndrome (N=3; 3.6%), protein S deficiency (N=2; 2.4%) hyper-homocysteinaemia (N=6/72 screened, 8.3%). Four patients (4.8%) opted for PFO closure: two with protein S deficiency, and two with no identified thrombophilia. Seven (8.4%) had recurrent TIA/ischaemic stroke during follow-up (overall annualised incidence: 2.1%), of whom five had a PFO alone and two a PFO and IASA., Discussion: Comprehensive arterial and venous thrombophilia screening is warranted in TIA/ischaemic stroke patients with a PFO±IASA, is conclusively abnormal in over a fifth, and informed important decision-making regarding individualised therapy in 13.3% of patients. The incidence of recurrent vascular events in this population is low on optimal, personalised secondary-prevention treatment, even with an underlying thrombophilia., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2017
- Full Text
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