Displaying publications 1 - 20 of 31 in total

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  1. Blair GW, Appleton JP, Flaherty K, Doubal F, Sprigg N, Dooley R, et al.
    EClinicalMedicine, 2019 04 24;11:34-43.
    PMID: 31317131 DOI: 10.1016/j.eclinm.2019.04.001
    Background: Lacunar stroke, a frequent clinical manifestation of small vessel disease (SVD), differs pathologically from other ischaemic stroke subtypes and has no specific long-term secondary prevention. Licenced drugs, isosorbide mononitrate (ISMN) and cilostazol, have relevant actions to prevent SVD progression.

    Methods: We recruited independent patients with clinically confirmed lacunar ischaemic stroke without cognitive impairment to a prospective randomised clinical trial, LACunar Intervention-1 (LACI-1). We randomised patients using a central web-based system, 1:1:1:1 with minimisation, to masked ISMN 25 mg bd, cilostazol 100 mg bd, both ISMN and cilostazol started immediately, or both with start delayed. We escalated doses to target over two weeks, sustained for eight weeks. Primary outcome was the proportion achieving target dose. Secondary outcomes included symptoms, safety (haemorrhage, recurrent vascular events), cognition, haematology, vascular function, and neuroimaging. LACI-1 was powered (80%, alpha 0.05) to detect 35% (90% versus 55%) difference between the proportion reaching target dose on one versus both drugs at 55 patients. Registration ISRCTN12580546.

    Findings: LACI-1 enrolled 57 participants between March 2016 and August 2017: 18 (32%) females, mean age 66 (SD 11, range 40-85) years, onset-randomisation 203 (range 6-920) days. Most achieved full (64%) or over half (87%) dose, with no difference between cilostazol vs ISMN, single vs dual drugs. Headache and palpitations increased initially then declined similarly with dual versus single drugs. There was no between-group difference in BP, pulse-wave velocity, haemoglobin or platelet function, but pulse rate was higher (mean difference, MD, 6.4, 95%CI 1.2-11.7, p = 0.02), platelet count higher (MD 35.7, 95%CI 2.8, 68.7, p = 0.03) and white matter hyperintensities reduced more (Chi-square p = 0.007) with cilostazol versus no cilostazol.

    Interpretation: Cilostazol and ISMN are well tolerated when the dose is escalated, without safety concerns, in patients with lacunar stroke. Larger trials with longer term follow-up are justified.

    Funding: Alzheimer's Society (AS-PG-14-033).

  2. Blair GW, Appleton JP, Law ZK, Doubal F, Flaherty K, Dooley R, et al.
    Int J Stroke, 2018 07;13(5):530-538.
    PMID: 28906205 DOI: 10.1177/1747493017731947
    Rationale The pathophysiology of most lacunar stroke, a form of small vessel disease, is thought to differ from large artery atherothrombo- or cardio-embolic stroke. Licensed drugs, isosorbide mononitrate and cilostazol, have promising mechanisms of action to support their testing to prevent stroke recurrence, cognitive impairment, or radiological progression after lacunar stroke. Aim LACI-1 will assess the tolerability, safety, and efficacy, by dose, of isosorbide mononitrate and cilostazol, alone and in combination, in patients with ischemic lacunar stroke. Sample size A sample of 60 provides 80+% power (significance 0.05) to detect a difference of 35% (90% versus 55%) between those reaching target dose on one versus both drugs. Methods and design LACI-1 is a phase IIa partial factorial, dose-escalation, prospective, randomized, open label, blinded endpoint trial. Participants are randomized to isosorbide mononitrate and/or cilostazol for 11 weeks with dose escalation to target as tolerated in two centers (Edinburgh, Nottingham). At three visits, tolerability, safety, blood pressure, pulse wave velocity, and platelet function are assessed, plus magnetic resonance imaging to assess cerebrovascular reactivity in a subgroup. Study outcomes Primary: proportion of patients completing study achieving target maximum dose. Secondary symptoms whilst taking medications; safety (hemorrhage, recurrent vascular events, falls); blood pressure, platelet function, arterial stiffness, and cerebrovascular reactivity. Discussion This study will inform the design of a larger phase III trial of isosorbide mononitrate and cilostazol in lacunar stroke, whilst providing data on the drugs' effects on vascular and platelet function. Trial registration ISRCTN (ISRCTN12580546) and EudraCT (2015-001953-33).
  3. Appleton JP, Blair GW, Flaherty K, Law ZK, May J, Woodhouse LJ, et al.
    Front Neurol, 2019;10:723.
    PMID: 31333572 DOI: 10.3389/fneur.2019.00723
    Background: Cilostazol and isosorbide mononitrate (ISMN) are candidate treatments for cerebral small vessel disease and lacunar ischaemic stroke. As both drugs may influence hemoglobin and platelet count, and hemodynamics, we sought to assess their effects in the lacunar intervention-1 (LACI-1) trial. Methods: Fifty-seven lacunar ischaemic stroke patients were randomized to immediate ISMN, cilostazol, or their combination for 9 weeks in addition to guideline stroke prevention. A fourth group received both drugs with a delayed start. Full blood count, platelet function, peripheral blood pressure (BP), heart rate and central hemodynamics (Augmentation index, Buckberg index) were measured at baseline, and weeks 3 and 8. Differences were assessed by multiple linear regression adjusted for baseline and key prognostic variables. Registration ISRCTN 12580546. Results: At week 8, platelet count was higher with cilostazol vs. no cilostazol (mean difference, MD 35.73, 95% confidence intervals, 95% CI 2.81-68.66, p = 0.033), but no significant differences were noted for hemoglobin levels or platelet function. At week 8, BP did not differ between the treatment groups, whilst heart rate was higher in those taking cilostazol vs. no cilostazol (MD 6.42, 95% CI 1.17-11.68, p = 0.017). Buckberg index (subendocardial perfusion) was lower in those randomized to cilostazol vs. no cilostazol and in those randomized to both drugs vs. either drug. Whilst ISMN significantly increased unadjusted augmentation index (arterial stiffness, MD 21.19, 95% CI 9.08-33.31, p = 0.001), in isolation both drugs non-significantly reduced augmentation index adjusted for heart rate. Conclusions: Cilostazol increased heart rate and platelet count, and reduced Buckberg index, whilst both drugs may individually reduce arterial stiffness adjusted for heart rate. Neither drug had clinically significant effects on hemoglobin or platelet function over 8 weeks. Further assessment of the safety and efficacy of these medications following lacunar ischaemic stroke is warranted.
  4. Flaherty K, Bath PM, Dineen R, Law Z, Scutt P, Pocock S, et al.
    Trials, 2017 Dec 20;18(1):607.
    PMID: 29262841 DOI: 10.1186/s13063-017-2341-5
    RATIONALE: Aside from blood pressure lowering, treatment options for intracerebral haemorrhage remain limited and a proportion of patients will undergo early haematoma expansion with resultant significant morbidity and mortality. Tranexamic acid (TXA), an anti-fibrinolytic drug, has been shown to significantly reduce mortality in patients, who are bleeding following trauma, when given rapidly. TICH-2 is testing whether TXA is effective at improving outcome in spontaneous intracerebral haemorrhage (SICH).

    METHODS AND DESIGN: TICH-2 is a pragmatic, phase III, prospective, double-blind, randomised placebo-controlled trial. Two thousand adult (aged ≥ 18 years) patients with an acute SICH, within 8 h of stroke onset, will be randomised to receive TXA or the placebo control. The primary outcome is ordinal shift of modified Rankin Scale score at day 90. Analyses will be performed using intention-to-treat.

    RESULTS: This paper and its attached appendices describe the statistical analysis plan (SAP) for the trial and were developed and published prior to database lock and unblinding to treatment allocation. The SAP includes details of analyses to be undertaken and unpopulated tables which will be reported in the primary and key secondary publications. The database will be locked in early 2018, ready for publication of the results later in the same year.

    DISCUSSION: The SAP details the analyses that will be done to avoid bias arising from prior knowledge of the study findings. The trial will determine whether TXA can improve outcome after SICH, which currently has no definitive therapy.

    TRIAL REGISTRATION: ISRCTN registry, ID: ISRCTN93732214 . Registered on 17 January 2013.

  5. Law ZK, Dineen R, England TJ, Cala L, Mistri AK, Appleton JP, et al.
    Transl Stroke Res, 2021 Apr;12(2):275-283.
    PMID: 32902808 DOI: 10.1007/s12975-020-00845-6
    Neurological deterioration is common after intracerebral hemorrhage (ICH). We aimed to identify the predictors and effects of neurological deterioration and whether tranexamic acid reduced the risk of neurological deterioration. Data from the Tranexamic acid in IntraCerebral Hemorrhage-2 (TICH-2) randomized controlled trial were analyzed. Neurological deterioration was defined as an increase in National Institutes of Health Stroke Scale (NIHSS) of ≥ 4 or a decline in Glasgow Coma Scale of ≥ 2. Neurological deterioration was considered to be early if it started ≤ 48 h and late if commenced between 48 h and 7 days after onset. Logistic regression was used to identify predictors and effects of neurological deterioration and the effect of tranexamic acid on neurological deterioration. Of 2325 patients, 735 (31.7%) had neurological deterioration: 590 (80.3%) occurred early and 145 (19.7%) late. Predictors of early neurological deterioration included recruitment from the UK, previous ICH, higher admission systolic blood pressure, higher NIHSS, shorter onset-to-CT time, larger baseline hematoma, intraventricular hemorrhage, subarachnoid extension and antiplatelet therapy. Older age, male sex, higher NIHSS, previous ICH and larger baseline hematoma predicted late neurological deterioration. Neurological deterioration was independently associated with a modified Rankin Scale of > 3 (aOR 4.98, 3.70-6.70; p 
  6. Law ZK, Ali A, Krishnan K, Bischoff A, Appleton JP, Scutt P, et al.
    Stroke, 2020 01;51(1):121-128.
    PMID: 31735141 DOI: 10.1161/STROKEAHA.119.026128
    Background and Purpose- Blend, black hole, island signs, and hypodensities are reported to predict hematoma expansion in acute intracerebral hemorrhage. We explored the value of these noncontrast computed tomography signs in predicting hematoma expansion and functional outcome in our cohort of intracerebral hemorrhage. Methods- The TICH-2 (Tranexamic acid for IntraCerebral Hemorrhage-2) was a prospective randomized controlled trial exploring the efficacy and safety of tranexamic acid in acute intracerebral hemorrhage. Baseline and 24-hour computed tomography scans of trial participants were analyzed. Hematoma expansion was defined as an increase in hematoma volume of >33% or >6 mL on 24-hour computed tomography. Poor functional outcome was defined as modified Rankin Scale of 4 to 6 at day 90. Multivariable logistic regression was performed to identify predictors of hematoma expansion and poor functional outcome. Results- Of 2325 patients recruited, 2077 (89.3%) had valid baseline and 24-hour scans. Five hundred seventy patients (27.4%) had hematoma expansion while 1259 patients (54.6%) had poor functional outcome. The prevalence of noncontrast computed tomography signs was blend sign, 366 (16.1%); black hole sign, 414 (18.2%); island sign, 200 (8.8%); and hypodensities, 701 (30.2%). Blend sign (adjusted odds ratio [aOR] 1.53 [95% CI, 1.16-2.03]; P=0.003), black hole (aOR, 2.03 [1.34-3.08]; P=0.001), and hypodensities (aOR, 2.06 [1.48-2.89]; P<0.001) were independent predictors of hematoma expansion on multivariable analysis with adjustment for covariates. Black hole sign (aOR, 1.52 [1.10-2.11]; P=0.012), hypodensities (aOR, 1.37 [1.05-1.78]; P=0.019), and island sign (aOR, 2.59 [1.21-5.55]; P=0.014) were significant predictors of poor functional outcome. Tranexamic acid reduced the risk of hematoma expansion (aOR, 0.77 [0.63-0.94]; P=0.010), but there was no significant interaction between the presence of noncontrast computed tomography signs and benefit of tranexamic acid on hematoma expansion and functional outcome (P interaction all >0.05). Conclusions- Blend sign, black hole sign, and hypodensities predict hematoma expansion while black hole sign, hypodensities, and island signs predict poor functional outcome. Noncontrast computed tomography signs did not predict a better response to tranexamic acid. Clinical Trial Registration- URL: https://www.isrctn.com. Unique identifier: ISRCTN93732214.
  7. Seiffge DJ, Polymeris AA, Law ZK, Krishnan K, Zietz A, Thilemann S, et al.
    Ann Neurol, 2022 Dec;92(6):921-930.
    PMID: 36054211 DOI: 10.1002/ana.26481
    OBJECTIVE: We assessed whether hematoma expansion (HE) and favorable outcome differ according to type of intracerebral hemorrhage (ICH).

    METHODS: Among participants with ICH enrolled in the TICH-2 (Tranexamic Acid for Hyperacute Primary Intracerebral Haemorrhage) trial, we assessed baseline scans for hematoma location and presence of cerebral amyloid angiopathy (CAA) using computed tomography (CT, simplified Edinburgh criteria) and magnetic resonance imaging (MRI; Boston criteria) and categorized ICH as lobar CAA, lobar non-CAA, and nonlobar. The main outcomes were HE and favorable functional outcome. We constructed multivariate regression models and assessed treatment effects using interaction terms.

    RESULTS: A total of 2,298 out of 2,325 participants were included with available CT (98.8%; median age = 71 years, interquartile range = 60-80 years; 1,014 female). Additional MRI was available in 219 patients (9.5%). Overall, 1,637 participants (71.2%) had nonlobar ICH; the remaining 661 participants (28.8%) had lobar ICH, of whom 202 patients had lobar CAA-ICH (8.8%, 173 participants according to Edinburgh and 29 participants according to Boston criteria) and 459 did not (lobar non-CAA, 20.0%). For HE, we found a significant interaction of lobar CAA ICH with time from onset to randomization (increasing risk with time, pinteraction  

  8. Law ZK, Appleton JP, Scutt P, Roberts I, Al-Shahi Salman R, England TJ, et al.
    Stroke, 2022 Apr;53(4):1141-1148.
    PMID: 34847710 DOI: 10.1161/STROKEAHA.121.035191
    BACKGROUND: Seeking consent rapidly in acute stroke trials is crucial as interventions are time sensitive. We explored the association between consent pathways and time to enrollment in the TICH-2 (Tranexamic Acid in Intracerebral Haemorrhage-2) randomized controlled trial.

    METHODS: Consent was provided by patients or by a relative or an independent doctor in incapacitated patients, using a 1-stage (full written consent) or 2-stage (initial brief consent followed by full written consent post-randomization) approach. The computed tomography-to-randomization time according to consent pathways was compared using the Kruskal-Wallis test. Multivariable logistic regression was performed to identify variables associated with onset-to-randomization time of ≤3 hours.

    RESULTS: Of 2325 patients, 817 (35%) gave self-consent using 1-stage (557; 68%) or 2-stage consent (260; 32%). For 1507 (65%), consent was provided by a relative (1 stage, 996 [66%]; 2 stage, 323 [21%]) or a doctor (all 2-stage, 188 [12%]). One patient did not record prerandomization consent, with written consent obtained subsequently. The median (interquartile range) computed tomography-to-randomization time was 55 (38-93) minutes for doctor consent, 55 (37-95) minutes for 2-stage patient, 69 (43-110) minutes for 2-stage relative, 75 (48-124) minutes for 1-stage patient, and 90 (56-155) minutes for 1-stage relative consents (P<0.001). Two-stage consent was associated with onset-to-randomization time of ≤3 hours compared with 1-stage consent (adjusted odds ratio, 1.9 [95% CI, 1.5-2.4]). Doctor consent increased the odds (adjusted odds ratio, 2.3 [1.5-3.5]) while relative consent reduced the odds of randomization ≤3 hours (adjusted odds ratio, 0.10 [0.03-0.34]) compared with patient consent. Only 2 of 771 patients (0.3%) in the 2-stage pathways withdrew consent when full consent was sought later. Two-stage consent process did not result in higher withdrawal rates or loss to follow-up.

    CONCLUSIONS: The use of initial brief consent was associated with shorter times to enrollment, while maintaining good participant retention. Seeking written consent from relatives was associated with significant delays.

    REGISTRATION: URL: https://www.isrctn.com; Unique identifier: ISRCTN93732214.

  9. Sprigg N, Flaherty K, Appleton JP, Al-Shahi Salman R, Bereczki D, Beridze M, et al.
    Lancet, 2018 May 26;391(10135):2107-2115.
    PMID: 29778325 DOI: 10.1016/S0140-6736(18)31033-X
    BACKGROUND: Tranexamic acid can prevent death due to bleeding after trauma and post-partum haemorrhage. We aimed to assess whether tranexamic acid reduces haematoma expansion and improves outcome in adults with stroke due to intracerebral haemorrhage.

    METHODS: We did an international, randomised placebo-controlled trial in adults with intracerebral haemorrhage from acute stroke units at 124 hospital sites in 12 countries. Participants were randomly assigned (1:1) to receive 1 g intravenous tranexamic acid bolus followed by an 8 h infusion of 1 g tranexamic acid or a matching placebo, within 8 h of symptom onset. Randomisation was done centrally in real time via a secure website, with stratification by country and minimisation on key prognostic factors. Treatment allocation was concealed from patients, outcome assessors, and all other health-care workers involved in the trial. The primary outcome was functional status at day 90, measured by shift in the modified Rankin Scale, using ordinal logistic regression with adjustment for stratification and minimisation criteria. All analyses were done on an intention-to-treat basis. This trial is registered with the ISRCTN registry, number ISRCTN93732214.

    FINDINGS: We recruited 2325 participants between March 1, 2013, and Sept 30, 2017. 1161 patients received tranexamic acid and 1164 received placebo; the treatment groups were well balanced at baseline. The primary outcome was assessed for 2307 (99%) participants. The primary outcome, functional status at day 90, did not differ significantly between the groups (adjusted odds ratio [aOR] 0·88, 95% CI 0·76-1·03, p=0·11). Although there were fewer deaths by day 7 in the tranexamic acid group (101 [9%] deaths in the tranexamic acid group vs 123 [11%] deaths in the placebo group; aOR 0·73, 0·53-0·99, p=0·0406), there was no difference in case fatality at 90 days (250 [22%] vs 249 [21%]; adjusted hazard ratio 0·92, 95% CI 0·77-1·10, p=0·37). Fewer patients had serious adverse events after tranexamic acid than after placebo by days 2 (379 [33%] patients vs 417 [36%] patients), 7 (456 [39%] vs 497 [43%]), and 90 (521 [45%] vs 556 [48%]).

    INTERPRETATION: Functional status 90 days after intracerebral haemorrhage did not differ significantly between patients who received tranexamic acid and those who received placebo, despite a reduction in early deaths and serious adverse events. Larger randomised trials are needed to confirm or refute a clinically significant treatment effect.

    FUNDING: National Institute of Health Research Health Technology Assessment Programme and Swiss Heart Foundation.

  10. Law ZK, Appleton JP, Bath PM, Sprigg N
    Clin Med (Lond), 2017 Apr;17(2):166-172.
    PMID: 28365631 DOI: 10.7861/clinmedicine.17-2-166
    Managing acute intracerebral haemorrhage is a challenging task for physicians. Evidence shows that outcome can be improved with admission to an acute stroke unit and active care, including urgent reversal of anticoagulant effects and, potentially, intensive blood pressure reduction. Nevertheless, many management issues remain controversial, including the use of haemostatic therapy, selection of patients for neurosurgery and neurocritical care, the extent of investigations for underlying causes and the benefit versus risk of restarting antithrombotic therapy after an episode of intracerebral haemorrhage.
  11. Law ZK, Meretoja A, Engelter ST, Christensen H, Muresan EM, Glad SB, et al.
    Eur Stroke J, 2017 Mar;2(1):13-22.
    PMID: 31008298 DOI: 10.1177/2396987316676610
    Purpose: Haematoma expansion is a devastating complication of intracerebral haemorrhage (ICH) with no established treatment. Tranexamic acid had been an effective haemostatic agent in reducing post-operative and traumatic bleeding. We review current evidence examining the efficacy of tranexamic acid in improving clinical outcome after ICH.

    Method: We searched MEDLINE, EMBASE, CENTRAL and clinical trial registers for studies using search strategies incorporating the terms 'intracerebral haemorrhage', 'tranexamic acid' and 'antifibrinolytic'. Authors of ongoing clinical trials were contacted for further details.

    Findings: We screened 268 publications and retrieved 17 articles after screening. Unpublished information from three ongoing clinical trials was obtained. We found five completed studies. Of these, two randomised controlled trials (RCTs) comparing intravenous tranexamic acid to placebo (n = 54) reported no significant difference in death or dependency. Three observational studies (n = 281) suggested less haematoma growth with rapid tranexamic acid infusion. There are six ongoing RCTs (n = 3089) with different clinical exclusions, imaging selection criteria (spot sign and haematoma volume), time window for recruitment and dosing of tranexamic acid.

    Discussion: Despite their heterogeneity, the ongoing trials will provide key evidence on the effects of tranexamic acid on ICH. There are uncertainties of whether patients with negative spot sign, large haematoma, intraventricular haemorrhage, or poor Glasgow Coma Scale should be recruited. The time window for optimal effect of haemostatic therapy in ICH is yet to be established.

    Conclusion: Tranexamic acid is a promising haemostatic agent for ICH. We await the results of the trials before definite conclusions can be drawn.

  12. Law ZK, England TJ, Mistri AK, Woodhouse LJ, Cala L, Dineen R, et al.
    Eur Stroke J, 2020 Jun;5(2):123-129.
    PMID: 32637645 DOI: 10.1177/2396987320901391
    Introduction: Seizures are common after intracerebral haemorrhage. Tranexamic acid increases the risk of seizures in non-intracerebral haemorrhage population but its effect on post-intracerebral haemorrhage seizures is unknown. We explored the risk factors and outcomes of seizures after intracerebral haemorrhage and if tranexamic acid increased the risk of seizures in the Tranexamic acid for IntraCerebral Haemorrhage-2 trial.

    Patients and methods: Seizures were reported prospectively up to day 90. Cox regression analyses were used to determine the predictors of seizures within 90 days and early seizures (≤7 days). We explored the effect of early seizures on day 90 outcomes.

    Results: Of 2325 patients recruited, 193 (8.3%) had seizures including 163 (84.5%) early seizures and 30 (15.5%) late seizures (>7 days). Younger age (adjusted hazard ratio (aHR) 0.98 per year increase, 95% confidence interval (CI) 0.97-0.99; p = 0.008), lobar haematoma (aHR 5.84, 95%CI 3.58-9.52; p 

  13. Dineen RA, Pszczolkowski S, Flaherty K, Law ZK, Morgan PS, Roberts I, et al.
    BMJ Open, 2018 02 03;8(2):e019930.
    PMID: 29431141 DOI: 10.1136/bmjopen-2017-019930
    OBJECTIVES: To test whether administration of the antifibrinolytic drug tranexamic acid (TXA) in patients with spontaneous intracerebral haemorrhage (SICH) leads to increased prevalence of diffusion-weighted MRI-defined hyperintense ischaemic lesions (primary hypothesis) or reduced perihaematomal oedema volume, perihaematomal diffusion restriction and residual MRI-defined SICH-related tissue damage (secondary hypotheses).

    DESIGN: MRI substudy nested within the double-blind randomised controlled Tranexamic Acid for Hyperacute Primary Intracerebral Haemorrhage (TICH)-2 trial (ISRCTN93732214).

    SETTING: International multicentre hospital-based study.

    PARTICIPANTS: Eligible adults consented and randomised in the TICH-2 trial who were also able to undergo MRI scanning. To address the primary hypothesis, a sample size of n=280 will allow detection of a 10% relative increase in prevalence of diffusion-weighted imaging (DWI) hyperintense lesions in the TXA group with 5% significance, 80% power and 5% imaging data rejection.

    INTERVENTIONS: TICH-2 MRI substudy participants will undergo MRI scanning using a standardised protocol at day ~5 and day ~90 after randomisation. Clinical assessments, randomisation to TXA or placebo and participant follow-up will be performed as per the TICH-2 trial protocol.

    CONCLUSION: The TICH-2 MRI substudy will test whether TXA increases the incidence of new DWI-defined ischaemic lesions or reduces perihaematomal oedema or final ICH lesion volume in the context of SICH.

    ETHICS AND DISSEMINATION: The TICH-2 trial obtained ethical approval from East Midlands - Nottingham 2 Research Ethics Committee (12/EM/0369) and an amendment to allow the TICH-2 MRI sub study was approved in April 2015 (amendment number SA02/15). All findings will be published in peer-reviewed journals. The primary outcome results will also be presented at a relevant scientific meeting.

    TRIAL REGISTRATION NUMBER: ISRCTN93732214; Pre-results.

  14. Salma RA, Law ZK, Bath PM, Steiner T, Sprigg N
    Emergencias, 2020 06;32(3):201-202.
    PMID: 32395931
  15. Law ZK, Al-Shahi Salman R, Bath PM, Steiner T, Sprigg N
    Stroke, 2018 08;49(8):e271-e272.
    PMID: 30355046 DOI: 10.1161/STROKEAHA.118.022071
  16. Law ZK, Desborough M, Roberts I, Al-Shahi Salman R, England TJ, Werring DJ, et al.
    J Am Heart Assoc, 2021 02;10(5):e019130.
    PMID: 33586453 DOI: 10.1161/JAHA.120.019130
    Background Antiplatelet therapy increases the risk of hematoma expansion in intracerebral hemorrhage (ICH) while the effect on functional outcome is uncertain. Methods and Results This is an exploratory analysis of the TICH-2 (Tranexamic Acid in Intracerebral Hemorrhage-2) double-blind, randomized, placebo-controlled trial, which studied the efficacy of tranexamic acid in patients with spontaneous ICH within 8 hours of onset. Multivariable logistic regression and ordinal regression were performed to explore the relationship between pre-ICH antiplatelet therapy, and 24-hour hematoma expansion and day 90 modified Rankin Scale score, as well as the effect of tranexamic acid. Of 2325 patients, 611 (26.3%) had pre-ICH antiplatelet therapy. They were older (mean age, 75.7 versus 66.5 years), more likely to have ischemic heart disease (25.4% versus 2.7%), ischemic stroke (36.2% versus 6.3%), intraventricular hemorrhage (40.2% versus 27.5%), and larger baseline hematoma volume (mean, 28.1 versus 22.6 mL) than the no-antiplatelet group. Pre-ICH antiplatelet therapy was associated with a significantly increased risk of hematoma expansion (adjusted odds ratio [OR], 1.28; 95% CI, 1.01-1.63), a shift toward unfavorable outcome in modified Rankin Scale (adjusted common OR, 1.58; 95% CI, 1.32-1.91) and a higher risk of death at day 90 (adjusted OR, 1.63; 95% CI, 1.25-2.11). Tranexamic acid reduced the risk of hematoma expansion in the overall patients with ICH (adjusted OR, 0.76; 95% CI, 0.62-0.93) and antiplatelet subgroup (adjusted OR, 0.61; 95% CI, 0.41-0.91) with no significant interaction between pre-ICH antiplatelet therapy and tranexamic acid (P interaction=0.248). Conclusions Antiplatelet therapy is independently associated with hematoma expansion and unfavorable functional outcome. Tranexamic acid reduced hematoma expansion regardless of prior antiplatelet therapy use. Registration URL: https://www.isrctn.com; Unique identifier: ISRCTN93732214.
  17. Appleton JP, Law ZK, Woodhouse LJ, Al-Shahi Salman R, Beridze M, Christensen H, et al.
    BMJ Neurol Open, 2023;5(1):e000423.
    PMID: 37337529 DOI: 10.1136/bmjno-2023-000423
    BACKGROUND: Tranexamic acid reduced haematoma expansion and early death, but did not improve functional outcome in the tranexamic acid for hyperacute spontaneous intracerebral haemorrhage-2 (TICH-2) trial. In a predefined subgroup, there was a statistically significant interaction between prerandomisation baseline systolic blood pressure (SBP) and the effect of tranexamic acid on functional outcome (p=0.019).

    METHODS: TICH-2 was an international prospective double-blind placebo-controlled randomised trial evaluating intravenous tranexamic acid in patients with acute spontaneous intracerebral haemorrhage (ICH). Prerandomisation baseline SBP was split into predefined ≤170 and >170 mm Hg groups. The primary outcome at day 90 was the modified Rankin Scale (mRS), a measure of dependency, analysed using ordinal logistic regression. Haematoma expansion was defined as an increase in haematoma volume of >33% or >6 mL from baseline to 24 hours. Data are OR or common OR (cOR) with 95% CIs, with significance at p<0.05.

    RESULTS: Of 2325 participants in TICH-2, 1152 had baseline SBP≤170 mm Hg and were older, had larger lobar haematomas and were randomised later than 1173 with baseline SBP>170 mm Hg. Tranexamic acid was associated with a favourable shift in mRS at day 90 in those with baseline SBP≤170 mm Hg (cOR 0.73, 95% CI 0.59 to 0.91, p=0.005), but not in those with baseline SBP>170 mm Hg (cOR 1.05, 95% CI 0.85 to 1.30, p=0.63). In those with baseline SBP≤170 mm Hg, tranexamic acid reduced haematoma expansion (OR 0.62, 95% CI 0.47 to 0.82, p=0.001), but not in those with baseline SBP>170 mm Hg (OR 1.02, 95% CI 0.77 to 1.35, p=0.90).

    CONCLUSIONS: Tranexamic acid was associated with improved clinical and radiological outcomes in ICH patients with baseline SBP≤170 mm Hg. Further research is needed to establish whether certain subgroups may benefit from tranexamic acid in acute ICH.

    TRIAL REGISTRATION NUMBER: ISRCTN93732214.

  18. Lim ST, Thijs V, Murphy SJX, Fernandez-Cadenas I, Montaner J, Offiah C, et al.
    J Neurol, 2020 Oct;267(10):3021-3037.
    PMID: 32518978 DOI: 10.1007/s00415-020-09932-y
    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.

  19. Kok YE, Pszczolkowski S, Law ZK, Ali A, Krishnan K, Bath PM, et al.
    Radiol Artif Intell, 2022 Nov;4(6):e220096.
    PMID: 36523645 DOI: 10.1148/ryai.220096
    This study evaluated deep learning algorithms for semantic segmentation and quantification of intracerebral hemorrhage (ICH), perihematomal edema (PHE), and intraventricular hemorrhage (IVH) on noncontrast CT scans of patients with spontaneous ICH. Models were assessed on 1732 annotated baseline noncontrast CT scans obtained from the Tranexamic Acid for Hyperacute Primary Intracerebral Haemorrhage (ie, TICH-2) international multicenter trial (ISRCTN93732214), and different loss functions using a three-dimensional no-new-U-Net (nnU-Net) were examined to address class imbalance (30% of participants with IVH in dataset). On the test cohort (n = 174, 10% of dataset), the top-performing models achieved median Dice similarity coefficients of 0.92 (IQR, 0.89-0.94), 0.66 (0.58-0.71), and 1.00 (0.87-1.00), respectively, for ICH, PHE, and IVH segmentation. U-Net-based networks showed comparable, satisfactory performances on ICH and PHE segmentations (P > .05), but all nnU-Net variants achieved higher accuracy than the Brain Lesion Analysis and Segmentation Tool for CT (BLAST-CT) and DeepLabv3+ for all labels (P < .05). The Focal model showed improved performance in IVH segmentation compared with the Tversky, two-dimensional nnU-Net, U-Net, BLAST-CT, and DeepLabv3+ models (P < .05). Focal achieved concordance values of 0.98, 0.88, and 0.99 for ICH, PHE, and ICH volumes, respectively. The mean volumetric differences between the ground truth and prediction were 0.32 mL (95% CI: -8.35, 9.00), 1.14 mL (-9.53, 11.8), and 0.06 mL (-1.71, 1.84), respectively. In conclusion, U-Net-based networks provide accurate segmentation on CT images of spontaneous ICH, and Focal loss can address class imbalance. International Clinical Trials Registry Platform (ICTRP) no. ISRCTN93732214 Supplemental material is available for this article. © RSNA, 2022 Keywords: Head/Neck, Brain/Brain Stem, Hemorrhage, Segmentation, Quantification, Convolutional Neural Network (CNN), Deep Learning Algorithms, Machine Learning Algorithms.
  20. Pszczolkowski S, Law ZK, Gallagher RG, Meng D, Swienton DJ, Morgan PS, et al.
    Comput Biol Med, 2019 03;106:126-139.
    PMID: 30711800 DOI: 10.1016/j.compbiomed.2019.01.022
    BACKGROUND: Spontaneous intracerebral haemorrhage (SICH) is a common condition with high morbidity and mortality. Segmentation of haematoma and perihaematoma oedema on medical images provides quantitative outcome measures for clinical trials and may provide important markers of prognosis in people with SICH.

    METHODS: We take advantage of improved contrast seen on magnetic resonance (MR) images of patients with acute and early subacute SICH and introduce an automated algorithm for haematoma and oedema segmentation from these images. To our knowledge, there is no previously proposed segmentation technique for SICH that utilises MR images directly. The method is based on shape and intensity analysis for haematoma segmentation and voxel-wise dynamic thresholding of hyper-intensities for oedema segmentation.

    RESULTS: Using Dice scores to measure segmentation overlaps between labellings yielded by the proposed algorithm and five different expert raters on 18 patients, we observe that our technique achieves overlap scores that are very similar to those obtained by pairwise expert rater comparison. A further comparison between the proposed method and a state-of-the-art Deep Learning segmentation on a separate set of 32 manually annotated subjects confirms the proposed method can achieve comparable results with very mild computational burden and in a completely training-free and unsupervised way.

    CONCLUSION: Our technique can be a computationally light and effective way to automatically delineate haematoma and oedema extent directly from MR images. Thus, with increasing use of MR images clinically after intracerebral haemorrhage this technique has the potential to inform clinical practice in the future.

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