Comparison of VerifyNow, thromboelastography, and PL-12 in patients with minor ischemic stroke or transient ischemic attack

The value of thromboelastography in evaluating the efficacy of Xueshuantong combined with edaravone in the treatment of acute cerebral infarction

To explore the value of thromboelastography (TEG) in evaluating the efficacy of Xueshuantong combined with edaravone for the treatment of acute cerebral infarction (ACI). We retrospectively analyzed the clinical data of 96 patients with ACI treated with Xueshuantong combined with edaravone and monitored by TEG. The correlation between the results of TEG examination and treatment outcomes in patients after treatment was analyzed. After treatment, 65 of 96 patients showed good efficacy and 31 had poor efficacy. kinetic time (KT), reaction time (RT), and the percentage of clot lysis at 30 minutes after Ma value (LY30) of patients with good therapeutic effects were significantly higher than those with poor therapeutic effects; However, maximum amplitude (MA) and coagulation index (CI) were significantly lower than those with poor efficacy (P < .05). There was a significant positive correlation between KT, RT, and LY30 and the therapeutic effect of ACI, and a significant negative correlation between the therapeutic effects of MA, CI, and ACI (P < .05). Logistic analysis confirmed that KT, RT, and LY30 were protective factors for the therapeutic effect of ACI; MA and CI were risk factors for the therapeutic effect of ACI (P < .05). TEG has a high value in evaluating the efficacy of Xueshuantong combined with edaravone in the treatment of ACI. It can clarify changes in the coagulation function of patients, thereby guiding clinical follow-up treatment.

Rapid and Nondestructive Evaluation of Platelet Function in Whole Blood by Microfluidic Deterministic Cytometry

Platelet size is a determinant of platelet function. Here, a new microfluidic deterministic cytometry packed with S-shaped micropillars (S-MDC) was developed to rapidly and sensitively determine the apparent size (Dapp) of platelets, which was used to evaluate platelet function. The platelet Dapp in the diluted whole blood was rapidly and label-freely measured by S-MDC within 2 min under shear rates (0.4 mm/s) that mimicked physiological conditions. The level of CD62p on platelets scarcely changed before and after platelets went through the whole S-MDC, indicating that the platelet function was nondestructive. Notably, the human platelet Dapp determined before and after thrombin addition by S-MDC was highly coincident with the levels of CD62p on the platelet surface by flow cytometry (r = 0.819), revealing that the human platelet Dapp was available to assess the platelet activation state. In addition, the results of the rat platelet Dapp were consistent with myocardial injury of rats with myocardial ischemia before and after treatment with antiplatelet agents, suggesting that rat platelet Dapp can be used to reflect myocardial injury in vivo outcomes. These findings reveal that S-MDC is a promising technique for screening tests for a bleeding disorder, in addition to monitoring antiplatelet drugs.

High on-treatment platelet reactivity is associated with poor outcomes after ischemic stroke: A meta-analysis

OBJECTIVES

High on-treatment platelet reactivity (HTPR) determined by platelet function assays is present in certain patients with ischemic stroke or transient ischemic attack (TIA). However, it is unclear whether HTPR is associated with poor clinical outcomes. Our study aimed to investigate the relationship of HTPR with recurrent vascular events in ischemic stroke or TIA.

METHODS

Pubmed (MEDLINE), EMBASE, and Cochrane Library were searched for eligible studies from inception to January 1, 2022. Stata 17.0 software was used to calculate the risk ratio (RR). Subgroup and sensitivity analyses were conducted to assess the source of heterogeneity. A random-effects model was used when heterogeneity was present. Primary endpoint of the meta-analysis was the risk ratio of recurrent vascular events in HTPR Patients. While stroke and TIA, all-cause death, early neurological deterioration, early new ischemic lesions, and stroke severity measured by National Institute of Health Stroke Scale (NIHSS) scores at admission were also pooled.

RESULTS

Thirty articles (7995 patients) were eligible including 28 cohort studies and 2 prospective case-control studies. The prevalence of HTPR varied from 5.9% to 60%. HTPR was associated with an increased risk of recurrent vascular events (RR = 2.94, 95% CI 2.04-4.23), stroke recurrence (RR = 2.05; 95% CI 1.43-2.95), and all-cause mortality (RR = 2.43; 95% CI 1.83-3.22). Subgroup analysis showed that HTPR determined by optical aggregometry, Verify-Now system and 11dh TXB2 is related to a higher risk of recurrent vascular events (RR = 3.53, 95% CI 1.51-9.40; RR = 2.16, 95% CI 1.02-4.56; RR = 3.76, 95% CI 1.51-9.40, respectively). Moreover, patients with HTPR had an increased incidence of early neurological deterioration (RR = 2.75; 95% CI 1.76-4.30) and higher NIHSS scores at admission (Mean difference 0.19, 95% CI 0.01-0.36).

CONCLUSIONS

This meta-analysis demonstrates HTPR is associated with higher risk of recurrent vascular events, early neurological deterioration and increased severity in patients with ischemic stroke and TIA. HTPR measured by platelet function assays may guide the use of antiplatelet agents in ischemic stroke and TIA.

Comparison of Different Laboratory Tests to Identify “Aspirin Resistance” and Risk of Vascular Events among Ischaemic Stroke Patients: A Double-Blind Study

“Aspirin resistance” (AR) is associated with increased risk of vascular events. We aimed to compare different platelet function tests used in identifying AR and assess their implications on clinical outcome. We performed platelet aggregation studies on non-cardioembolic ischaemic stroke patients taking aspirin 100 mg/day and 30 non-stroke controls. Data were collected on demographics, vascular risk factors, and concomitant medications. Cut-offs for AR were (1) light transmission aggregometry (LTA) of ≥20% using arachidonic acid (AA), ≥70% using ADP, or ≥60% using collagen; and (2) VerifyNow® assay ≥ 550 ARU. Telephone follow-ups were conducted by study staff blinded to AR status to ascertain the occurrence of vascular outcomes (stroke, myocardial infarction, amputation, death). A total of 113 patients were recruited, mean age 65 ± 8 years, 47% women, 45 ± 15 days from index stroke. 50 (44.3%, 95% CI 34.9–53.9) had AR on at least 1 test. Frequency of AR varied from 0% to 39% depending on method used and first vs. recurrent stroke. There were strong correlations between LTA AA, VerifyNow® and Multiplate® ASPItest (r = 0.7457–0.8893), but fair to poor correlation between LTA collagen and Multiplate® COLtest (r = 0.5887) and between LTA ADP and Multiplate® ADPtest (r = 0.0899). Of 103 patients with a mean follow up of 801 ± 249 days, 10 (9.7%) had vascular outcomes, of which six had AR by LTA-ADP. AR by LTA-ADP is associated with increased risk of vascular outcome (p = 0.034). Identification of AR is not consistent across different platelet function tests. LTA of ≥70% using 10 µM ADP in post-stroke patients taking aspirin is associated with increased risk of vascular outcome.

Viscoelastic Testing and Coagulopathy of Traumatic Brain Injury

A unique coagulopathy often manifests following traumatic brain injury, leading the clinician down a difficult decision path on appropriate prophylaxis and therapy. Conventional coagulation assays—such as prothrombin time, partial thromboplastin time, and international normalized ratio—have historically been utilized to assess hemostasis and guide treatment following traumatic brain injury. However, these plasma-based assays alone often lack the sensitivity to diagnose and adequately treat coagulopathy associated with traumatic brain injury. Here, we review the whole blood coagulation assays termed viscoelastic tests and their use in traumatic brain injury. Modified viscoelastic tests with platelet function assays have helped elucidate the underlying pathophysiology and guide clinical decisions in a goal-directed fashion. Platelet dysfunction appears to underlie most coagulopathies in this patient population, particularly at the adenosine diphosphate and/or arachidonic acid receptors. Future research will focus not only on the utility of viscoelastic tests in diagnosing coagulopathy in traumatic brain injury, but also on better defining the use of these tests as evidence-based and/or precision-based tools to improve patient outcomes.