Hypercoagulability as Measured by Thrombelastography May Be Associated with the Size of Acute Ischemic Infarct-A Pilot Study

Impaired endogenous fibrinolysis status: a potential prognostic predictor in ischemic stroke

Stroke confers a severe global healthcare burden, hence exploring risk factors for stroke occurrence and prognosis is important for stroke prevention and post-stroke management strategies. Endogenous fibrinolysis is a spontaneous physiological protective mechanism that dissolves thrombus to maintain vascular patency. Recently, impaired endogenous fibrinolysis has been considered as a potential novel cardiovascular risk factor, but its link with ischaemic stroke in the past has been underappreciated. In this review, we summarize the latest mechanisms of endogenous fibrinolysis, review the current evidence and data on endogenous fibrinolysis in ischemic stroke. It includes the structure of thrombus in ischemic stroke patients, the effect of fibrin structure on the endogenous fibrinolytic efficiency, and the association between intravenous thrombolytic therapy and endogenous fibrinolysis in ischemic stroke. It also includes the single factors (tissue plasminogen activator, urokinase plasminogen activator, plasminogen activator inhibitor-1, thrombin activatable fibrinolysis inhibitor, complement component 3, complement component 5, alpha-2-antiplasmin, plasmin-alpha-2-antiplasmin complex, and lipoprotein[a]), and the global assessments of endogenous fibrinolysis status (thromboelastography, rotational thromboelastometry, and global thrombosis test), and their potential as predictors to identify occurrence or unfavorable functional outcomes of ischemic stroke. All of these assessments present advantages and limitations, and we suggest that the global thrombosis test may be more appropriate for detecting impaired endogenous fibrinolysis status in ischemic stroke patients.

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.

Alterations of Hemostatic Molecular Markers During Acute Large Vessel Occlusion Stroke

BACKGROUND

This study aimed to investigate regional levels of TAT (thrombin-antithrombin complex), PIC (plasmin-α2 plasmin inhibitor complex), t-PAIC (tissue plasminogen activator-plasminogen activator inhibitor complex), sTM (soluble thrombomodulin), and D-dimer, along with their associations with clinical and procedural characteristics in patients with acute ischemic stroke undergoing endovascular thrombectomy.

METHODS AND RESULTS

We retrospectively analyzed 166 consecutive patients with acute ischemic stroke (62±11.54 years of age, 34.3% women) using prospectively maintained clinical databases and blood samples from local ischemic (proximal to thrombus) and systemic (femoral artery, self-control) arterial compartments. Levels of TAT, PIC, t-PAIC, and D-dimer were significantly elevated, whereas sTM was significantly reduced, in local ischemic regions compared with their systemic levels. Each 1-unit increase in ischemic TAT (adjusted odds ratio [aOR], 1.086 [95% CI, 1.03-1.145]; P=0.002; area under the curve [AUC], 0.833) and PIC (aOR, 1.337 [95% CI, 1.087-1.644]; P=0.006; AUC, 0.771) correlated significantly with higher symptomatic intracranial hemorrhage risk. Additionally, each 1-unit increase in ischemic TAT (aOR, 1.076 [95% CI, 1.016-1.139]; P=0.013; AUC, 0.797), PIC (aOR, 1.554 [95% CI, 1.194-2.022]; P=0.001; AUC, 0.798), and sTM (aOR, 0.769 [95% CI, 0.615-0.961]; P=0.021; AUC, 0.756) was significantly associated with an increased risk of an unfavorable 90-day outcome (modified Rankin scale of 3-6). These hemostatic molecules, individually or combined, significantly improved the predictive power of conventional risk factors, as evidenced by significant increases in net reclassification improvement and integrated discrimination improvement (all P<0.01).

CONCLUSIONS

We observed a hyperactive state of the coagulation-fibrinolysis system within the local ischemic region during hyperacute stroke. Rapid automated measurement of hemostatic molecular markers, particularly TAT, PIC, and sTM, during intra-arterial procedures may provide additional information for stroke risk stratification and therapeutic decision-making, and warrants further investigation.

Thromboelastography as a predictor of functional outcome in acute ischemic stroke patients undergoing endovascular treatment

BACKGROUND

Thromboelastography (TEG) is a useful for predicting hemorrhagic transformation, early neurological deterioration, and functional outcome after stroke. We aimed to investigate whether TEG value could also be useful in predicting functional outcome via various intraprocedural and postprocedural factors in patients with acute large vessel occlusive stroke who underwent intraarterial thrombectomy (IAT).

METHODS

Patients with ischemic stroke who underwent IAT between March 2018 and March 2020 at two tertiary hospitals were included. The association between reaction time (R) and functional outcome was evaluated. The primary outcome was the achievement of functional independence defined as the achievement of a modified Rankin Scale (mRS) score of 0-2 at 3 months after the index stroke.

RESULTS

Among a total of 160 patients (mean age, 70.6 ± 12.3 years; 103 [64.4 %] men), 79 (49.3 %) achieved functional independence at 3 months. R, both as a continuous (odds ratio [OR]: 1.45, 95 % confidence interval [95 % CI]: 1.09-1.92, P = 0.011) and dichotomized parameters (R < 5 min [OR: 0.37, 95 % CI: 0.16-0.82, P = 0.014]), were inversely associated with increased odds of achieving functional independence (mRS score 0-2) after multivariable analysis. The association was still consistent when the outcome was the achievement of disability free (mRS score 0-1) or mRS score analyzed as an ordinal variable.

CONCLUSIONS

Decreased R, especially R < 5 min, was inversely associated with functional outcome pf stroke after EVT.

Clinical Application of Thromboelastography in Acute Ischemic Stroke

Acute ischemic stroke (AIS), characterized by high morbidity and mortality, has imposed a considerable burden on society. Despite rapid development in the treatment of AIS, there is still a high risk of recurrence. Furthermore, there is a time delay in waiting for the results of conventional coagulation tests in candidate patients for intravenous thrombolysis therapy. Heterogeneous responses to antiplatelet, intravascular thrombolysis, and endovascular therapies also worsen the situation. Thromboelastography (TEG), as a global and portable detection method for hemostasis, facilitates clinicians in disease monitoring, treatment evaluation, and prognosis prediction in AIS. In this narrative review, we provided a comprehensive summary of the clinical application of TEG in ischemic stroke and gave insights to further studies.

Clinical and Evolutionary Implications of Dynamic Coagulotoxicity Divergences in Bothrops (Lancehead Pit Viper) Venoms

Despite coagulotoxicity being a primary weapon for prey capture by Bothrops species (lancehead pit vipers) and coagulopathy being a major lethal clinical effect, a genus-wide comparison has not been undertaken. To fill this knowledge gap, we used thromboelastography to compare 37 venoms, from across the full range of geography, taxonomy, and ecology, for their action upon whole plasma and isolated fibrinogen. Potent procoagulant toxicity was shown to be the main venom effect of most of the species tested. However, the most basal species (B. pictus) was strongly anticoagulant; this is consistent with procoagulant toxicity being a novel trait that evolved within Bothrops subsequent to their split from anticoagulant American pit vipers. Intriguingly, two of the arboreal species studied (B. bilineatus and B. taeniatus) lacked procoagulant venom, suggesting differential evolutionary selection pressures. Notably, some terrestrial species have secondarily lost the procoagulant venom trait: the Mogi Mirim, Brazil locality of B. alternatus; San Andres, Mexico locality of B. asper; B. diporus; and the São Roque of B. jararaca. Direct action on fibrinogen was extremely variable; this is consistent with previous hypotheses regarding it being evolutionary decoupled due to procoagulant toxicity being the primary prey-capture weapon. However, human patients live long enough for fibrinogen depletion to be clinically significant. The extreme variability may be reflective of antivenom variability, with these results thereby providing a foundation for such future work of clinical relevance. Similarly, the venom diversification trends relative to ecological niche will also be useful for integration with natural history data, to reconstruct the evolutionary pressures shaping the venoms of these fascinating snakes.