Prediction of residual ischemic risk in ticagrelor-treated patients with acute coronary syndrome

Platelet-derived circFAM13B associated with anti-platelet responsiveness of ticagrelor in patients with acute coronary syndrome

BACKGROUND

Platelet is enriched with Circular RNAs (circRNAs), with circFAM13B rank among the 10 most abundant circRNAs in platelets. The aim of the present study was to evaluate the predictive value of platelet-derived circFAM13B for the antiplatelet responsiveness and efficacy of ticagrelor in patients with acute coronary syndrome (ACS).

METHODS

Consecutive ACS patients treated with ticagrelor were enrolled, and the antiplatelet responsiveness of 3 days of ticagrelor maintenance treatment was assessed by measuring the adenosine diphosphate (ADP)-induced platelet inhibition rate (ADP%) using thromboelastography. The expression of circFAM13B in the patients' platelets was analyzed by quantitative real-time polymerase chain reaction. The correlation between circFAM13B expression and ticagrelor antiplatelet responsiveness, as well as the independent contribution of circFAM13B to the composite of adverse ischemic events during a follow-up period of at least 12 months was evaluated.

RESULTS

A total of 129 eligible ACS patients treated with ticagrelor were enrolled in the study. A negative correlation was found between the expression of circFAM13B and the ADP% value (r = -0.41, P < 0.001). Patients with ADP% ≥ 76% had a significantly lower level of circFAM13B compared to those with ADP% < 76% (adjusted P = 0.009). Receiver operating characteristic curve analysis demonstrated that combining circFAM13B expression > 1.05 with clinical risk factors could effectively predict the risk of adverse ischemic events (AUC = 0.81, 95% CI: 0.69 to 0.92, P < 0.001). Kaplan-Meier survival analysis showed that patients with circFAM13B > 1.05 had a significantly higher risk of adverse ischemic events compared to those with circFAM13B ≤ 1.05 (P = 0.003). Multivariate logistic hazard analysis identified circFAM13B > 1.05 as an independent risk factor for adverse ischemic events in in ticagrelor-treated ACS patients (adjusted OR: 5.60, 95% CI: 1.69-18.50; P = 0.005).

CONCLUSIONS

Platelet-derived circFAM13B could be utilized for predicting the antiplatelet responsiveness and efficacy of ticagrelor in patients with ACS.

Time to maximum amplitude of thromboelastography can predict mortality in patients with severe COVID-19: a retrospective observational study

Objective

To predict mortality in severe patients with COVID-19 at admission to the intensive care unit (ICU) using thromboelastography (TEG).

Methods

This retrospective, two-center, observational study involved 87 patients with PCR-and chest CT-confirmed severe COVID-19 who were admitted to at Wuhan Huoshenshan Hospital and the 908th Hospital of Chinese PLA Logistic Support Force between February 2020 and February 2023. Clinic demographics, laboratory results, and outcomes were compared between those who survived and those who died during hospitalization.

Results

Thromboelastography showed that of the 87 patients, 14 were in a hypercoagulable state, 25 were in a hypocoagulable state, and 48 were normal, based on the time to maximum amplitude (TMA). Patients who died showed significantly lower α angle, but significantly longer R-time, K-time and TMA than patients who survived. Random forest selection showed that K-time, TMA, prothrombin time (PT), international normalized ratio (INR), D-dimer, C-reactive protein (CRP), aspartate aminotransferase (AST), and total bilirubin (Tbil) were significant predictors. Multivariate logistic regression identified that TMA and CRP were independently associated with mortality. TMA had a greater predictive power than CRP levels based on time-dependent AUCs. Patients with TMA ≥ 26.4 min were at significantly higher risk of mortality (hazard ratio 3.99, 95% Confidence Interval, 1.92-8.27, p < 0.01).

Conclusion

TMA ≥26.4 min at admission to ICU may be an independent predictor of in-hospital mortality for patients with severe COVID-19.

Advances and Perspectives in methods for identifying high platelet reactivity

Antiplatelet therapy is the foundational treatment for the prevention and treatment of coronary and cerebrovascular ischemic events in patients with coronary heart disease, ischemic stroke, and transient ischemic attack (TIA). However, with more and more studies reporting an increased risk of thrombosis in some patients due to poor response to therapeutic agents, the selection of appropriate P2Y12 inhibitors has become a major challenge that needs to be addressed urgently. Currently, commonly used oral P2Y12 inhibitors include clopidogrel, ticagrelor, and prasugrel. Assessing patients' risk factors before the development of treatment regimens by effectively predicting the risk of high platelet reactivity with specific P2Y12 inhibitors in advance to avert the occurrence of major adverse cardiovascular and cerebrovascular events (MACCE) is the key point to the problem. Up to now, methods available for predicting platelet reactivity include genetic testing, platelet function testing, and risk scores. This review provides a summarization of the existent available identification methods and analyzes the advantages and drawbacks of different methods in specific clinical settings, intending to guide the rational clinical application of P2Y12 receptor inhibitors.

Modified Thromboelastography for Peri-interventional Assessment of Platelet Function in Cardiology Patients: A Narrative Review

Viscoelastic testing (VET), such as thromboelastography, can measure whole blood coagulation dynamics in real time and is used across a range of clinical settings, including cardiac surgery, liver transplant, and trauma. The use of modified thromboelastography with platelet function assessment (TEG(R) PlateletMapping(R) Assay) can provide an analysis of platelet contribution to hemostasis, including the contribution of the P2Y12 receptor and thromboxane pathway to platelet function. The TEG PlateletMapping Assay has shown high correlation with the current gold standard test of platelet function, light transmission aggregometry, to measure arachidonic acid and adenosine diphosphate agonist-induced platelet activation. Studies have also shown comparable results with other whole blood platelet function tests. In this review, we explore the clinical applications of modified thromboelastography with platelet function assessment. This includes guiding dual antiplatelet therapy in relation to cardiac procedures, such as percutaneous coronary interventions, transcatheter aortic valve replacement, and left atrial appendage closure. We also explore the developing use of thromboelastography in the emergency care setting of coronavirus disease 2019, which is commonly associated with a hypercoagulable and hypofibrinolytic state. Despite a general lack of high-quality, grade 1 evidence regarding the use of modified thromboelastography with platelet function assessment in these disease areas, the ability of the TEG PlateletMapping Assay to measure global hemostasis and platelet reactivity rapidly and to view and evaluate results at the point of care makes it a promising area for further study for managing patient treatment and optimizing hemostatic therapy.