Background:Several platelet function tests are currently used to measure responsiveness to antiplatelet therapy.This study was to compare two tests,light transmittance aggregometry (LTA) and modified thrombelastograph...Background:Several platelet function tests are currently used to measure responsiveness to antiplatelet therapy.This study was to compare two tests,light transmittance aggregometry (LTA) and modified thrombelastography (mTEG),for predicting clinical outcomes in Chinese patients after percutaneous coronary intervention (PCI).Methods:Prospective,observational,single-center study of 789 Chinese patients undergoing PCI was enrolled.This study was investigated the correlations between the two tests and performed receiver operating characteristic curve (ROC) analysis for major adverse cardiovascular events (MACEs) at 1-year follow-up.Results:MACEs occurred in 32 patients (4.1％).Correlations were well between the two tests in the adenosine diphosphate induced platelet reactivity (Spearman r =0.733,P ＜ 0.001).ROC-curve analysis demonstrated that LTA (area under the curve [AUC]:0.677; 95％ confidence interval [CI]:0.643-0.710; P =0.0009),and mTEG (AUC:0.684; 95％ CI:0.650-0.716; P =0.0001) had moderate ability to discriminate between patients with and without MACE.MACE occurred more frequently in patients with high on-treatment platelet reactivity (HPR) when assessed by LTA (7.4％ vs.2.7％; P ＜ 0.001),and by TEG (6.7％ vs.2.6％; P ＜ 0.001).Kaplan-Meier analysis demonstrated that HPR based on the LTA and mTEG was associated with almost 3-fold increased risk of MACE at 1-year follow-up.Conclusions:The correlation between LTA and mTEG is relatively high in Chinese patients.HPR measured by LTA and mTEG were significantly associated with MACE in Chinese patients undergoing PCI.展开更多
BACKGROUND Hemostasis of patients suffering from liver cirrhosis is challenging due to both,pro-and anticoagulatory disorders leading to hemostatic alterations with distinct abnormalities of coagulation.Pathological c...BACKGROUND Hemostasis of patients suffering from liver cirrhosis is challenging due to both,pro-and anticoagulatory disorders leading to hemostatic alterations with distinct abnormalities of coagulation.Pathological changes in conventional coagulation analysis and platelet count are common manifestations of decreased liver synthesis of coagulation factors and reduced platelet count in these patients.However,conventional coagulation analysis and platelet count do not reflect invivo coagulation status or platelet function.The purpose of this present observational study was therefore to assess the haemostatic profile including plasmatic coagulation using thrombelastometry and impedance aggregometry for platelet function in patients suffering from liver cirrhosis.AIM To assess the hemostatic profile of cirrhotic patients according to model for endstage liver disease(MELD)score.METHODS Our study included both in-and outpatients suffering from liver cirrhosis attending the out-and inpatient care of the department of hepatology.Demographic and biochemical data as well as medical history including cause of liver cirrhosis,end stage kidney failure and medication with anticoagulants were recorded.To assess the hemostatic profile,platelet function was analyzed by multiple electrode aggregometry(MEA)using Multiplate^■(ADP-,ASPI-and TRAP-test)and thrombelastometry using ROTEM^■(EXTEM,INTEM,FIBTEM).Data were compared using Mann-Whitney U-or χ^2-test.Spearman correlation was performed to analyze the association between MELD Score and results of thrombelastometry and MEA.RESULTS A total of 68 patients attending the out-and inpatient care suffering from liver cirrhosis were screened.Of these,50 patients were included and assigned to groups according to MELD score 6 to 11(n=25)or≥17(n=25).Baseline patient characteristics revealed significant differences for MELD score(8 vs 22,P<0.0001)and underlying laboratory parameters(international normalized ratio,bilirubine,creatinine)as well as fibrinogen level(275 mg/dL vs 209 mg/dL,展开更多
Background:High on-treatment platelet reactivity (HTPR) has been suggested as a risk factor for patients with ischemic vascular disease.We explored a predictive model of platelet reactivity to clopidogrel and the rela...Background:High on-treatment platelet reactivity (HTPR) has been suggested as a risk factor for patients with ischemic vascular disease.We explored a predictive model of platelet reactivity to clopidogrel and the relationship with clinical outcomes.Methods:A total of 441 patients were included.Platelet reactivity was measured by light transmittance aggregometry after receiving dual antiplatelet therapy.HTPR was defined by the consensus cutoff of maximal platelet aggregation >46% by light transmittance aggregometry.CYP2C19 loss-of-function polymorphisms were identified by DNA microarray analysis.The data were compared by binary logistic regression to find the risk factors.The primary endpoint was major adverse clinical events (MACEs),and patients were followed for a median time of 29 months.Survival curves were constructed with Kaplan-Meier estimates and compared by logrank tests between the patients with HTPR and non-HTPR.Results:The rate of HTPR was 17.2%.Logistic regression identified the following predictors of HTPR:age,therapy regimen,body mass index,diabetes history,CYP2C19^*2,or CYP2C19^*3 variant.The area under the curve of receiver operating characteristic for the HTPR predictive model was 0.793 (95% confidence interval:0.738–0.848).Kaplan-Meier analysis showed that patients with HTPR had a higher incidence of MACE than those with non-HTPR (21.1% vs.9.9%;χ^2 = 7.572,P = 0.010).Conclusions:Our results suggest that advanced age,higher body mass index,treatment with regular dual antiplatelet therapy,diabetes,and CYP2C19^*2 or CYP2C19^*3 carriers are significantly associated with HTPR to clopidogrel.The predictive model of HTPR has useful discrimination and good calibration and may predict long-term MACE.展开更多
Given the broad application of aspirin as antiplatelet drug, availability of standardized methodology to assess potential interaction with any co-medication on platelet aggregation is desired. We characterized the eff...Given the broad application of aspirin as antiplatelet drug, availability of standardized methodology to assess potential interaction with any co-medication on platelet aggregation is desired. We characterized the effect of aspirin (ASA) therapy on collagen-induced platelet aggregation in whole blood to define such methodology. Collagen-induced platelet whole blood aggregation was assessed in 6 healthy male volunteers on 2 occasions (Day 1, Day 7) using the Chronolog aggregometer. From Day 2 up to Day 7, subjects received a daily oral dose of 75 mg ASA. The relationship between collagen dose and platelet aggregation response was assessed. On Day 1, maximal aggregation was observed at 1 μg/mL collagen (15.3 ± 4.6 Ω) and higher. Reproducible results were obtained without any indication of intra-subject fluctuations. ASA treatment decreased maximal aggregation by 80% and 38% at 0.5 and 2.0 μg/mL collagen, respectively. Power calculations were performed based on the observed intra-subject variability and demonstrated minimal sample sizes of 9 - 11 subjects for future cross-over ASA-drug interaction studies exploring effects on platelet aggregation, which demonstrates that the proposed collagen-induced ex vivo whole blood platelet aggregation is a feasible methodology to evaluate ASA-drug interactions in healthy volunteers.展开更多
Various platelet function tests are currently used to identify responsiveness to antiplatelet therapy. 176 ACS patients were enrolled and Linear regression and Kappa consistency analysis showed there was a significant...Various platelet function tests are currently used to identify responsiveness to antiplatelet therapy. 176 ACS patients were enrolled and Linear regression and Kappa consistency analysis showed there was a significant but moderate correlation between platelet inhibition rate and a significant but fair agreement between high clopidogrel on-treatment platelet reactivity tested by light transmission aggregometry and thrombelastography.展开更多
基金This work was supposed by grants from the National Research Key Project of the Twelfth Five-year Plan of Republic of China，National Natural Science Foundation of China，National Special Fund for Healthcare Research in the Public Interests of China
文摘Background:Several platelet function tests are currently used to measure responsiveness to antiplatelet therapy.This study was to compare two tests,light transmittance aggregometry (LTA) and modified thrombelastography (mTEG),for predicting clinical outcomes in Chinese patients after percutaneous coronary intervention (PCI).Methods:Prospective,observational,single-center study of 789 Chinese patients undergoing PCI was enrolled.This study was investigated the correlations between the two tests and performed receiver operating characteristic curve (ROC) analysis for major adverse cardiovascular events (MACEs) at 1-year follow-up.Results:MACEs occurred in 32 patients (4.1％).Correlations were well between the two tests in the adenosine diphosphate induced platelet reactivity (Spearman r =0.733,P ＜ 0.001).ROC-curve analysis demonstrated that LTA (area under the curve [AUC]:0.677; 95％ confidence interval [CI]:0.643-0.710; P =0.0009),and mTEG (AUC:0.684; 95％ CI:0.650-0.716; P =0.0001) had moderate ability to discriminate between patients with and without MACE.MACE occurred more frequently in patients with high on-treatment platelet reactivity (HPR) when assessed by LTA (7.4％ vs.2.7％; P ＜ 0.001),and by TEG (6.7％ vs.2.6％; P ＜ 0.001).Kaplan-Meier analysis demonstrated that HPR based on the LTA and mTEG was associated with almost 3-fold increased risk of MACE at 1-year follow-up.Conclusions:The correlation between LTA and mTEG is relatively high in Chinese patients.HPR measured by LTA and mTEG were significantly associated with MACE in Chinese patients undergoing PCI.
文摘BACKGROUND Hemostasis of patients suffering from liver cirrhosis is challenging due to both,pro-and anticoagulatory disorders leading to hemostatic alterations with distinct abnormalities of coagulation.Pathological changes in conventional coagulation analysis and platelet count are common manifestations of decreased liver synthesis of coagulation factors and reduced platelet count in these patients.However,conventional coagulation analysis and platelet count do not reflect invivo coagulation status or platelet function.The purpose of this present observational study was therefore to assess the haemostatic profile including plasmatic coagulation using thrombelastometry and impedance aggregometry for platelet function in patients suffering from liver cirrhosis.AIM To assess the hemostatic profile of cirrhotic patients according to model for endstage liver disease(MELD)score.METHODS Our study included both in-and outpatients suffering from liver cirrhosis attending the out-and inpatient care of the department of hepatology.Demographic and biochemical data as well as medical history including cause of liver cirrhosis,end stage kidney failure and medication with anticoagulants were recorded.To assess the hemostatic profile,platelet function was analyzed by multiple electrode aggregometry(MEA)using Multiplate^■(ADP-,ASPI-and TRAP-test)and thrombelastometry using ROTEM^■(EXTEM,INTEM,FIBTEM).Data were compared using Mann-Whitney U-or χ^2-test.Spearman correlation was performed to analyze the association between MELD Score and results of thrombelastometry and MEA.RESULTS A total of 68 patients attending the out-and inpatient care suffering from liver cirrhosis were screened.Of these,50 patients were included and assigned to groups according to MELD score 6 to 11(n=25)or≥17(n=25).Baseline patient characteristics revealed significant differences for MELD score(8 vs 22,P<0.0001)and underlying laboratory parameters(international normalized ratio,bilirubine,creatinine)as well as fibrinogen level(275 mg/dL vs 209 mg/dL,
文摘Background:High on-treatment platelet reactivity (HTPR) has been suggested as a risk factor for patients with ischemic vascular disease.We explored a predictive model of platelet reactivity to clopidogrel and the relationship with clinical outcomes.Methods:A total of 441 patients were included.Platelet reactivity was measured by light transmittance aggregometry after receiving dual antiplatelet therapy.HTPR was defined by the consensus cutoff of maximal platelet aggregation >46% by light transmittance aggregometry.CYP2C19 loss-of-function polymorphisms were identified by DNA microarray analysis.The data were compared by binary logistic regression to find the risk factors.The primary endpoint was major adverse clinical events (MACEs),and patients were followed for a median time of 29 months.Survival curves were constructed with Kaplan-Meier estimates and compared by logrank tests between the patients with HTPR and non-HTPR.Results:The rate of HTPR was 17.2%.Logistic regression identified the following predictors of HTPR:age,therapy regimen,body mass index,diabetes history,CYP2C19^*2,or CYP2C19^*3 variant.The area under the curve of receiver operating characteristic for the HTPR predictive model was 0.793 (95% confidence interval:0.738–0.848).Kaplan-Meier analysis showed that patients with HTPR had a higher incidence of MACE than those with non-HTPR (21.1% vs.9.9%;χ^2 = 7.572,P = 0.010).Conclusions:Our results suggest that advanced age,higher body mass index,treatment with regular dual antiplatelet therapy,diabetes,and CYP2C19^*2 or CYP2C19^*3 carriers are significantly associated with HTPR to clopidogrel.The predictive model of HTPR has useful discrimination and good calibration and may predict long-term MACE.
文摘Given the broad application of aspirin as antiplatelet drug, availability of standardized methodology to assess potential interaction with any co-medication on platelet aggregation is desired. We characterized the effect of aspirin (ASA) therapy on collagen-induced platelet aggregation in whole blood to define such methodology. Collagen-induced platelet whole blood aggregation was assessed in 6 healthy male volunteers on 2 occasions (Day 1, Day 7) using the Chronolog aggregometer. From Day 2 up to Day 7, subjects received a daily oral dose of 75 mg ASA. The relationship between collagen dose and platelet aggregation response was assessed. On Day 1, maximal aggregation was observed at 1 μg/mL collagen (15.3 ± 4.6 Ω) and higher. Reproducible results were obtained without any indication of intra-subject fluctuations. ASA treatment decreased maximal aggregation by 80% and 38% at 0.5 and 2.0 μg/mL collagen, respectively. Power calculations were performed based on the observed intra-subject variability and demonstrated minimal sample sizes of 9 - 11 subjects for future cross-over ASA-drug interaction studies exploring effects on platelet aggregation, which demonstrates that the proposed collagen-induced ex vivo whole blood platelet aggregation is a feasible methodology to evaluate ASA-drug interactions in healthy volunteers.
基金Beijing Higher Education Young Elite Teacher Project(Grant No.YETP0064)from Beijing Municipal Education Commission
文摘Various platelet function tests are currently used to identify responsiveness to antiplatelet therapy. 176 ACS patients were enrolled and Linear regression and Kappa consistency analysis showed there was a significant but moderate correlation between platelet inhibition rate and a significant but fair agreement between high clopidogrel on-treatment platelet reactivity tested by light transmission aggregometry and thrombelastography.
