Platelet function tests and Chinese medicines with antiplatelet function:a review / 中国中药杂志

Platelet function tests have been increasingly used to assist in the diagnosis of platelet disorders and prethrombotic state, monitoring of the efficacy of antiplatelet therapies, and personalized treatment. On the basis of light transmission aggregometry, new methods for platelet function test have been developed successively. At present, the research and development of platelet function detector is in its infancy in China. The active constituents of antiplatelet Chinese medicines can be classified into terpenoids, flavonoids, saponins, organic acids, lignans, diketones, volatile oils, and stilbenes. The results of dose-antiplatelet effect relationship of Chinese medicines and the active constituents showed that the effective concentration of the extracts or monomers of Chinese medicines was at micromolar level(μmol·L~(-1)), among which salvianolic acid B and ginkgolide K, ginkgolide B, and ginkgolide A had the strongest antiplatelet effect. These results suggest that the antiplatelet effect of Chinese medicine may be weaker than that of chemical drugs and biological products. Therefore, it is necessary to explore the structure-activity relationship of the active constituents in existing Chinese medicines and further improve their efficacy through structure modification. The antiplatelet effect of Chinese medicines and the constituents involves multiple pathways and multiple targets. These research results provide a reference for clinical application of them. However, there is still a lack of large-scale multi-center clinical trials to confirm the efficacy and safety of them. The regularity of the relationship between the structures of various constituents and their corresponding functions is still unknown and the relevant signal transduction pathways and structure-activity relationship need to be further studied. This paper summarized and analyzed the determination methods of platelet functions and the research results of antiplatelet Chinese medicines, which is of reference value for the research of effective and safe antiplatelet Chinese medicines.

The effect of diclofenac on bleeding, platelet function, and consumption of opioids following cardiac surgery

Abstract Objective: To establish whether the use of diclofenac reduces the administration of opioids and how it affects bleeding and platelet function after the coronary artery bypass grafting (CABG) surgery with use of cardiopulmonary bypass (CPB). Methods: A total of 72 patients undergoing CABG surgery were included in this retrospective randomized study and divided into two groups (34 patients received diclofenac and the control group of 38 patients did not). For postoperative analgesia, both groups were prescribed opioids (piritramide). The primary endpoint was to establish the consumption of opioids. The secondary endpoint was to determine bleeding and the function of platelets 20 hours after the surgery. Results: The consumption of piritramide (diclofenac group 26±8 mg vs. control group 28±8 mg), the blood loss, and the function of platelets did not significantly differ between the groups within 20 hours after surgery. C-reactive protein (CRP) was statistically significantly lower in the diclofenac group than in the control group (33±15 mg/L vs. 46±22 mg/L, respectively, P<0.05). Conclusion: The study concluded that patients administered with diclofenac after the heart surgery did not consume less opioid analgesics and did not exhibit less symptoms linked to the consumption of opioids. Diclofenac in clinically administered doses does not interfere with the function of platelets and does not cause increased bleeding. Lower CRP in the diclofenac group may indicate a reduced inflammatory response after CPB. Therefore, diclofenac could be safe for use in patients undergoing CABG surgery but its value in reducing opioid consumption should be questioned.

Variability of Platelet Reactivity on Antiplatelet Therapy in Neurointervention Procedure

As more intracranial aneurysms and other cerebrovascular pathologies are treated with neurointervention procedure, thromboembolic events that frequently lead to serious neurological deficit or fatal outcomes are increasing. In order to prevent the thromboembolic events, antiplatelet therapy is used in most procedures including coil embolization, stenting, and flow diversion. However, because of variable individual pharmacodynamics responses to antiplatelet drugs, especially clopidogrel, it is difficult for clinicians to select the adequate antiplatelet regimen and its optimal dose. This article reviews the neurointervention literature related to antiplatelet therapy and suggests a strategy for tailoring antiplatelet therapy in individual patients undergoing neurointervention based on the results of platelet function testing.

Temporal Variability of Platelet Reactivity in Patients Treated with Clopidogrel or Ticagrelor

BACKGROUND AND OBJECTIVES: The degree of antiplatelet response to P2Y12 inhibitors has been associated with clinical outcomes. The aim of this study was to test the variability of platelet reactivity over time among patients treated with clopidogrel or ticagrelor. METHODS: A single-center cohort of acute coronary syndrome patients that underwent percutaneous coronary intervention (PCI) was analyzed. Platelet reactivity was measured at baseline, 48 hours after PCI, 1 month, and 6 months after clopidogrel (n=79) or ticagrelor (n=93) treatment. High on-treatment platelet reactivity (HPR) was defined as ≥47 U, assessed by multiple electrode platelet aggregometry. RESULTS: Platelet reactivity in the clopidogrel group increased over time, 38.2±21.7 U at 48 hours, 41.4±22.3 U at 1 month, and 44.7±25.5 U at 6 months (p=0.018, 48 hours to 6 months). However, platelet reactivity in the ticagrelor group was not significantly changed, 21.4±12.6 U at 48 hours, 20.0±12.2 U at 1 month, and 22.8±13.8 U at 6 months (p=0.392). A platelet reactivity change over time of more than 20U was found in 67.1% of the patients with clopidogrel group and 34.4% of ticagrelor group (p<0.001). Between 48 hours and 6 months, 43% of patients changed their responder status in the clopidogrel group, and 13% in the ticagrelor group (p<0.001). CONCLUSIONS: Although ticagrelor treatment resulted in less temporal variability of platelet reactivity than clopidogrel treatment in terms of HPR, platelet reactivity varied over time in a significant proportion of patients.

Variability of Platelet Reactivity on Antiplatelet Therapy in Neurointervention Procedure

As more intracranial aneurysms and other cerebrovascular pathologies are treated with neurointervention procedure, thromboembolic events that frequently lead to serious neurological deficit or fatal outcomes are increasing. In order to prevent the thromboembolic events, antiplatelet therapy is used in most procedures including coil embolization, stenting, and flow diversion. However, because of variable individual pharmacodynamics responses to antiplatelet drugs, especially clopidogrel, it is difficult for clinicians to select the adequate antiplatelet regimen and its optimal dose. This article reviews the neurointervention literature related to antiplatelet therapy and suggests a strategy for tailoring antiplatelet therapy in individual patients undergoing neurointervention based on the results of platelet function testing.

Relevant factors of high platelet reactivity during aspirin therapy in patients with ischemic stroke complicated with diabetes / 国际脑血管病杂志

Objective To investigate the changes of platelet reactivity and its influencing factors after aspirin treatment in patients with ischemic stroke complicated with diabetes. Methods From September 2016to December 2017, patients with acute ischemic stroke admitted to the Department of Neurology, Weihai Municipal Hospital within 24 h of onset were enrolled. All patients took aspirin (100 mg/d) within 24 h ofadmission, and after taking the drug (7 ±2 d), the PL-11 platelet function analyzer was used to determine the maximum platelet aggregation ratio (MAR) induced by arachidonic acid (AA). The baseline data of the patients were documented. The factors affecting high platelet reactivity (HPR) were analyzed. Results A total of 398 patients with ischemic stroke were enrolled, including 137 in the diabetes group and 261 in the non-diabetes group. MARAA (43. 45％ ± 14. 11％ vs. 31. 55％ ± 19. 39％; t = 6. 996, P < 0. 001) and the incidence of HPR (34. 3％ vs. 19. 9％; χ2 = 9. 946, P = 0. 002) in the diabetes group were significantly higher than in those in the non-diabetes group. Of the 137 patients with ischemic stroke complicated with diabetes, 47 had HPR. The proportions of patients with hyperlipidemia, previous history of stroke or transient ischemic attack and baseline NIHSS score, HOMA-IR (homeostatis model assessment-insulin resistance),high-sensitivity C-reactive protein, fasting blood glucose, and glycosylated hemoglobin in the HPR group were significantly higher than those in the non-HPR group (all P < 0. 05). Multivariate logistic regression analysis showed that HOMA-IR (odds ratio [OR] 1. 153, 95％ confidence interval [CI] 1. 027-1. 295; P =0. 016), high-sensitivity C-reactive protein (OR 9. 416, 95％ CI 2. 271-39. 049; P = 0. 002), fasting blood glucose (OR 1. 125, 95％ CI 1. 025-1. 235; P = 0. 013), and glycosylated hemoglobin (OR 1. 458, 95％ CI 1. 170-1. 816; P = 0. 001) were the independent risk factors for HPR. Conclusion The platelet reactivity during aspirin therapy in patients with ischemic stroke complicated with diabetes mellitus was high, and platelet activity was associated with multiple mechanisms, such as inflammation, insulin resistance, and hyperglycemia.

Effect of Shenxiong glucose injection on platelet reactivity during aspirin treatment in patients with acute ischemic stroke / 国际脑血管病杂志

Objective To investigate the effect of Shenxiong glucose injection on platelet reactivity during aspirin treatment in patients with acute ischemic stroke.Methods A total of 263 patients with acute ischemic stroke admitted to 12 hospitals from January 2014 to December 2016 were enrolled prospectively.They were randomly divided into aspirin group and aspirin + Shenxiong glucose injection group.The changes of platelet maximum aggregation rate induced by 4 platelet aggregating agents (arachidonic acid,adenosine diphosphate,collagen and platelet activating factor) were detected before and after the treatment.Results There were no significant differences in the demographic data and baseline clinical characteristics between the aspirin group (n =132) and the Shenxiong glucose injection + aspirin group (n =131).At baseline,the maximum aggregation rate of platelet induced by arachidonic acid and platelet activating factor in Shenxiong glucose injection + aspirin group was significantly higher than that in the aspirin group (all P ＜0.05).On the 6th day after treatment,the maximum aggregation rate of platelets induced by the 4 aggregating agents in the Shenxiong glucose injection + aspirin group was significantly lower than that in the aspirin group (all P ＜ 0.001).Conclusion Shenxiong glucose injection had a significant inhibitory effect on platelet reactivity during aspkin treatment in patients with acute ischemic stroke.

Correlation between C3435T polymorphism of ABCB1 gene and response to antiplatelet drugs in Chinese Han patients with ischemic stroke / 国际脑血管病杂志

Objective To investigate the correlation between multidrug resistance gene ABCB1 C3435T polymorphism and antiplatelet drug reactivity in Chinese Han patients with ischemic stroke.Methods Consecutive inpatients with non-cardiogenic embolic ischemic stroke were enrolled.They were divided into a good response to antiplatelet drug group and poor response to antiplatelet drug group according to the results of thrombelastogram.Polymerase chain reaction-restriction fragment length polymorphism technique was use to detect the C3435T polymorphism of ABCB1 gene.Multivariate logistic regression analysis was used to determine the independent risk factors for poor response to antiplatelet drugs in patients with ischemic stroke.Results A total of 260 patients with ischemic stroke were enrolled,including 87 females (33.5％) and 173 males (66.5％).There were 193 patients (74.2％) in the good response group and 67 (25.8％)in the poor response group.The age was younger and male was more common in the good response group,and the proportions of smoking and triacylglycerol level were significantly higher (all P ＜0.05).The frequencies of TT genotype and T allele of the poor response group were significantly higher than those of the good response group (all P ＜ 0.05).Multivariable logistic regression analysis showed that triacylglycerol (odds ratio 1.045,95％ confidence interval 1.011-2.010;P =0.014) and C3435T TT genotype (odds ratio 1.512,95％ confidence interval 1.013-2.256;P=0.043) were the independent risk factors for poor response to antiplatelet drugs after adjusting confounding factors.Conclusion The C3435T TT genotype is an independent risk factor for poor response to antiplatelet drugs in Chinese Han patients with ischemic stroke.

Predictive value of serial platelet function testing on outcome in patients undergoing complex percutaneous coronary intervention / 中华心血管病杂志

Objective@#To observe the predictive value of serial platelet function testing (PFT) on outcome in patients undergoing complex percutaneous coronary intervention (PCI).@*Methods@#Six hundred and two consecutive patients undergoing complex PCI in Anzhen hospital were enrolled during October 2011 to June 2012.Adenosine diphosphate(ADP)-induced platelet aggregation was measured by light transmission aggregometry on the first, sixth and twelfth month after PCI and the mean value was calculated.The cut-off value of high on-treatment platelet reactivity (HTPR) was defined as 40%.The primary endpoint was major adverse cardiovascular and cerebral event (MACCE). Clinical outcomes were analyzed by the Kaplan-Meier method and differences were compared using the log-rank test.Multivariate analyses by Cox proportion hazards regression were applied to identify variables independently associated with the adverse outcomes.@*Results@#Five hundred and eighty-five patients (HTPR, n=285; non-HTPR, n=280) finished the follow-up ((28.47±7.45) months). A total of 33 cases of MACCE were observed during the follow-up, among which 29 cases(8.42%) were in HTPR group and 9 cases (3.21%) in the non-HTPR group.Kaplan-Meier analysis suggested that HTPR was associated with an increased incidence of MACCE (log-rank test, P=0.01). The Cox multivariate analysis indicated that HTPR was an independent risk factor of MACCE (HR=2.69, 95%CI 1.23-5.85, P=0.01) in patients undergoing complex PCI.Incidence of MACCE was similar between HTRP patients receiving standard dual antiplatelet therapy (DAPT) or prolonged DAPT (>12 months).@*Conclusion@#Serial PFT could predict the long-term prognosis of patients underwent complex PCI.

Decreased platelet responsiveness to clopidogrel correlates with CYP2C19 and PON1 polymorphisms in atherosclerotic patients

Clopidogrel and aspirin are the most commonly used medications worldwide for dual antiplatelet therapy after percutaneous coronary intervention. However, clopidogrel hyporesponsiveness related to gene polymorphisms is a concern. Populations with higher degrees of genetic admixture may have increased prevalence of clopidogrel hyporesponsiveness. To assess this, we genotyped CYP2C19, ABCB1, and PON1 in 187 patients who underwent percutaneous coronary intervention. Race was self-defined by patients. We also performed light transmission aggregometry with adenosine diphosphate (ADP) and arachidonic acid during dual antiplatelet therapy. We found a significant difference for presence of the CYP2C19*2 polymorphism between white and non-white patients. Although 7% of patients had platelet resistance to clopidogrel, this did not correlate with any of the tested genetic polymorphisms. We did not find platelet resistance to aspirin in this cohort. Multivariate analysis showed that patients with PON1 and CYP2C19 polymorphisms had higher light transmission after ADP aggregometry than patients with native alleles. There was no preponderance of any race in patients with higher light transmission aggregometry. In brief, PON1 and CYP2C19 polymorphisms were associated with lower clopidogrel responsiveness in this sample. Despite differences in CYP2C19 polymorphisms across white and non-white patients, genetic admixture by itself was not able to identify clopidogrel hyporesponsiveness.

Effects of Platelet Number and Platelet Indices on Platelet Reactivity in Patients Treated with Clopidogrel or Ticagrelor / 대한내과학회지

BACKGROUND/AIMS: Platelet counts and characteristics can influence platelet reactivity during antiplatelet therapy. We compared the effects of both platelet count and indices on platelet reactivity between patients who were treated with either clopodogrel or ticagrelor. METHODS: Patients with coronary artery disease who underwent percutaneous coronary intervention were randomly assigned to either the clopidogrel (n = 63) or ticagrelor (n = 65) groups. Platelet count, platelet indices (including mean platelet volume, platelet distribution width, platelet large cell ratio, and immature platelet fraction), and platelet reactivity were measured before intervention, and 48 hours and 30 days post-intervention. High on-treatment platelet reactivity (HPR) was defined as ≥ 47 unit as assessed by multiple electrode platelet aggregometry. RESULTS: Baseline platelet reactivity was similar between the two groups; however, at 48 hours and 30 days, platelet reactivity was significantly lower in the ticagrelor group than in the clopidogrel group. Platelet count, mean platelet volume, platelet distribution width, platelet large cell ratio, and immature platelet fraction were significantly correlated with platelet reactivity in the clopidogrel group; however, these correlations were attenuated in the ticagrelor group. The use of clopodogrel (hazard ratio [HR] 4.1, 95% confidence interval [CI] 1.4–11.9; p = 0.010) and platelet count (HR 9.7, 95% CI 2.9–32.7; p = 0.001) were independent predictors for 30 day HPR. Platelet count was an independent predictor of HPR in the clopidogrel group but not in the ticagrelor group. CONCLUSIONS: Platelet count and indices are significantly correlated with platelet reactivity. However, antiplatelet treatment with ticagrelor could overcome these associations.

The impact of residual platelet activity and CYP2C19 polymorphism on the prognosis of acute coronary syndrome patients / 中华检验医学杂志

Objective To evaluate the correlation between RPA or the polymorphism of CYP 2C19 and the incidence of ischemic events and the influence on the clinical prognosis .Methods A case-control study was used.A total of 202 patients [male 66%,(63 ±11) years] with ACS on aspirin and clopidogrel treatment were recruited , whose RPA were measured by whole blood aggregometry ( WBA ) , and their CYP2C19 polymorphism were also tested .Their clinical ischemic events were recorded in the mean follow-up period of 16 months.The RPA cut-off values for antiplatelet low-responsiveness were defined by the receiver operator characteristic curve ( ROC); the relationships of clinical outcomes with RPA and CYP 2C19 were assessed by the Kaplan-Meier survival analysis.Results CYP2C19*2 (681G>A) present in 52.5% of recruited patients and*3 (636G>A) present in12.9%.RPA induced by adenosine diphosphate ( ADP) showed significant difference among CYP 2C19*2 or *3 heterozygotes, CYP2C19*2 or *3 homozygotes and noncarriers (χ2 =9.318, P=0.009);whereas, RPA induced by arachidonic acid (AA) (χ2 =2.441, P=0.295) and the incidence of ischemic events (χ2 =0.513, P=0.774) were not.During follow-up, 18 (9%) patients experienced clinical ischemic episodes , and their RPA were higher than patients without ischemic episodes [(8.6 ±4.8) Ωvs (5.2 ±3.7) Ω, P =0.013; (8.6 ±6.8) Ωvs (1.6 ±3.7) Ω, P <0.001].Moreover, employing 6.5 Ω(induced by ADP) and 2.5 Ω(induced by AA) as cutoff values,RPA showed optimal negative predictive values (97%, 96%) and poor positive predictive values (16%,29%).Survival analysis showed, statistically, patients with clopidogrel low-responsiveness had higher riskof ischemic episodes than patients with clopidogrel responsiveness (HR =2.86, χ2 =11.27,P =0.0008);however, patients with aspirin low responsiveness (HR =1.77, χ2 =1.74, P =0.19) or patients withCYP2C19*2 or *3 (HR =0.89, χ2 =0.12, P =0.73) did not.Conclusion Clopidogrel lowresponsiveness is associated with the occurrence of clinical ischemic events ; however, patients withCYP2C19 function reduced genetypes do not show higher risk of ischemic episodes though it presented slighlyhigher RPA.

Four detection methods for antiplatelet function of clopidogrel: A comparative study / 第二军医大学学报

Objective To assess the consistencies of VerifyNow system, thrombelastography (TEG), vasodilator-stimulated phosphoprotein (VASP), and PL-11 platelet analyzer in detecting the antiplatelet function of clopidogrel, and to discuss the clinical application values. Methods Totally 98 consecutive inpatients with ST-segment elevation myocardial infarction (STEMI), non-(NSTEMI), or coronary artery in-stent restenosis (SR) were included in this study. The patients were given a loading dose of 600-mg clopidogrel for 6 hours, 300-mg clopidogrel for at 24 hours, or chronic clopidogrel therapy (75 mg daily for ≥ 7 days) before the procedure. And then the antiplatelet effects were evaluated by VerifyNow, TEG, VASP and PL-11 platelet analyzer simultaneously, with the results of VerifyNow taken as the gold standard and P2Y12 reaction unit (PRU) ≥ 208 taken as high on-clopidogel treatment platelet reactivity (HTPR). Correlation analysis was done for the four methods, and area under ROC curve (AUC) was used to evaluate the value of each method for HTPR. Results The platelet inhibition rate detected by VerifyNow was positively correlated with that by TEG (r = 0. 234, P < 0. 05); by contrast, it was negatively correlated with the platelet reactivity index (PRI) measured by VASP, the maximum platelet aggregation rate (MAR) by PL-11 and the maximum adenosine diphosphate (MA-ADP) by TEG (r = –0. 299, P<0. 01; r = –0. 330, P< 0.05; r = –0. 237, P<0. 05). The PRU values was negatively correlated with the platelet inhibition rate detected by VerifyNow (r = –0.815, P < 0. 01). The area under ROC curve of PL-11 platelet analyzer was the highest (0. 644). Conclusion TEG, VASP, and PL-11 platelet function testing systems all have consistency with the “gold standard” VerifyNow in some extent, with PL-11 platelet analyzer showing the highest sensitivity and specificity.

Evaluation of PL-11 in short-term antiplatelet therapy monitoring / 中华检验医学杂志

Objective To evaluate a new platelet function analyzer PL-11 with three major platelet function methods.Methods A randomized controlled trial was adopted.Totally 20 healthy young students from People's Liberation Army Medical School were enrolled in the study during July and August in 2013.Subjects were treated with aspirin or clopidogrel and the platelet function was measured by using of PL-11,as well as light transmittance aggregometry (LTA),VerifyNow and thromboelastography (TEG).Results When monitor aspirin response,correlations between arachidonic acid (AA) induced PL-11 and other methods were:LTA,0.614; VerifyNow,0.829; TEG,0.697,respectively.Biases between AA induced PL-1 1 and LTA were 1.94％ at baseline and 24.02％ during aspirin treatment.Cut-off value of aspirin response tested with AA induced PL-11 was 33.3％.When monitor clopidogrel response,correlations between adenosine piphosphate (ADP) induced PL-11 and other methods were:LTA,0.767; VerifyNow,0.851; TEG,0.608.Biases between ADP induced PL-11 and LTA were 3.01％ at baseline and 6.56％ during clopidogrel therapy.Cut-off value of clopidogrel response tested with ADP induced PL-1 1 was 66％.Conclusion Results of different platelet function testing methods were not equally effective.PL-11 has a high capability when monitoring short aspirin or clopidogrel response.

Role of platelet function testing in the prevention and treatment of ischemic stroke / 国际脑血管病杂志

Platelet function testing is essential for the prevention and treatment of ischemic stroke.Only simple and convenient method of platelet function testing can become the conventional detection method for patients with ischemic stroke and can be used to the prevention and treatment of ischemic stroke in clinical practice.

Randomized Comparison of the Platelet Inhibitory Efficacy between Low Dose Prasugrel and Standard Dose Clopidogrel in Patients Who Underwent Percutaneous Coronary Intervention

BACKGROUND AND OBJECTIVES: Increased bleeding rates with standard dose prasugrel have led to increased questions about the effectiveness and safety of the lower maintenance dose. We compared platelet inhibitory efficacy between low dose prasugrel and standard dose clopidogrel in patients on maintenance dose dual antiplatelet therapy. SUBJECTS AND METHODS: Forty-three patients who underwent percutaneous coronary intervention were randomized to receive 75 mg clopidogrel (n=23) or 5 mg prasugrel (n=20). Another 20 patients were allocated to 10 mg prasugrel as a reference comparison group. All patients (weight, > or =60 kg; age, 235) was significant lower in the 5 mg prasugrel group than that in the 75 mg clopidogrel group (15.0% vs. 56.5%, p=0.010). CONCLUSION: Prasugrel (5 mg) is more potent antiplatelet therapy than 75 mg clopidogrel in non-low body weight and non-elderly patients on a maintenance dose dual antiplatelet therapy.

Lower Loading Dose of Prasugrel Compared with Conventional Loading Doses of Clopidogrel and Prasugrel in Korean Patients Undergoing Elective Coronary Angiography: A Randomized Controlled Study Evaluating Pharmacodynamic Efficacy

BACKGROUND AND OBJECTIVES: Although prasugrel allows for rapid and potent platelet inhibition, the efficacy and safety of lower doses of prasugrel for patients of East Asian ethnicity has not yet been investigated. We compared the effect of a lower loading dose (LD) of prasugrel with conventional LDs of clopidogrel and prasugrel in Korean patients. SUBJECTS AND METHODS: Forty-three Korean patients undergoing coronary angiography were enrolled in the study. Participants were randomly administered LDs of clopidogrel 600 mg, prasugrel 30 mg or prasugrel 60 mg prior to coronary angiography. Platelet reactivity was assessed at baseline and at the time of peak platelet inhibition using light transmission aggregometry (LTA), the VerifyNow assay, and multiple electrode aggregometry. RESULTS: Although baseline platelet reactivity between the groups showed no significant differences, at the time of peak platelet inhibition, the prasugrel 30 mg (18.9+/-10.0%) and 60 mg groups (13.8+/-10.8%) showed significantly more potent platelet inhibition than the clopidogrel 600 mg group (52.9+/-15.8%; p<0.001) by LTA. However, there were no significant differences between the prasugrel 30 mg and 60 mg groups (p=0.549). CONCLUSION: The loading effect of prasugrel 30 mg was more potent than clopidogrel 600 mg and was not significantly different from prasugrel 60 mg.

Several hot topics and thinking about routine examination of domestic coagulation tests / 中华检验医学杂志

The progress on methodology evaluation and quality control of laboratory diagnosis of venous thrombosis and hemophilia and that of platelet function assessment were summarized.Methods to promote the development of routine test of hemorrhagic and thrombotic disorders and to improve the quality of laboratory testing were suggested.

Research advances in monitoring platelet function in patients with coronary artery disease / 中华检验医学杂志

Antiplatelet therapy and stent implantation have been the dominant treatment to reduce the mortality of patients with coronary artery disease.Recently,studies have showed that adverse cardiac events still occur in part of patients with coronary artery disease after the antiplatelet treatment with aspirin and/or clopidogrel.Thus,resistance to aspirin and clopidogrel has attracted increasing attention.It will be great benefit to these patients who were identified resistance and made tailoring antiplatelet therapy So far many platelet function tests has been used in clinical to monitor the reaction of the antiplatelet drugs for prevention and treatment of thrombosis in patients with coronary artery disease.These monitoring tests may be chosen based on different antiplatelet drugs including aspirin,clopidogrel and GP Ⅱ b/Ⅲ a antagonist.The results of antiplatelet drug resistance may be different due to different platelet function methods,thus the related clinical adverse events needs further verification.

PFA-100: una nueva prueba de funciónplaquetaria sustituta del tiempo de sangría / PFA-100: a platelet function test as a substitute for the bleeding time

Resumen: El PFA-100, por Platelet Function Analyzer (Analizador de Función Plaquetaria) es una nueva herramienta para la investigación de la hemostasia primaria, descrita e introducida al laboratorio clíni-co a partir de 1995, actualmente disponible en el medio. El PFA-100 se fundamenta en un instrumento (PFA-100 o PFA-200), que simula la circulación sanguínea, y dos cartuchos de reactivos que contienen membranas impregnadas de colágeno/epinefrina y colágeno/ADP, que simulan los tejidos. Desde el punto de vista técnico, la prueba es equivalente in vitro al tiempo de sangría tradicional in vivo, por lo que también se la conoce como tiempo de sangría in vitro. El PFA-100 se puede utilizar en diferentes situaciones medicas: (1) como una prueba sustituta del tiempo de sangría, (2) como una prueba tamiz de una disfunción plaquetaria ya sea congénita o adquirida, (3) como una prueba de monitoreo en el manejo de enfermedades congénitas de la función plaquetaria y en particular de la enfermedad de von Willebrand, (4) como una prueba de diagnóstico y control en el caso de la resistencia a la aspirina y la resistencia al clopidogrel, (5) como una prueba de control de calidad en el banco de sangre; y (6) como una prueba médico-legal en el diagnóstico diferencial de las enfermedades hematológicas con manifestaciones hemorrágicas y el maltrato infantil, entre otras muchas indicaciones El tiempo de sangría ha pasado a ser una prueba obsoleta, no recomendada en la práctica clínica por organiza-ciones como el Colegio Americano de Patología (CAP) y la Sociedad Americana de Patología Clínica (ASCP), y como tal debería desaparecer de los portafolios de servicio de los laboratorios clínicos...

Summary: Platelet Function Analyzer (PFA) is a new tool for the investigation of primary hemostasis. It was introduced in the clinical laboratory since 1995 and is currently available as diagnostic tests. The PFA is based on an instrument (PFA-100 and PFA-200), which simulates the blood flow, and two cartridges containing membranes impregnated with collagen/epinephrine and collagen/ADP, which simulate the tissue. From a technical point of view, the test is an In vitro equivalent to In vivo test known as bleeding time. The PFA-100 can be used in different medical situations: (1) as a screening test of platelet dysfunction either congenital or acquired, (2) as a diagnostic test in the case of aspirin and 512Germán Campuzano Maya, MDMedicina & LaboratorioVolumen 19, Números 11-12, 2013.clopidogrel resistance, (3) as a screening test in the case of follow-up of patients with von Willebrand disease undergoing treatment with desmopressin, (4) as quality control test in blood bank, in the case of platelet transfusions; and (5) as a legal-medical test in the differential diagnosis of hematological diseases with mucocutaneous manifestations and child abuse, among many other indications. The bleeding time has become an outdated test, it is not recommended in clinical practice by organizations as the College of American Pathologists and the American Society for Clinical Pathology, and should be removed from clinical laboratories services...