Monitoring the hemostasis with rotation thromboelastometry in patients with acute STEMI on dual antiplatelet therapy: First experiences.

Rotation thromboelastometry (ROTEM) is a viscoelastometric point-of-care-test for the complex evaluation of changes in hemostasis, performed in whole blood. However, no prospective study evaluating the efficacy of the antiplatelet therapy using ROTEM was performed.Fifty-six patients (34 men, 22 women, mean age 67.75 years, and age range 34-88 years) with acute ST-elevation myocardial infarction (STEMI), treated with dual antiplatelet therapy, undergoing urgent coronary angiography and percutaneous coronary intervention (PCI) of culprit coronary lesion were included. Three blood samples were taken (sample 1 taken before the urgent coronary angiography, sample 2 in 24 hours after the admission, and sample 3 in 30 days after acute STEMI). Twenty-one healthy blood donors (17 men, 4 women, mean age 50.38 years, and age range 40-74 years) were recruited as the control group. Blood samples were tested with ROTEM Gamma (Pentapharm GmbH, Munich, Germany) and light transmission aggregometry (LTA).Clotting time (CT) was significantly prolonged and maximum clot firmness (MCF) was significantly higher in patients compared to controls. Mean platelet aggregation after the induction with arachidonic acid (33.2% vs 74.6% in sample 1 and 21.1% vs 74.6% in sample 2), as well as adenosine diphosphate (51.4% vs 72.7% in sample 1 and 37.1% vs 72.7% in sample 2), were significantly lower in patients with acute STEMI.Significantly prolonged CT and increased MCF was found in patients with acute STEMI. This study confirmed the ability of ROTEM to identify changes in hemostasis in ACS patients on antithrombotic therapy.

Monitoring of Hemostasis and Management of Anticoagulant Thromboprophylaxis in Pregnant Women with Increased Risk of Fetal Loss.

Physiological prothrombotic changes during pregnancy and the postpartum period, along with other preexisting maternal risk factors, increase the risk of both venous thromboembolism (VTE) and adverse pregnancy outcomes. Pregnancy complications that develop due to placental insufficiency as a result of inappropriate activation of coagulation are present in more than 5% of pregnancies and can contribute to significant maternal morbidity and mortality. Therefore, anticoagulant prophylaxis in women with congenital and acquired thrombophilic conditions should be actively considered. According to the Guidelines of American College of Chest Physicians, the use of low-molecular-weight heparin is suggested for prophylaxis of VTE and pregnancy complications in high-risk pregnant women. However, personalized refinements of such thromboprophylaxis remains unspecified, despite the necessity of better targeted recommendations for life-threatening conditions. We, therefore, review the possibilities of longitudinal monitoring and comprehensive assessment of changes in hemostasis in the group of high-risk pregnant women, which can then be used for early prediction and individualization of the optimal anticoagulant thromboprophylaxis of pregnancy complications. Simultaneously, we present our single-center experience with such monitoring and our first series of results.

Ticagrelor: a safe and effective approach for overcoming clopidogrel resistance in patients with stent thrombosis?

Stent thrombosis is a morbid complication following percutaneous coronary intervention (PCI). Dual antiplatelet therapy significantly reduces stent thrombosis risk. However, the antiplatelet response to clopidogrel - the most frequently used ADP receptor antagonist in post-PCI patients - varies among individuals. High on-treatment platelet reactivity was repeatedly associated with the risk of stent thrombosis. Ticagrelor is a novel ADP receptor blocker that has shown greater, more rapid and more consistent platelet inhibition than clopidogrel. This agent offers a unique mechanism of action, no relevant pharmacological interactions, consistent platelet inhibition, and a good safety profile. This article reviews the prospective use of ticagrelor in the treatment of stent thrombosis in acute coronary syndrome patients undergoing PCI of culprit coronary lesion.

Clopidogrel resistance in diabetic patient with acute myocardial infarction due to stent thrombosis.

Stent thrombosis is a morbid complication after percutaneous coronary intervention. Dual antiplatelet therapy significantly reduces stent thrombosis risk and forms currently the basis in acute ST elevation myocardial infarction pharmacologic treatment. The introduction of clopidogrel has made a major advance in the acute coronary syndrome treatment. However, there is growing evidence about failure in antiplatelet response after clopidogrel, which may lead to subsequent risk of future thrombotic events. The antiplatelet inhibitory effect of clopidogrel varies widely among individuals. High on-treatment platelet reactivity has been repeatedly associated with a hazard for cardiovascular events, including stent thrombosis. Laboratory monitoring of antiplatelet therapy efficacy may help identify patients with insufficient antiplatelet response. Prasugrel therapy was repeatedly described as an effective method to overcome clopidogrel resistance. We report a case of diabetic patient in whom myocardial reinfarction due to stent thrombosis developed. Clopidogrel resistance was detected in this patient using light transmission aggregometry and vasodilator-stimulated phosphoprotein phosphorylation assessment. After prasugrel administration, no other ischemic event occurred, and patient was released to outpatient care in good general condition.