At the same time, bleeding and blood transfusions, which are associated with increased mortality risk, remain a frequent complication in patients with NSTE ACS. thus do not impact other platelet activation pathways, such as the one triggered by interaction of thrombin with protease-activated receptor (PAR)-1, thereby exposing patients Zidebactam to continued accumulation of thrombotic events. Conclusion These considerations suggest that novel therapies with a different mechanism of action, when used in combination with current antiplatelet agents, may provide more comprehensive inhibition of platelet activation and additional reductions in morbidity and mortality, potentially without incremental bleeding risk. valuevalueacute coronary syndromes, aspirin, cardiovascular, myocardial infarction, non-ST-segment elevation, percutaneous coronary intervention, Thrombolysis in Myocardial Infarction a Clopidogrel loading dose = 300?mg; maintenance dose = 75?mg/d bMajor bleeding was defined as substantially disabling bleeding, intraocular bleeding leading to the loss of vision, or bleeding necessitating the transfusion of at least 2 units of blood cPrasugrel loading dose = 60?mg; maintenance dose = 10?mg/d. Clopidogrel loading dose = 300?mg maintenance dose = 75?mg/d dTIMI major bleeding eTicagrelor loading dose = 180?mg; maintenance dose = 90?mg twice daily. Clopidogrel loading dose = 300C600?mg; maintenance dose = 75?mg/day fMajor bleeding was defined as bleeding that led to clinically significant disability (e.g., intraocular bleeding with permanent vision loss) or bleeding either associated with a drop in the hemoglobin level of at least 3.0?g per deciliter but less than 5.0?g per deciliter or requiring transfusion of 2 to 3 3 units of red cell Several studies have documented variable responsiveness of platelets to therapy with clopidogrel [29]. Although a standardized definition and methodology for assessment of responsiveness to antiplatelet therapy has not been established, sufficient evidence supports the Zidebactam concept that persistence of enhanced platelet reactivity despite the use of clopidogrel is clinically relevant [30C33]. A correlation between low level of inhibition of ADP-induced platelet aggregation in response to clopidogrel and recurrence of ischemic events has been documented in several studies in patients with ACS and those undergoing PCI [31C33]. Although the mechanisms responsible for the variability and low responsiveness to clopidogrel have not been fully elucidated, recent analyses suggest that genetic polymorphisms of the cytochrome P (CYP) 450 enzymes can significantly modulate individual response to clopidogrel and are important determinants of prognosis [34C36]. A study of patients with acute MI treated with clopidogrel demonstrated that the carriers of the CYP2C19*2 allelic variant (CYP2C19) had a significantly higher rate of ischemic events (death, non-fatal MI, or urgent revascularization) than non-carriers (10.9 events per 100 patient-years vs 2.9 events per 100 patient-years, respectively; adjusted hazard ratio: 5.38, for trend = 0.0009) [62]. Reproduced with permission Use of antiplatelet therapy in clinical practice: insights from registries Continuous evaluations of management of patients with NSTE ACS in the United States in the CRUSADE registry from 2002 to 2004 have demonstrated significant improvements in use of medications both in the acute setting (antiplatelet agents, anticoagulants, glycoprotein IIb/IIIa receptor inhibitors and beta-blockers) and in the discharge setting (antiplatelet agents, lipid-lowering agents, angiotensin-converting enzyme inhibitors) [11]. However, use of many Rabbit Polyclonal to SFRS17A therapies was suboptimal, and there was a clear need for greater implementation of the ACC/AHA guidelines recommendations [11]. CRUSADE has also documented significantly lower use of evidence-based therapies in the elderly, women, minority populations, and patients without private insurance [68C70]. More recently, the ACTION registry reported that clopidogrel was used in only 60% of patients with NSTEMI in the acute setting and in 74% of patients with NSTEMI at discharge during 2008 [71]. Differences in clopidogrel utilization have also been noted based on management strategy [70, 71]. The latest available data from ACTION for the year 2008 document that clopidogrel was used among patients with NSTEMI at the time of hospital discharge in 97% of those who underwent PCI, but in only 55% of those who were medically managed, and in only 28% of those who underwent CABG, even though they were admitted to the hospital with an ACS [71]. Importantly, lack of early clopidogrel use was associated with significantly higher Zidebactam in-hospital mortality and other adverse outcomes compared with early initiation of clopidogrel in CRUSADE (Fig.?3) [9]. Open in a.
