Aspirin is often combined with a P2Y12 receptor antagonist (clopidogrel, prasugrel, or ticagrelor) for dual antiplatelet therapy (DAPT) after PCI or ACS. 3,4 Aspirin monotherapy or DAPT may also be used to prevent major adverse cardiovascular events for patients with peripheral artery disease. 5 Oral anticoagulants, including warfarin and the direct oral anticoagulants (DOACs), are used for a wide range of thrombotic disorders, most commonly to prevent stroke and systemic embolism associated with AF and to prevent or treat venous thromboembolism (VTE).
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What is the antiplatelet strategy in aspirin failure?
Antiplatelet Strategy in Aspirin Failure. A meta-analysis of four relevant cohort and randomized controlled studies (enrolling 4,491 patients) found that adding an antiplatelet agent to aspirin monotherapy, or switching to another antiplatelet therapy, was associated with a 30% reduced risk of recurrent ischemic or hemorrhagic stroke (HR,...
Should we change the antiplatelet regimen in TIA/stroke patients on aspirin monotherapy?
These results suggest a benefit of changing the antiplatelet regimen in patients with ischemic stroke or TIA while on aspirin monotherapy. A randomized controlled trial of different antiplatelet strategies in TIA/stroke patients with “aspirin failure” is indicated prior to guideline change.
Are there evidence-based recommendations for antiplatelet and anticoagulation management in cardiac surgery?
This document presents a professional view of evidence-based recommendations around the issues of antiplatelet and anticoagulation management in cardiac surgery. It was prepared by the Audit and Guidelines Committee of the European Association for Cardio-Thoracic Surgery (EACTS).
What is the mechanism of action of aspirin on platelets?
Aspirin is an approximately 150- to 200-fold more potent inhibitor of the (constitutive) isoform of the platelet enzyme (COX-1) than the (inducible) isoform (COX-2) which is expressed by cytokines, inflammatory stimuli, and some growth factors.
When do you add aspirin to anticoagulation?
Adding aspirin (ASA) to a DOAC is often appropriate after acute coronary syndromes or percutaneous coronary intervention. However, many patients receive oral anticoagulation and ASA without a clear need for combination therapy.
Can anticoagulants and antiplatelets be taken together?
Following percutaneous coronary interventions, antiplatelet drugs are required to prevent in-stent thrombosis. In-stent thrombosis has a mortality of 50–70%,3 so the use of one or two antiplatelet drugs together with an anticoagulant is often required. However, such combinations increase the risk of bleeding.
How many hours should you wait before beginning administration of any anticoagulant or antiplatelet medications?
There is no reversal agent for these medications. We do not hold any of these medications before low-risk procedures, but we do wait 4 hours after discontinuation before beginning moderate- and high-risk procedures [10]. We resume these medications within 1 hour after all procedures.
When do you use anticoagulant and antiplatelet?
There are two classes of antithrombotic drugs: anticoagulants and antiplatelet drugs. Anticoagulants slow down clotting, thereby reducing fibrin formation and preventing clots from forming and growing. Antiplatelet agents prevent platelets from clumping and also prevent clots from forming and growing.
Can you give Plavix and heparin together?
There were no adverse events that could be related to clopidogrel. In conclusion, under the study conditions, no interactions between clopidogrel and heparin were observed.
Can you give clopidogrel and apixaban together?
“Our findings show that the combination of apixaban and a drug such as clopidogrel—without aspirin—is the safest treatment regimen for this difficult-to-treat group of patients, without significantly increasing ischemic events such as heart attacks, strokes and blood clots.
What is bridging anticoagulation?
'Bridging” is a term that refers to the use of short-acting anticoagulants (heparin or LMWH) for a period of time during interruption of warfarin therapy when the INR is not within a therapeutic range. There is no established single bridging regimen.
When do you start antiplatelets after surgery?
Dual antiplatelet therapy is recommended during the two weeks after simple dilatation, six weeks after bare-metal stents, and at least 12 months after drug-eluting stents. All elective operations should be postponed beyond these delays.
When do you hold heparin for low platelets?
The guidelines call for a full dose of enoxaparin for the treatment of cancer-associated venous thromboembolism when a patient's platelet count is more than 50,000/mcL, a half dose when the platelet count is between 25,000/mcL and 50,000/mcL, and to hold therapy temporarily when the platelet count is less than 25,000/ ...
When is antiplatelet therapy indicated?
Antiplatelet therapy is indicated in patients with PAD to reduce the risk of major cardiovascular events. However, remains an open issue why PAD represents an atherosclerotic clinical model where aspirin, differently from coronary heart disease, is less effective in reducing atherosclerotic progression.
When are antiplatelet drugs used?
Antiplatelet drugs may be used to: Prevent heart attack or stroke for those with PAD. Clopidogrel (Plavix, generic) may be used in place of aspirin for people who have narrowing of the coronary arteries or who have had a stent inserted.
What is the difference between antiplatelets and anticoagulants?
There are different types of blood thinners: Anticoagulants, such as heparin or warfarin (also called Coumadin), slow down your body's process of making clots. Antiplatelets, such as aspirin and clopidogrel, prevent blood cells called platelets from clumping together to form a clot.
Does aspirin reduce risk of cardiovascular events?
A meta-analysis of five relevant cohort and randomized controlled studies (enrolling 8,723 patients) found that adding an antiplatelet agent to aspirin monotherapy, or switching to another antiplatelet therapy, was associated with a 32% reduced risk of major adverse cardiovascular events (hazard ratio [HR], 0.68; 95% confidence interval [CI], 0.54-0.85).
Does aspirin reduce the risk of stroke?
A meta-analysis of four relevant cohort and randomized controlled studies (enrolling 4,491 patients) found that adding an antiplatelet agent to aspirin monotherapy, or switching to another antiplatelet therapy, was associated with a 30% reduced risk of recurrent ischemic or hemorrhagic stroke (HR, 0.70; 95% CI, 0.54-0.92).
Is 100 mg of aspirin safe for thrombus formation?
While 100 mg/day is sufficient for prevention of thrombus formation in the coronary circulation, higher doses may be required for the prevention of vascular events in the cerebral and peripheral circulation. However, any effective antiplatelet dose of aspirin is associated with an increased risk of bleeding.
Is aspirin an anti-inflammatory?
This explains the different dosage requirements of aspirin as an antithrombotic ( COX-1) and an anti-inflammatory drug ( COX-2), respectively. Aspirin is the "gold standard" antiplatelet agent for prevention of arterial thromboses. The optimum dose of aspirin as an antithrombotic drug can differ in different organ circulations.
Is aspirin a cytokine?
Aspirin is an approximately 150- to 200-fold more potent inhibitor of the (constitutive) isoform of the platelet enzyme (COX-1) than the (inducible) isoform (COX-2) which is expressed by cytokines, inflammatory stimuli, and some growth factors.
Does aspirin inhibit platelet function?
The antithrombotic action of aspirin (acetylsalicylic acid) is due to inhibition of platelet function by acetylation of the platelet cyclooxygenase (COX) at the functionally important amino acid serine529. This prevents the access of the substrate (arachidonic aid) to the catalytic site of the enzyme at tyrosine385 and results in an irreversible ...
What are antiplatelet and anticoagulant?
Antithrombotic agents, consisting of antiplatelet and anticoagulant medications, are some of the most commonly prescribed medications. They are currently used by millions of Americans to prevent thrombotic complications in a wide variety of cardiovascular conditions. 1 When combined, these medications increase the risk of significant bleeding complications. Recent studies have compared different combinations of antiplatelet and anticoagulant medications for a variety of cardiovascular conditions. Applying the findings from these trials will help individual patients and their health care providers balance potential benefits and risks when selecting appropriate antithrombotic regimens.
How long does it take for aspirin to reduce ischemic events?
Equally important, the risk reduction in cardiovascular death, MI, stroke, and stent thrombosis associated with aspirin use is concentrated in the first 30 days but does not extend beyond that time point. 13 In fact, there is a nearly equal increased risk of ischemic events and decreased risk of bleeding events in the first 30 days after PCI or ACS. But after those initial 30 days, the increased risk of bleeding associated with aspirin use persists, whereas the ischemic risk is equal with and without aspirin therapy.
What is the largest trial to compare anticoagulant dosages?
The largest trial comparing different oral anticoagulant dosages and number of antithrombotic medications is the AUGUSTUS trial. 11 This trial used a 2 × 2 factorial design to compare treatment dosages of both warfarin and apixaban and to compare DAPT to clopidogrel alone in patients with AF who had undergone PCI or experienced an ACS. The findings suggest a marked reduction in major bleeding associated with the use of apixaban as compared with warfarin and with omission of aspirin therapy. Collectively, when the warfarin–clopidogrel–aspirin triple therapy combination was compared with the apixaban–clopidogrel double therapy combination, only 9 patients needed to be treated with the apixaban–clopidogrel regimen to avoid 1 major or clinically relevant nonmajor bleeding event. Of note, not all trials used full treatment dosages of anticoagulants, which limits the ability to compare the impact of different anticoagulant drugs and dosage combinations with the inclusion or omission of aspirin therapy on bleeding outcomes. Although some suggest that clinicians select the lowest possible anticoagulant dosage when combining with antiplatelet therapy, others favor use of an anticoagulant dosage that has been proven effective for stroke prevention in AF.
How long should DAPT be for PCI?
Independent of the need for ongoing anticoagulant therapy, recent studies have suggested that shorter courses of DAPT (sometimes ≤3 months) may be appropriate for many patients undergoing PCI. 14,15 Therefore, many cardiovascular specialists, including interventional cardiologists, are recommending shorter courses of DAPT for patients after PCI or an ACS if they are taking concurrent anticoagulant medications ( Figure 1 ). In fact, recent guidelines and expert consensus documents recommend shorter courses of triple therapy for most of these patients. 16-18 This recommendation is supported by 2 recent meta-analyses showing lower rates of bleeding when dual therapy (an anticoagulant plus P2Y12 inhibitor) rather than triple therapy is used. 19,20 This is particularly true for the combination of a DOAC plus P2Y12 inhibitor and is similar in both stable CAD and ACS. Fortunately, the meta-analyses have also demonstrated no significant increased risk in all-cause mortality, cardiovascular mortality, MI, stent thrombosis, major adverse cardiac events, or stroke.
What is aspirin used for?
Aspirin therapy has been used for decades to prevent and treat cardiovascular disease, including myocardial infarction (MI) and ischemic stroke. This usage is based, in part, on a series of studies published before 2005 demonstrating reductions in MI risk. 2 Daily aspirin therapy was widely recommended in both clinical guidelines and the lay media, leading to broad application both with and without health care provider involvement. Aspirin is often combined with a P2Y12 receptor antagonist (clopidogrel, prasugrel, or ticagrelor) for dual antiplatelet therapy (DAPT) after PCI or ACS. 3,4 Aspirin monotherapy or DAPT may also be used to prevent major adverse cardiovascular events for patients with peripheral artery disease. 5 Oral anticoagulants, including warfarin and the direct oral anticoagulants (DOACs), are used for a wide range of thrombotic disorders, most commonly to prevent stroke and systemic embolism associated with AF and to prevent or treat venous thromboembolism (VTE).
What is anticoagulant used for?
Anticoagulant use for indications other than AF, severe renal insufficiency, prior intracranial bleed, recent or planned coronary artery bypass graft surgery, or ongoing bleeding. Mechanical heart valve, moderate to severe mitral stenosis, and end-stage renal disease.
Can anticoagulants cause bleeding?
Third, patients who need combined use of anticoagulants and antiplatelet medications are at increased risk for upper gastrointestinal (GI) bleeding. Proton pump inhibitors (PPIs) can be highly effective at reducing this risk, but they are often underused. 34-37 Data supporting reductions in hospitalizations for upper GI bleed exist for patients taking anticoagulants and concurrent aspirin, P2Y12 inhibitors, and nonsteroidal anti-inflammatory medications. 34,35 Although the primary bleeding outcome was not significantly reduced in the PPI arm of the COMPASS trial (HR 0.88; 95% CI, 0.67-1.15), there was a reduction in overt GI bleeding events (HR 0.52; 95% CI, 0.28-0.94). 36 The low dosage of anticoagulant used in this study may have affected the overall bleeding rates. However, concerns remain regarding long-term PPI use and risk of cardiovascular disease, renal insufficiency, Clostridium difficile infection, and fracture risk. 38 Guidelines from both North America and Europe recommend PPI use for patients taking combined anticoagulant–anticoagulant therapy given that the reduction in elevated GI bleeding risk probably outweighs any potential drug-related adverse event risk. 17,39 It is also important to address PPI deprescribing once the bleeding risk has been mitigated (eg, transition to anticoagulation monotherapy).
What is the trial of low-intensity oral anticoagulation with warfarin and low-dose as?
Thrombosis prevention trial: randomised trial of low-intensity oral anticoagulation with warfarin and low-dose aspirin in the primary prevention of ischaemic heart disease in men at increased risk. The Medical Research Council’s General Practice Research Framework
What are the effects of platelets on tumors?
Signals from platelets have also been suggested to confer epigenetic alterations, including upregulating oncoproteins in circulating tumor cells, and secretion of potent growth factors may play roles in promoting mitogenesis, angiogenesis, and metastatic outgrowth.
Is Add-Aspirin a placebo controlled trial?
ADD-ASPIRIN: a phase III, double-blind, placebo controlled, randomised trial assessing the effects of aspirin on disease recurrence and survival after primary therapy in common non- metastatic solid tumours
Do antiplatelets help with cancer?
Platelets have been hypothesized to promote certain neoplastic malignancies; however, antiplatelet drugs are still not part of routine pharmacological cancer prevention and treatment protocols. Paracrine interactions between platelets and cancer cells have been implicated in potentiating the dissemination, survival within the circulation, and extravasation of cancer cells at distant sites of metastasis. Signals from platelets have also been suggested to confer epigenetic alterations, including upregulating oncoproteins in circulating tumor cells, and secretion of potent growth factors may play roles in promoting mitogenesis, angiogenesis, and metastatic outgrowth. Thrombocytosis remains a marker of poor prognosis in patients with solid tumors. Experimental data suggest that lowering of platelet count may reduce tumor growth and metastasis. On the basis of the mechanisms by which platelets could contribute to cancer growth and metastasis, it is conceivable that drugs reducing platelet count or platelet activation might attenuate cancer progression and improve outcomes. We will review select pharmacological approaches that inhibit platelets and may affect cancer development and propagation. We begin by presenting an overview of clinical cancer prevention and outcome studies with low-dose aspirin. We then review current nonclinical development of drugs targeted to platelet binding, activation, and count as potential mitigating agents in cancer.
How long should I take clopidogrel after a stent?
According to the 2016 ACC/AHA Guideline Focused Update on Duration of Dual Antiplatelet Therapy in Patients With Coronary Artery Disease, in patients with SIHD treated with DAPT after DES implantation, P2Y12 inhibitor therapy with clopidogrel should be given for at least 6 months (Class I). The guidelines offer flexibility in treatment duration beyond 6 months. 15 American College of Cardiology and American Heart Association guidelines recommend that elective noncardiac surgery should be delayed 30 days after bare-metal stent (BMS) implantation and optimally 6 months after DES implantation. In patients treated with DAPT after PCI who must undergo surgical procedures that mandate the discontinuation of DAPT, it is recommended that aspirin be continued if possible and the additional agent be restarted as soon as possible after surgery (Class I). DAPT should generally be discontinued 3-7 days prior to elective surgery. The most recent society guidelines are summarized in Table 2.
What is the collaboration of antithrombotic trialists?
Antithrombotic Trialists' Collaboration. Collaborative meta-analysis of randomised trials of antiplatelet therapy for prevention of death, myocardial infarction, and stroke in high risk patients. BMJ 2002;324:71-86.
How long should a patient be on DAPT?
Standard duration of DAPT in patients with SIHD treated with a contemporary DES should be 6 months. Shorter duration (3-6 months) may be reasonable in patients at higher bleeding risk or with a low risk of ischemic events. Prolonged DAPT (>12 months) should be reserved for patients at an increased risk of ischemic events. We recommend an individualized approach to determine the optimal antiplatelet treatment combination for your patients with SIHD who have had PCI.
What drugs block P2Y12?
The thienopyridine and cyclopentyl-triazolo-pyrimidine (CPTP) classes of drugs all block the P2Y12 receptor. Their mechanisms of action, however, differ between drugs. Thienopyridines are irreversible, pro-drugs that inhibit platelet aggregation through P2Y12 adenosine diphosphate (ADP) receptor blockade. 2 Clopidogrel is a pro-drug that must undergo a two-step oxidation to form an active metabolite, whereas prasugrel is a pro-drug that must undergo a one-step oxidation to become an active metabolite. 3 Ticagrelor is an active agent that acts via reversible inhibition of ADP receptors and is part of the CPTP class of drugs. Prasugrel and ticagrelor have approximately double the potency compared with clopidogrel based on inhibition of ADP-mediated platelet aggregation. Due to a high prevalence of high on-treatment platelet reactivity with clopidogrel, selection of antiplatelet agent should be individualized, especially in patients with an increased risk for stent thrombosis. 4
What is DAPT in medicine?
Dual antiplatelet therapy (DAPT) includes the addition of a second antiplatelet agent to aspirin monotherapy. Inherently, this requires a tradeoff between decreasing ischemic risk and stent thrombosis with an increased bleeding risk. Decisions regarding the treatment and duration of DAPT require an individualized assessment of the risk-benefit equation for each patient.
What are the factors to consider when assessing ischemic risk to determine the duration of therapy with DAPT?
PCI and disease complexity are important factors to consider when assessing ischemic risk to determine the duration of therapy with DAPT. 13 A meta-analysis of 10 randomized clinical trials involving 31,666 patients assessing DAPT duration demonstrated that longer DAPT reduced ischemic complications, with a 25% reduction in MI with prolonged DAPT (p = 0.01) and 41% reduction in stent thrombosis (p = 0.06), but a 72% increase in major bleeding (p < 0.0001) and a 22% increase in mortality (p = 0.02) occurred. 14 Consequently, in stable CAD, DAPT is not typically recommended beyond 6 months duration.
How long does DAPT last after PCI?
12 months of DAPT after elective PCI reduced the incidence of death, MI, and stroke compared with DAPT administered for 30 days followed by aspirin alone.