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Abstract
The use of low molecular weight heparin (LMWH) for the prevention and treatment of venous thromboembolism has been validated by numerous clinical trials and meta-analyses over the past 25 years. More recently, the possibility of extending treatment with LMWH to the arterial disease where thrombosis is a prominent feature has led to the planning of many clinical trials, several of which have been already published. LMWH has been tested in settings such as acute coronary syndromes, including myocardial infarction, surgery or percutaneous revascularization for coronary and peripheral arteries, and stroke. In most indications, LMWH has proved to be superior to or at least as effective as unfractionated heparin and it is also easier to administer.
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Affiliation(s)
- Giuseppe G Nenci
- Istituto di Medicina Interna e Medicina Vascolare, Università di Perugia, Perugia, Italy
| | - Alessandra Minciotti
- Istituto di Medicina Interna e Medicina Vascolare, Università di Perugia, Perugia, Italy
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2
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Fareed J, Ma Q, Florian M, Maddineni J, Iqbal O, Hoppensteadt DA, Bick R. Unfractionated and Low-Molecular-Weight Heparins, Basic Mechanism of Action and Pharmacology. Semin Cardiothorac Vasc Anesth 2016. [DOI: 10.1177/108925320300700402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Unfractionated heparin has enjoyed sole anticoagulant status for nearly 50 years. Despite a dramatic growth in the development and the introduction of many newer anticoagulant and antithrombotic drugs and polytherapeutic approaches during the past decade, unfractionated and low-molecular-weight heparins remain the drugs of choice for many indications, including surgical anticoagulation, interventional cardiology, and in several additional considerations. Unfractionated heparin has a major role in the areas of vascular medicine and surgery, and it is the only parenteral anticoagulant drug that can be empirically neutralized by such agents as protamine sulfate. The development of low and ultra low-molecularweight heparins, which are a class of depolymerized heparin derivatives with distinct pharmacologic profiles that are largely determined by their composition, represents a refinement for the use of heparin. These drugs produce their major effects by combining with antithrombin Ill and exerting antithrombin and anti-Xa inhibition. The low-molecular-weight heparins also increase non-antithrombin III-dependent effects, such as tissue factor pathway inhibitor release, modulation of adhesion molecules, and the release of profibrinolytic and antithrombotic mediators from the blood vessels. Each of the low-molecular-weight heparins has different cumulative effects, and each product exhibits a distinct profile. Initially developed for the prophylaxis of postsurgical deep vein thrombosis, these drugs are now also used for the treatment of both venous and arterial thrombotic disorders. To a large extent, the low-molecular-weight heparins have replaced unfractionated heparin in most of the subcutaneous indications. This has resulted in a dramatic evolution in anticoagulant management that allows patients with thrombotic disorders to be treated in an outpatient setting. Thus, the introduction of low-molecular-weight heparins represents a major advance in improving the use of heparin. Generic versions of these drugs are likely to be developed as their patents expire. Currently, there are no clear guidelines for the acceptance of the generic versions of branded products. To avoid safety and efficacy-related problems, a generic drug must meet both the chemical and biologic equivalence criterion. Synthetically and biosynthetically derived agents such, as pentasaccharide, will also be introduced for clinical use; however, these drugs will have a narrower therapeutic spectrum due to their monotherapeutic nature. Heparin and its derivatives will continue to have a crucial role in the management of thrombotic and cardiovascular disorders in years to come.
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Affiliation(s)
- Jawed Fareed
- Departments of Pathology and Pharmacology, Hemostasis and Thrombosis Research Laboratories, Loyola University Chicago, 2160 South First Avenue, Maywood, IL 60153
| | | | | | | | | | - Debra A. Hoppensteadt
- Departments of Pathology and Pharmacology, Loyola University Chicago, Maywood, Illinois
| | - Rodger Bick
- Departments of Medicine and Pathology, University of Texas Southwestern Medical Center, Dallas, Texas
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3
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Bolsin S, Hiew C, Birdsey G, Colson M, Gillet J. Coronary artery stents and surgery; the basis of sound perioperative management. Health (London) 2013. [DOI: 10.4236/health.2013.510233] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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4
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Abstract
INTRODUCTION Both arterial and venous thromboembolism constitute a significant disease burden worldwide, leading to major use of healthcare resources. As anticoagulants play a pivotal role in the treatment of these disorders, it is vital for healthcare providers to have sufficient knowledge of their biochemical and clinical attributes. AREAS COVERED Enoxaparin is one of the most commonly used low-molecular-weight heparins in a wide variety of thromboembolic disorders and has several advantages over unfractionated heparin. An analysis of its biophysical profile, with special emphasis on pharmacokinetic and pharmacodynamic properties, is undertaken in this article. In addition, most recent major clinical studies elucidating its role in common thromboembolic conditions are discussed, while keeping the historical perspective at hand. Readers will be able to understand the pharmacologic properties of enoxaparin with their clinical relevance for day-to-day use and critically analyze the amount and weight of scientific evidence behind its use in various disorders. EXPERT OPINION In summary, enoxaparin has been shown, by a vast amount of scientific data, to be a safe and effective agent in the treatment of a whole spectrum of acute coronary syndromes, with similar efficacy and safety in the prevention and treatment of venous thromboembolism.
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Affiliation(s)
- Zafar Iqbal
- Newark Beth Israel Medical Center, Newark, NJ 07112, USA
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5
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McKenzie DB, Rao U, Hobson A, Levy T, Talwar S, Swallow R. A novel strategy for managing clopidogrel-induced adverse skin reactions. EUROINTERVENTION 2009; 5:470-4. [PMID: 19755336 DOI: 10.4244/eijv5i4a75] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
AIMS We conducted a prospective observational study using a course of steroids and antihistamines to treat a cohort of patients who developed skin reactions to clopidogrel, to assess whether dual antiplatelet therapy could be continued in an outpatient setting. METHODS AND RESULTS This study included 2,701 patients who underwent percutaneous coronary intervention (PCI) at our centre over a 23 month period. Patients with skin reactions to clopidogrel were identified and then commenced on five days oral prednisolone (30 mg/od) and chlorpheniramine (4 mg/tds) for seven days. A subsequent telephone survey was performed to evaluate a number of variables. The probability of the adverse reaction being secondary to clopidogrel was assessed using the Naranjo adverse drug reaction probability scale. Twenty (0.7%) patients were identified who developed adverse skin reactions to clopidogrel. There was complete resolution seen in the majority (89%) of patients within an average of 3.2 days following treatment. One patient had partial resolution, and one had no response to treatment, but both were able to continue clopidogrel. CONCLUSIONS We propose a novel, safe and effective way of managing clopidogrel-induced skin reactions using a short course of prednisolone and chlorpheniramine, without stopping or substituting clopidogrel.
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Affiliation(s)
- Daniel B McKenzie
- Dorset Heart Centre, Royal Bournemouth Hospital, Bournemouth, East Dorset, UK.
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6
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Abstract
This article outlines the antiplatelet and antithrombotic therapy used in contemporary percutaneous coronary interventions. It is a comprehensive review of past and present pharmacologic agents and includes a discussion of the more promising potential future therapies. The clinical trials that provide the basis for the current standard of care are provided, as are ongoing trials that will likely shape the future standard. This article is not intended to provide a detailed discussion of precise mechanistic or structural features of each agent but to serve as a practical clinical guide to the interventionalist when choosing specific pharmacotherapies for specific patients in the catheterization laboratory.
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Affiliation(s)
- Nitin Barman
- Interventional Cardiology, Mount Sinai Hospital, One Gustave L. Levy Place, New York, NY 10029, USA
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7
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Karmanoukian H, Attuwabi B, Nader ND. Antithrombotic controversies in off-pump coronary bypass. Semin Thorac Cardiovasc Surg 2005; 17:59-65. [PMID: 16104362 DOI: 10.1053/j.semtcvs.2004.12.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The purpose of this article is to evaluate the use of perioperative antithrombotics in patients undergoing surgical revascularization of the coronary vessels. Although there is a general agreement about the use of anticoagulation during off-pump coronary revascularization (OPCAB), the degree of the required anticoagulation varies from one center to another. The review is divided into four major sections. The first section describes the pathophysiology of the coagulation system in cardiac surgery with and without the use of cardiopulmonary bypass. In this section, we also discuss the interactions between the coagulation system and the inflammatory response to cardiac surgery. The second section examines the role of prophylactic antithrombosis in patients referred to surgical revascularization, and their role in bleeding complications associated with surgery. Heparinization and neutralizing its anticoagulative effects during coronary surgery are discussed in the third section. The fourth section examines the evidence that the inflammatory response contributes to adverse peri-operative events, in particular organ dysfunction, and potential therapeutic strategies to control this response. The review concludes with a summary of potential future research directions and key deficiencies in our knowledge regarding the use of anticoagulants in cardiac surgery.
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Affiliation(s)
- Hratch Karmanoukian
- Department of Surgery and Anesthesiology, State University of New York at Buffalo, Buffalo, NY 14215, USA.
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8
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Orford JL, Berger PB. Modulating thrombotic potential in catheter-based percutaneous coronary and peripheral vascular interventions. J Thromb Thrombolysis 2004; 17:11-20. [PMID: 15277783 DOI: 10.1023/b:thro.0000036024.47732.d6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Thrombosis is an obligatory consequence of all percutaneous vascular interventions. Balloon angioplasty, intravascular stents and other devices routinely used to facilitate dilatation of critical vascular stenoses result in fracture of the intima and exposure of the thrombogenic subendothelium with initiation and perpetuation of platelet activation and aggregation. This not uncommonly results in thrombus formation that may lead to abrupt vessel closure, distal ischemia and tissue infarction, and target organ dysfunction. Fortunately, advances in our understanding of the mechanisms that underlie vascular thrombosis have led to advances in the use of adjunctive pharmacological agents that modulate this pathophysiological response and have led to important reductions in the incidence and severity of thrombotic complications of percutaneous transluminal interventions.
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Affiliation(s)
- James L Orford
- Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN 55905, USA
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9
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Fareed J, Hoppensteadt D, Walenga J, Iqbal O, Ma Q, Jeske W, Sheikh T. Pharmacodynamic and pharmacokinetic properties of enoxaparin : implications for clinical practice. Clin Pharmacokinet 2004; 42:1043-57. [PMID: 12959635 DOI: 10.2165/00003088-200342120-00003] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Enoxaparin is a low-molecular-weight heparin (LMWH) that differs substantially from unfractionated heparin (UFH) in its pharmacodynamic and pharmacokinetic properties. Some of the pharmacodynamic features of enoxaparin that distinguish it from UFH are a higher ratio of anti-Xa to anti-IIa activity, more consistent release of tissue factor pathway inhibitor, weaker interactions with platelets and less inhibition of bone formation. Enoxaparin has a higher and more consistent bioavailability after subcutaneous administration than UFH, a longer plasma half-life and is less strongly bound to plasma proteins. These properties mean that enoxaparin provides a more reliable anticoagulant effect without the need for laboratory monitoring, and also offers the convenience of once-daily administration. Clinical studies have confirmed that these pharmacological advantages translate into improved outcomes. There are important pharmacokinetic and pharmacodynamic differences between enoxaparin, other LMWHs and UFH, and therefore these molecules cannot be regarded as interchangeable.
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Affiliation(s)
- Jawed Fareed
- Department of Pathology, Loyola University Medical Center, Maywood, Illinois, USA.
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10
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Khambekar SK, Kovac J, Gershlick AH. Clopidogrel induced urticarial rash in a patient with left main stem percutaneous coronary intervention: management issues. Heart 2004; 90:e14. [PMID: 14966075 PMCID: PMC1768116 DOI: 10.1136/hrt.2003.027367] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Clopidogrel, an ideal treatment for prevention of subacute stent thrombosis, may not be feasible to use in every patient. Ticlopidine (plus aspirin) is a very good alternative, although the risks of life threatening neutropenia should mandate regular monitoring of blood counts. It is proposed that patients undergoing angioplasty and stenting should carry a warning card in an effort to make the public and general practitioners aware that antiplatelet treatment after angioplasty plays an important part in ensuring successful outcome.
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Affiliation(s)
- S K Khambekar
- Department of Cardiology, Glenfield Hospital, University Hospital of Leicester, Leicester, UK.
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11
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Abstract
Patients receiving chronic anticoagulation therapy pose a clinical challenge when therapy needs to be interrupted for surgical or invasive procedures. Maintaining anticoagulation places them at risk for serious bleeding complications, whereas discontinuing anticoagulation puts them at risk of thromboembolic complications. Most patients can undergo dental procedures, cataract surgery, and diagnostic endoscopy without discontinuing anticoagulation. The main patient groups that may require a periprocedural alternative to oral anticoagulation (periprocedural thromboprophylaxis or bridging) include patients with prosthetic heart valves, atrial fibrillation, and hypercoagulable states and patients with chronic venous thrombosis who are undergoing surgery. Currently, there is little consensus on the appropriate perioperative treatment of patients on long-term warfarin therapy. There are an increasing number of studies that evaluate the benefits of periprocedural bridging with low-molecular-weight heparin (LMWH) in place of unfractionated heparin (UFH). An advantage of LMWH over UFH is that perioperative conversion from warfarin therapy with LMWH can be carried out in the outpatient setting, which is more convenient for patients and is cost effective. As with the use of UFH, there are reports of maternal thromboembolic complications with LMWHs in pregnant women with mechanical heart valves. This review brings together the available data on periprocedural bridging to assess the available options for patients on long-term warfarin therapy who are undergoing surgical procedures. It provides a rationale for using LMWHs while individualizing the risks versus benefits in a given patient population.
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Affiliation(s)
- Syed M Jafri
- Department of Cardiology, Henry Ford Hospital, Detroit, Mich 48202, USA.
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12
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Daoulah A, Segev A, Leblanc K, Chisholm RJ, Strauss BH. Postprocedural low molecular weight heparin in patients at high risk of subacute stent thrombosis. ACTA ACUST UNITED AC 2003; 4:182-5. [PMID: 15321055 DOI: 10.1016/j.carrad.2004.02.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2004] [Accepted: 02/02/2004] [Indexed: 11/16/2022]
Abstract
BACKGROUND Subacute stent thrombosis (SAT) is a dramatic complication of percutaneous coronary stenting occurring in 0.4-20% of cases depending on several angiographic and clinical variables. The role of postprocedural low molecular weight heparin (LMWH) in preventing early events after high-risk PCI is not well established. In this study we describe our experience with postprocedural LMWH in patients deemed to be at high risk of SAT. METHODS Thirty-six patients who were treated with subcutaneous LMWH for at least 7 days after the intervention were identified from our database. All cineangiograms and charts were retrospectively reviewed to confirm the high-risk intervention properties. Thirty-day and long-term major adverse coronary events (MACEs) were documented in all patients. RESULTS The most common indications for LMWH were the deployment of > or =3 consecutive stents, the presence of intracoronary thrombus or ulceration, poststenting residual stenosis, contraindication to aspirin or thienopyrideines, and persistent dissection. The majority of patients (61%) had > or =2 risk factors. Mean postprocedural treatment period was 12+/-3 days. At 30 days, none of the patients experienced a MACE including death, myocardial infarction, and repeat revascularization. No major bleeding occurred and one patient (2.7%) had a minor bleeding. At a mean follow-up of 31 months, MACE occurred in 17% of patients. CONCLUSIONS Postprocedural LMWH is safe and effective in preventing SAT in patients undergoing high-risk coronary intervention.
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Affiliation(s)
- Amin Daoulah
- Roy and Ann Foss Interventional Cardiology Research Program, Terrence Donnelly Heart Center, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
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13
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Affiliation(s)
- Richard M Green
- Division of Vascular Surgery, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
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14
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Shatin D, Schech SD, Brinker A. Ambulatory use of ticlopidine and clopidogrel in association with percutaneous coronary revascularization procedures in a national managed care organization. J Interv Cardiol 2002; 15:181-6. [PMID: 12141141 DOI: 10.1111/j.1540-8183.2002.tb01053.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The aim of this study was to quantify ambulatory use of ticlopidine and clopidogrel in association with percutaneous coronary revascularization procedures (PTCA, atherectomy, stent) in a national managed care organization. Retrospective administrative claims data over a 3-year period (1996-1998) from 12 UnitedHealth Group-affiliated health plans in four geographic regions were collected. Pharmacy and medical claims data were used to determine the patients exposed to ticlopidine and clopidogrel between January 1, 1996 and December 31, 1998, the duration of use, prescriptions within 2 weeks of a coronary procedure, and stent patients prescribed either drug within 2 weeks of stent placement in 1998. Substantial short-term use of ticlopidine and clopidogrel was found. The percentage of members with duration of use < or = 30 days ranged from 50.4% in 1996 to 56.9% in 1998 for ticlopidine and was 52.7% for clopidogrel. In 1998, 46% and 33% of ticlopidine and clopidogrel users, respectively, had a medical claim for a coronary procedure that fell within 2 weeks of a prescription. The rate was lower for Medicare beneficiaries. In 1998, 78% of stent patients filled a prescription for either drug within 2 weeks of stent implantation. Although little difference was found overall in the use of these agents across geographic regions, a higher proportion of stent patients in the Southeast were prescribed ticlopidine within this time frame. The findings suggest that during the study time period ticlopidine and clopidogrel are frequently used off-label in association with percutaneous coronary revascularization procedures. These results were important in considering the overall benefit-risk profile.
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Affiliation(s)
- Deborah Shatin
- Center for Health Care Policy and Evaluation, MN008-W109, UnitedHealth Group, 9900 Bren Rd. East, Minnetonka, MN 55343, USA
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15
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Berger PB, Mahaffey KW, Meier SJ, Buller CE, Batchelor W, Fry ETA, Zidar JP. Safety and efficacy of only 2 weeks of ticlopidine therapy in patients at increased risk of coronary stent thrombosis: results from the Antiplatelet Therapy alone versus Lovenox plus Antiplatelet therapy in patients at increased risk of Stent Thrombosis (ATLAST) trial. Am Heart J 2002; 143:841-6. [PMID: 12040346 DOI: 10.1067/mhj.2002.121929] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Controversy exists regarding the frequency of late stent thrombosis among patients treated with intracoronary stents and the most appropriate duration of treatment with a thienopyridine that is required to prevent this complication. METHODS We analyzed the frequency of stent thrombosis and other ischemic events in the Antiplatelet Therapy alone versus Lovenox plus Antiplatelet therapy in patients at increased risk of Stent Thrombosis (ATLAST) trial. In the ATLAST trial, 1102 patients at increased risk of stent thrombosis (ST-elevation myocardial infarction within 48 hours, diffuse distal disease, a large amount of thrombus, acute closure, residual dissection, etc) were randomly assigned to receive either enoxaparin (40 or 60 mg given every 12 hours for 14 days) or placebo; all patients received aspirin (325 mg daily) and ticlopidine (250 mg twice daily) for only 14 days. RESULTS The primary end point, the 30-day combined incidence of death, nonfatal myocardial infarction, and urgent revascularization, was reached in 2.3% of patients (1.8% of patients taking enoxaparin vs 2.7% of patients taking placebo; P =.295). However, during the 15th through 30th days, the frequency of ischemic events was only 0.73%, and only 0.27% (3/1102) of patients had possible stent thrombosis (95% CI 0.06, 0.77). CONCLUSION The frequency of stent thrombosis and other adverse ischemic events in the 15th through 30th days after stent placement in even high-risk stent patients treated with ticlopidine for only 2 weeks is low whether or not enoxaparin is administered.
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Batchelor WB, Mahaffey KW, Berger PB, Deutsch E, Meier S, Hasselblad V, Fry ET, Teirstein PS, Ross AM, Binanay CA, Zidar JP. A randomized, placebo-controlled trial of enoxaparin after high-risk coronary stenting: the ATLAST trial. J Am Coll Cardiol 2001; 38:1608-13. [PMID: 11704394 DOI: 10.1016/s0735-1097(01)01612-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES We performed a multicenter, double-blind placebo-controlled trial to examine the efficacy and safety of enoxaparin in patients at high risk for stent thrombosis (ST). BACKGROUND The optimal antithrombotic regimen for such patients is unknown. METHODS We randomized 1,102 patients with clinical, angiographic or ultrasonographic features associated with an increased risk of ST to receive either twice-daily injections of weight-adjusted enoxaparin or placebo for 14 days after stenting. All patients received aspirin and ticlopidine. The primary end point was a 30-day composite end point of death, myocardial infarction (MI) or urgent revascularization. RESULTS The target enrollment for the study was 2,000 patients. However, the trial was terminated prematurely at 1,102 patients after interim analysis revealed an unexpectedly low event rate. The primary outcome occurred in 1.8% enoxaparin-treated patients versus 2.7% treated with placebo (odds ratio [OR] 0.66; 95% confidence interval [CI] 0.29 to 1.5, p = 0.30); for death or MI the rates were 0.9% vs. 2.2%, respectively (OR 0.41, 95% CI 0.14 to 1.2, p =0.13); and for MI, 0.4% vs. 1.6%, respectively (OR 0.22, 95% CI 0.05 to 0.99, p = 0.04). The groups had comparable rates of major bleeding (3.3% for enoxaparin, 1.6% for placebo, p =0.08), but minor nuisance bleeding was increased with enoxaparin (25% vs. 5.1%, p < 0.001). CONCLUSIONS The clinical outcomes of patients at increased risk of ST are more favorable than previously reported, rendering routine oral antiplatelet therapy adequate for most. However, given its relative safety and potential to reduce the risk of subsequent infarction, a 14-day course of enoxaparin may be considered for carefully selected patients.
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Affiliation(s)
- W B Batchelor
- The Duke Clinical Research Institute, Durham, North Carolina, USA
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Affiliation(s)
- G Hausdorf
- Department of Pediatric Cardiology and Pediatric Intensive Care Medicine, Hannover Medical School, Carl-Neuberg Str. 1, D-30625 Hannover, Germany.
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18
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Cohen M. The role of low-molecular-weight heparins in the management of unstable angina and non-ST-segment elevation myocardial infarction. J Thromb Thrombolysis 2001; 11:171-4. [PMID: 11406733 DOI: 10.1023/a:1011284902244] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- M Cohen
- Catheterization Lab, Hahnemann University Hospital, Philadelphia, PA 19102-1192, USA.
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Abstract
In recent years, academic research institutions have increasingly sought to commercialize their discoveries, providing the opportunity to raise venture capital and benefit financially from their developments. In the last 6 years, Hamilton Civic Hospitals Research Center, affiliated with McMaster University, Ontario, Canada, has set up two companies, Vascular Therapeutics and Osteokine, to commercialize its discoveries in thrombosis and osteoporosis. Epidemiological evidence shows a continuing socioeconomic burden of both of these disorders, thereby offering opportunities for new drug development. Key areas in the field of thrombosis include novel parenteral anticoagulants to replace heparin as adjunctive therapy in acute coronary syndromes, safer and more practical oral anticoagulants that do not require monitoring to replace coumarins, and oral antiplatelet drugs for use in combination with aspirin. Since their creation, Vascular Therapeutics and Osteokine have attracted major funding and developed several patentable compounds that show clinical and commercial promise.
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Affiliation(s)
- J Hirsh
- Hamilton Civic Hospital Research Center and McMaster University, Hamilton, Ontario, Canada
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20
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Timms ID. Low-Molecular-Weight Heparins: Overview and Potential Uses in Interventional Radiology. J Vasc Interv Radiol 2001. [DOI: 10.1016/s1051-0443(01)70027-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Cosmi B, Rubboli A, Castelvetri C, Milandri M. Ticlopidine versus oral anticoagulation for coronary stenting. Cochrane Database Syst Rev 2001; 2001:CD002133. [PMID: 11687144 PMCID: PMC8406639 DOI: 10.1002/14651858.cd002133] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND A 2-4 week course of ticlopidine plus aspirin following coronary stenting is considered effective in preventing thrombotic occlusion of the stented vessel and safe in regards to bleeding and peripheral vascular complications. However, rare, although potentially life-threatening haematological complications have been reported with this drug regimen. OBJECTIVES To evaluate the efficacy and safety of ticlopidine plus aspirin versus oral anticoagulants after coronary stenting SEARCH STRATEGY Electronic search of the Cochrane Library, Medline, Embase from 1991 to June 1999; references from trials and experts. SELECTION CRITERIA Randomised controlled trials comparing ticlopidine plus aspirin versus oral anticoagulants (either with or without aspirin) after elective or bail out coronary stenting. DATA COLLECTION AND ANALYSIS Three reviewers assessed trial quality and compiled data on outcomes including: total mortality, non fatal myocardial infarction and revascularization occurring within the first 30 days after hospitalization, stent thrombosis on angiography, major and minor bleeding, neutropenia, thrombocytopenia, thrombotic thrombocytopenic purpura. MAIN RESULTS Four trials (n=2436 patients) were included. Ticlopidine plus aspirin compared to oral anticoagulants significantly reduced the risk of non-fatal acute myocardial infarction and revascularization at 30 days, combined negative events (mortality, myocardial infarction, revascularization at 30 days) (RR: 0.41; 95% CI: 0.25-0.69; NNT for 30 days: 22; 95% CI: 14-45), and major bleeding (RR in high quality studies: 0.24; 95% CI: 0.07-0.79). Ticlopidine plus aspirin compared to oral anticoagulants significantly increased the risk of eutropenia, thrombocytopenia and neutropenia (RR 5; 95% CI: 1.08-13.07; NNT for 30 days: 142; 95% CI: 76-1000). Ticlopidine plus aspirin vs oral anticoagulation did not affect all cause mortality. Ticlopidine plus aspirin significantly reduced the risk of stent thrombosis (angiography) which was seen only on studies with blinded outcome assessment (RR: 0.14; 95% CI: 0.03-0.60; NNT for 30 days: 33; 95% CI:16-166). Minor bleeding was reported only in one study and no studies recorded thrombotic thrombocytopenic purpura (TTP). REVIEWER'S CONCLUSIONS Ticlopidine plus aspirin after coronary stenting is effective in reducing the risk of the revascularization, non fatal myocardial infarction and bleeding complications when compared with oral anticoagulants. No effect is observed on total mortality. However, the haematological side effects of ticlopidine are still a matter of concern, and strict monitoring of blood-cell counts is recommended. Physicians should also be aware of the possibility of rare although potentially life-threatening complications such as TTP
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Affiliation(s)
- B Cosmi
- Division of Angiology Department of Cardiovascular Diseases, University of Bologna, University Hospital S.Orsola-Malpighi, via Massarenti 9, Bologna, Italy, 40138.
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Cohen M. The role of low-molecular-weight heparins in arterial diseases: optimizing antithrombotic therapy. Thromb Res 2000; 100:V131-9. [PMID: 11053626 DOI: 10.1016/s0049-3848(00)00273-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
On the basis of current evidence, all patients with acute coronary syndromes should receive optimized medical therapy, whether or not they ultimately undergo an invasive revascularization procedure, to improve both clinical outcomes and cost effectiveness. While standard aspirin and unfractionated heparin (UFH) have improved short-term outcomes, they do not eliminate the risk of recurrent ischemic episodes. The recent introduction of platelet fibrinogen receptor antagonists and low-molecular-weight heparins (LMWHs) has offered an opportunity to develop more aggressive antithrombotic regimens. The LMWHs have been thoroughly evaluated in unstable angina and non-Q wave myocardial infarction (UA/NQMI), and have demonstrated improved efficacy compared to standard UFH, without an increase in major complications caused by bleeding. Experience has also been gathered using LMWHs in other arterial diseases (such as pregnant patients with prosthetic heart valves) and as an adjunctive therapy with thrombolytics for acute myocardial infarction. Lastly, studies are currently underway evaluating LMWHs in patients with atrial fibrillation.
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Affiliation(s)
- M Cohen
- Division of Cardiology, Hahnemann University Hospital, Philadelphia, PA 19102-1192, USA
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Goodman SG. Low-molecular-weight heparin in patients with non-ST-segment elevation acute coronary syndrome: role in the emergency department. J Emerg Med 2000; 19:3S-11S. [PMID: 11050378 DOI: 10.1016/s0736-4679(00)00248-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Intravenous unfractionated heparin (UFH) has been shown to be an effective therapy in reducing the risk of death or myocardial infarction in patients with unstable angina. Low molecular weight heparins demonstrate improved pharmacologic and pharmacokinetic properties relative to standard heparin, and these advantages have been translated into similar or even greater clinical efficacy in several large-scale clinical trials evaluating their use. The simple mode of administration and lack of dependency on anticoagulation monitoring make low-molecular-weight heparins an extremely attractive option in the treatment of patients with acute ischemic coronary syndromes presenting without persistent ST-segment elevation.
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Affiliation(s)
- S G Goodman
- University of Toronto and Division of Cardiology, Canadian Heart Research Centre, St. Michael's Hospital, Toronto, Ontario, Canada
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Panning CA. Antithrombotic Therapy during and after Intracoronary Stenting. J Pharm Technol 2000. [DOI: 10.1177/875512250001600502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Objective: To evaluate the impact on patient outcomes of antithrombotic therapy during and after intracoronary stenting. Data Sources: A MEDLINE search (1966-July 2000) for English-language clinical trials and review articles using the search terms stent and coronary with one or more of the following search terms: abciximab, tirofiban, orofiban, xemilofiban, eptifibatide, aspirin, heparin, enoxaparin, tinzaparin, dalteparin, hirudin, danaparoid, dipyridamole, cilostazol, dextran, warfarin, anticoagulant, ticlopidine, and Clopidogrel. References from these articles were reviewed for additional articles. Pharmaceutical companies were contacted to identify unpublished studies. A total of 177 sources were initially identified. Study Selection: Studies were selected through an unblinded individual review for prospective, randomized clinical trials evaluating patient outcomes related to antithrombotic therapy during or after intracoronary stent placement. Additional human and animal studies were included for background and introductory information. Data Extraction: Patient characteristics in each study were compared with those of the overall stent population. The primary end point measurements were defined. The completeness of follow-up and power analysis was assessed. Data Synthesis: Intracoronary stenting is now a common modality for maintaining patency of occluded arteries. Antithrombotic therapy during coronary artery stent placement is changing as knowledge about the pathophysiology of thrombus formation expands and new medications become available. Development of new stent placement techniques, new stent designs, and methods of restenosis irradiation or prevention have coincided with evolving antithrombotic regimens. Conclusions: The current antithrombotic regimen used in coronary artery stenting is complex, but has a lower incidence of hemorrhagic complications and thrombosis compared with previous anticoagulant regimens. Antithrombotic therapy may need to be tailored to individual patient contraindications.
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Abstract
This review assesses the trial data for low-molecular-weight heparin (LMWH) use in cardiology. LMWHs have been shown to be more convenient to use compared with unfractionated heparin. The use of LMWHs in prevention and treatment of deep vein thrombosis is now established. Use of LMWHs in cardiology is gathering momentum. The most compelling published data are in unstable angina and non-Q-wave myocardial infarction (MI). LMWHs are at least as effective as unfractionated heparin in terms of the composite endpoint of death and MI. Conclusive benefits of LMWH use to prevent restenosis after stent insertion or percutaneous transluminal coronary angioplasty have not been established. The data in MI and atrial fibrillation are still preliminary, but encouraging.
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Affiliation(s)
- R I Shulman
- Department of Pharmacy, University College London Hospitals, Mortimer Street, W1N 8AA, London, UK.
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Kaul S, Shah PK. Low molecular weight heparin in acute coronary syndrome: evidence for superior or equivalent efficacy compared with unfractionated heparin? J Am Coll Cardiol 2000; 35:1699-712. [PMID: 10841215 DOI: 10.1016/s0735-1097(00)00648-3] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
This article will review the results of recent clinical trials evaluating low molecular weight heparins (LMWHs) in the management of patients with acute coronary syndromes of unstable angina and non-ST segment elevation MI. Low molecular weight heparins are a new class of anticoagulants that have a number of advantages over unfractionated heparin (UFH) leading to their increasing use for thrombotic vascular disorders. There is convincing evidence that LMWH is more effective than placebo and at least as effective as UFH in reducing the hard end points of death and recurrent myocardial infarction. Convincing evidence for a superior efficacy is mostly limited to the least robust but most prevalent end point of recurrent angina, and benefits appear to be confined predominantly to high-risk patients. The benefits are sustained long-term, but there appears to be no incremental benefit with prolonged treatment. The risk for major bleeding is approximately equivalent to UFH, but minor hemorrhage is clearly increased, especially with vascular instrumentation. The increased bleeding risk together with its long half-life and absence of specific antidote warrants exercising caution when using LMWH with coronary intervention. Low molecular weight heparins have the potential of being cost-neutral or even cost-saving by reducing resource utilization, especially in the setting of aggressive interventional practice pattern. Last, the issue of whether one LMWH preparation is more effective and cost-effective than others remains an open question that can be answered only by direct head-to-head comparison of different LMWH preparations in randomized trials. In conclusion, subcutaneous weight-adjusted LMWH is as effective and safe as intravenous UFH in the management of patients with acute coronary syndromes. The logistic ease of administration without the need for monitoring anticoagulation appears to be the major advantage over UFH.
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Affiliation(s)
- S Kaul
- Department of Medicine, Cedars-Sinai Medical Center, and UCLA School of Medicine, Los Angeles, California 90048, USA.
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27
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Jafary FH, Kimmelstiel CD. Antiplatelet therapy in interventional cardiology: II. Glycoprotein IIb/IIIa inhibitors. J Thromb Thrombolysis 2000; 9:163-74. [PMID: 10613998 DOI: 10.1023/a:1018775015882] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- F H Jafary
- Cardiac Catheterization Laboratory, Division of Cardiology, New England Medical Center, Boston, Massachusetts 02111, USA
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MUHLESTEIN JOSEPHB, MAYCOCK CHLOEALLEN. Routine Stenting or Provisional Stenting: Which Is Better? A Look At Presently Existing Data. J Interv Cardiol 1999. [DOI: 10.1111/j.1540-8183.1999.tb00263.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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31
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Affiliation(s)
- G Montalescot
- Cardiology Department, Pitié-Salpêtrière University Hospital, Paris, France.
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Ruef J, Lighezan R, Schuler G, Nordt T, Kübler W, Bode C. Ticlopidine versus phenprocoumon in patients with Palmaz-Schatz coronary stent: occlusion rates and markers of hemostatic activation. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s0268-9499(99)90099-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Affiliation(s)
- D Aguilar
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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