Anticoagulants myocardial infarction

Acute myocardial infarction. Anticoagulation with heparin is used to reduce the risk of venous thromboembolism, and the risk and size of emboli from mural thrombi following acute myocardial infarction. 

Warfarin has been the primary oral anticoagulant used in the United States for the past 60 years. Warfarin is the anticoagulant of choice when long-term or extended anticoagulation is required. Warfarin is FDA-approved for the prevention and treatment of VTE, as well as the prevention of thromboembolic complications in patients with myocardial infarction, atrial fibrillation, and heart valve replacement. While very effective, warfarin has a narrow therapeutic index, requiring frequent dose adjustments and careful patient monitoring.15,29... 

Arterial thrombi (white thrombi) are formed initially from both platelets and fibrin in medium-sized arteries on the basis of atherosclerosis. These thrombi can lead to symptoms of, among others, myocardial ischemia and myocardial infarction. The treatment is primarily aimed at prevention of thrombus formation with platelet aggregation inhibitors. For the treatment of myocardial infarction thrombolytic agents are used and for secondary prevention both oral anticoagulants and anti-platelet drugs are employed. 

Small subcutaneous closes of heparin have been found to be effective in high-nsk post-surgical patients and in patients with acute myocardial infarction. The preventive treatment is commenced a few hours before an operative procedure and continued postoperatively for 4 to 5 days. As the result of a study in 1975. low-dose heparin prophylaxis in high-nsk patients who undergo abdomina-thoracic surgery has become a widely accepted practice, However, preventive anticoagulant therapy, to date, has been unsatisfactory and controversial in the instances of hip surgery or prostatectomy. 

Stella Jp Stella RE, laffaldano RA, et al, Anticoagulation with bivalirudin during percutaneous coronary intervention for ST-segment elevation myocardial infarction, J Invasive Cardiol 2004 16 451-454. 

In the meta-analysis with I I randomized studies, anticoagulant effects in ACS and PCI were compared between a direct antithrombin agent and UFH, The direct thrombin inhibitor showed better outcome in death or myocardial infarction than UFH (19). DTIs are expected to be an alternative to UFH for PCI. 

Zeymer U, von Essen R, Tebbe U, et al, Frequency of optimal anticoagulation for acute myocardial infarction after thrombolysis with front-loaded recombinant tissue-type plasminogen activator and conjunctive therapy with recombinant hirudin (HBW 023). ALKK Study Group. Am J Cardiol 1995 76 997-1001. 

The Hirulog and Early Reperfusion or Occlusion (HERO) -2 Trial Investigators. Thrombin-specific anticoagulation with bivalirudin versus heparin in patients receiving fibrinolytic therapy for acute myocardial infarction the HERO-2 randomised trial. Lancet 2001 3 58 1 855-1 863,... 

To understand the evolution of therapy of the acute coronary syndrome (ACS), which includes unstable angina, acute myocardial infarction, and interventional therapy— percutaneous coronary intervention (PCI), it is most useful to trace the historical events that provided a rationale for the use of anticoagulant and antiplatelet drugs, The focus of this chapter is upon the explosion in knowledge of the physiology of the hemostatic mechanism and will trace the rational development of therapy based upon the pathophysiology of the ACS over the past 40 years. 

Today, standard therapy for myocardial infarction or luminal narrowing includes thrombolytics, anticoagulants, and often interventional procedures such as PTCA. With its introduction... 

The scope of the medical problems which require the use of anticoagulant drugs cannot be overstated. Arterial thrombosis is a major contributor to the number one (acute myocardial infarction), number three (stroke) and number four (renal) causes of death in the United States (1J. Venous thromboembolism is the most common non-surgical cause of death in patients hospitalized for major orthopedic procedures, the most frequent non-obstetrical cause of postpartum death, and a major cause of death in patients with chronic cardiac and pulmonary disease (1 ). Venous thrombosis is estimated to lead to the hospitalization of approximately... 

The coumarin anticoagulants, which include warfarin [WAR far in] and dicumarol [dye KOO ma role] (formerly bishydroxycoumarin) owe their action to their ability to antagonize the cofactor functions of vitamin K. Initially used as a rodenticide, warfarin is now widely employed clinically as an oral anticoagulant. Conflicting opinions exist concerning the usefulness of these agents in clinical situations such as myocardial infarction and hip arthroplasty. The potential... 

Pharmacokinetics Streptokinase therapy is instituted within 4 hours of a myocardial infarction and is infused for 1 hour. Its ti/2 is less than a half-hour. Thromboplastin time is monitored and maintained at two to five times control value. On discontinuation of treatment, either heparin or oral anticoagulants may be administered. 

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