Mesenteric vein thrombosis
Peter Gloviczki, Michael C. Dalsing, Bo Eklöf, Fedor Lurie, Thomas W. Wakefield, Monika L. Gloviczki in Handbook of Venous and Lymphatic Disorders, 2017
Blood tests may be very helpful but are not very specific in the evaluation of patients with suspected MVT. The complete blood count with differentials is important for assessing both the hemoglobin and hematocrit in order to ensure that occult bleeding is not overlooked. Polycythemia rubra vera, essential thrombocythemia, leukemia, and other hematologic disorders which may predispose to venous thrombosis can also be screened for with this test. The white blood count will alert the physician to infections related to bowel infarction or perforation. Elevated serum lactate levels and metabolic acidosis will help to identify those patients with a severely ischemic or infarcted bowel.41 If levels are higher than 1000 U/L, acute pancreatitis should be considered. Transaminase elevation implies additional involvement of the portal or hepatic venous system. This is particularly relevant to the initiation of treatment with vitamin K antagonists. Fibrin D-dimer elevation may also be helpful in determining the timing of thrombosis. An acute thrombus is anticipated to be accompanied by significant D-dimer elevations. In the subacute or chronic setting, thrombosis evolution may no longer be associated with D-dimer abnormalities.
Briefing Therapeutic Approaches in Anticoagulant, Thrombolytic, and Antiplatelet Therapy
Debarshi Kar Mahapatra, Sanjay Kumar Bharti in Medicinal Chemistry with Pharmaceutical Product Development, 2019
Vitamin K antagonists inhibit the enzyme vitamin K epoxide reductase, which uses vitamin K to modify several coagulation zymogens (factor VII, factor IX, factor X and prothrombin). Therefore, antithrombotic effect is a consequence of their inhibition of the vitamin K-dependent post-translational γ-carboxylation of glutamic acid (Gla) residues in the previously mentioned procoagulant zymogens. γ-carboxyglutamic acid residues (a specific domain) are an essential requirement for these proteins for permitting the binding of procoagulants to phospholipid surfaces and hence proper assembly into the active tenase and prothrombinase complexes. Deficiency of Gla domains turns FVIIa, FIXa, FXa, and thrombin into physiologically very poor procoagulants. These antagonists are used for long-term anticoagulant therapy. These inhibitors were introduced more than 50 years ago and still in clinical use today. Vitamin K antagonists are Warfarin and its analogs, such as phenprocoumon, acenocoumarol, and dicumarol (Figure 7.5).
Perioperative cardiovascular evaluation and treatment of elderly patients undergoing noncardiac surgery
Wilbert S. Aronow, Jerome L. Fleg, Michael W. Rich in Tresch and Aronow’s Cardiovascular Disease in the Elderly, 2019
Management of anticoagulation for stroke prophylaxis in these patients is addressed on a case-by-case basis based on the ischemic event benefit and individual bleeding risk. Vitamin K antagonists (warfarin) have been the most common anticoagulants used for stroke prophylaxis in patients with AF or mechanical heart valves, and for treatment of thromboembolism. However, there is increasing use of novel oral anticoagulants including rivaroxaban, edoxaban, apixaban, and dabigatran for stroke prophylaxis in AF and for treatment of thromboembolism. Warfarin is easily reversed with administration of clotting factors. Even though there is ongoing research on several reversal agents, novel oral anticoagulants are not readily reversible due to unavailability of these reversal agents except for dabigatran (1).
Residual risk reduction opportunities in patients with chronic coronary syndrome. Role of dual pathway inhibition
Published in Expert Review of Clinical Pharmacology, 2020
José R. González-Juanatey, Manuel Almendro-Delia, Juan Cosín-Sales, Sergi Bellmunt-Montoya, Juan José Gómez-Doblas, Vincent Riambau, Xavier García-Moll, Javier García-Alegría, José Luis Hernández, Francisco S. Lozano, Carmen Suarez Fernández
The subsequent question is whether all anticoagulants have a positive effect on preventing ischemic events among patients with CCS, or only some of them. Vitamin K antagonists act on the anticoagulation cascade through the inhibition of the vitamin K-dependent clotting factors. Different studies have shown that after myocardial infarction, warfarin, in combination with aspirin or given alone, is superior to aspirin alone in reducing the incidence of MACE but with a marked higher risk of serious bleeding and without reducing mortality [30–32]. In the RE-DEEM study, dabigatran, an oral direct thrombin inhibitor, reduced coagulation activity in patients with a recent myocardial infarction but was associated with a dose-dependent increase in bleeding events [33]. In the RE-LY trial, compared with warfarin, there was a trend towards a higher risk of myocardial infarction among patients with nonvalvular atrial fibrillation treated with dabigatran [34,35]. These results could be partially explained by the fact that dabigatran attenuates thrombin generation to a lesser extent than warfarin and also because dabigatran increases platelet reactivity by enhancing the thrombin receptor density on platelets [36,37].
Atrial fibrillation, diabetes and anticoagulation with direct oral anticoagulants: time to reconsider duration of the disease to evaluate the bleeding risk?
Published in Acta Cardiologica, 2021
Olivier Gach, Luc A. Pierard
Atrial fibrillation (AF) is the most common chronic aging related arrythmia worldwilde [1] and is known for a long time to be associated with a significant increase of stroke (4- to 5-fold) [2]. To prevent these events, lifelong oral anticoagulation is indicated in the majority of the patient presenting AF. Initially, patients were treated by a vitamin K antagonist such as warfarin. Although these treatments reduce the risk of stroke, compared to control therapy, they increase the risk of bleeding [3]. Moreover, vitamin K antagonists are difficult to use in daily clinical practice because of several interactions with food and drugs, because they require regular biological monitoring leading to an inaccurate anticoagulation in numerous patients [4]. Since 2010, four non-vitamin K antagonist direct oral anticoagulants (DOACs) have been successively approved and are nowadays recommended instead of warfarin for the majority of patients with AF [5].
Usefulness of a left ventricular assist device in patients with left ventricular noncompaction
Published in Baylor University Medical Center Proceedings, 2018
Helen Hashemi, Fayez S. Raza, David M. Harmon, Tony Alias, Joost Felius, Melody J. Sherwood
Treatment of LVNC is based on clinical presentation.1,3 Oral vitamin K antagonists are recommended for anticoagulation for patients with atrial fibrillation, cardioembolic events, severe systolic dysfunction, or atrial/ventricular thrombus.1 Heart failure in patients with LVNC is treated with guideline-directed medical therapy. If heart failure does not respond to medical therapy, heart transplantation or LVAD should be considered.1,11,14 Prior case series have shown increased risk of pump thrombosis and thromboembolic events in patients with LVNC after LVAD, leading to uncertainty about the risk-benefit balance of LVAD therapy in this population.1,11,15 Cardiopulmonary bypass is recommended during LVAD implantation to allow for intraventricular cavitary inspection and removal of clots or trabeculae.11,15 In both of our patients, LVAD implantation was performed successfully with no modification of posthospitalization anticoagulation goals or strategies or extensive intraoperative debridement.16 To date, no thromboembolic events have occurred in either patient, offering support for LVAD therapy for patients with LVNC with intractable heart failure when the transplant is not immediately available or is contraindicated.
Related Knowledge Centers
- Anticoagulant
- Coagulation
- Receptor Antagonist
- Rodenticide
- Teratology
- Vitamin K
- Thrombosis
- Competitive Inhibition
- Superwarfarin
- 4-Hydroxycoumarins