Our library of drug research abstracts drawn from the medical literature is updated on a regular schedule, and you can be assured that new warfarin research articles will be listed here shortly after becoming available to us.
Related Sponsors
Medical research on warfarin
[Oral anticoagulants: warfarin or acenocumarol?]
Med Clin (Barc). 2008 Jun 21; 131(3): 98-100
Roncalés FJ
Med Clin (Barc). 2008 Jun 21; 131(3): 96-7
Oliva Berini E, Galán Alvarez P, Pacheco Onrubia AM
BACKGROUND AND OBJECTIVE: Long half life oral anticoagulants have shown a higher anticoagulation stability and a lower hemorragic risk than those of a short half life. We have compared therapeutic stability and hemorragic risk of acenocoumarol versus warfarin in 2 groups of patients on preventive anticoagulation because of atrial fibrilation (international normalised ratio [INR]: 2-3). PATIENTS AND METHOD: Data on 120 patients treated with acenocoumarol and 120 on warfarin treatment who had started and continued treatment in our hospital for a minimum of a year was collected. RESULTS: The percentage of visits within the intended range of INR (2 to 3) was 65.5% with warfarin and 63.4% with acenocoumarol. Thirty percent of patients on warfarin had 75% or more of their controls within range, while for those treated with acenocoumarol this percentage was 22.5%. In the acenocoumarol group, 0.3 visits/patient/year presented an INR >/= 6 versus 0.07 in the warfarin group (p = 0.003). CONCLUSIONS: Patients treated with acenocoumarol show a higher risk of presenting with an INR >/= 6, but no statistically significant differences are observed in therapeutic stability.
Am J Health Syst Pharm. 2008 Jul 1; 65(13 Suppl 5): S1-5
Talbert RL
PURPOSE: The role of antiplatelet therapy in preventing and treating cardiovascular disease is reviewed. SUMMARY: Cardiovascular disease, especially coronary heart disease, contributes to substantial morbidity and mortality in the United States and raises healthcare costs. Current guidelines from the American College of Cardiology and the American Heart Association, in conjunction with the Society for Cardiovascular Angiography and Interventions, recommend percutaneous coronary intervention (PCI) and stent placement to improve cardiovascular outcomes in patients with acute coronary syndrome, which encompasses unstable angina and myocardial infarction. Following stent placement, dual antiplatelet therapy with aspirin and a thienopyridine (clopidogrel or ticlopidine) significantly reduces the incidence of early major adverse cardiac events and mortality compared with aspirin alone or in combination with warfarin, and is the current standard of care for patients undergoing PCI. Maintenance therapy should be continued for at least one month after placement of a bare-metal stent, and at least three months or six months after placement of a sirolimus- or paclitaxel-eluting stent; ideally, therapy should be continued for one year following PCI. Even utilizing this standard, however, adverse clinical events do occur. In addition, treatment is often discontinued within the first year after stent placement by either the healthcare provider or the patient. CONCLUSION: Premature discontinuation of antiplatelet therapy is associated with an increased risk of adverse outcomes and can be avoided through better understanding of these risks by healthcare professionals and improved patient education.
Clin Appl Thromb Hemost. 2008 Jul; 14(3): 365-8
Küpeli E, Cengiz C, Cila A, Karnak D
Pulmonary thromboembolism is a life-threatening condition resulting mostly from lower extremity deep-vein or pelvic-vein thrombosis. A 46-year-old woman was admitted to hospital with pain on the right side of the chest and hemoptysis. On laboratory analysis, D-dimer level was elevated. Computed tomographic pulmonary angiography revealed intravascular filling defects due to thrombi in right lower lobe pulmonary segmental arteries. Screening for thrombophilic states was normal except for heterozygous mutations of both prothrombin and methylene tetrahydrofolate reductase (MTHFR 677) genes. Homocysteine level was high, and vitamin B12 level and serum ferritin level were reduced. Serum antiparietal antibody was positive, and therefore, pernicious anemia was diagnosed along with iron-deficiency anemia. After the diagnoses were established, enoxaparin followed by warfarin was started in addition to oral vitamin B12, pyridoxine, thiamine, folic acid, and ferroglycine sulfate supplementation. At the end of 8 weeks of the replacement therapy, vitamin B12, folate, and homocysteine levels and red cell volume were found to be normal, with complete resolution of the thrombus confirmed by repeat computed tomographic pulmonary angiography. We conclude that hyperhomocysteinemia due to vitamin B12 deficiency associated with pernicious anemia might have decreased the threshold for thrombosis. In addition, the presence of heterozygous prothrombin and methylene tetrahydrofolate reductase mutations might serve as synergistic cofactors triggering pulmonary thromboembolism.
Rev Med Interne. 2008 Jun 25;
Wahl D, Perret-Guillaume C, Piette JC
The antithrombotic therapy of the antiphospholipid syndrome (APS) has long been based on an empirical strategy. In the absence of appropriate randomised controlled trials, data of retrospective cohort studies were used to establish these strategies. Here we report the results of recent clinical trials, what they add to patient management and the issues that remain unsolved. SECONDARY PROPHYLAXIS OF THROMBOTIC EVENTS: While there is a consensus for prolonged vitamin K antagonist anticoagulation after a first event, two recent randomised clinical trials have compared various intensities of anticoagulation. Both studies have shown that high intensities of warfarin were not superior to conventional intensities. Patients included in these studies had mainly venous thromboembolic events. There has been no study comparing different antithrombotic strategies for arterial thrombosis associated with APS. The WARSS/APASS study, in particular has not been conducted in patients with definite APS and should not be applied to these patients. For now, vitamin K antagonist anticoagulants should remain the treatment of choice in these patients. PRIMARY PROPHYLAXIS OF THROMBOTIC EVENTS: Because of the high incidence of thrombotic events in asymptomatic patients with antiphospholipid antibodies, especially in systemic lupus erythematosus, a clinical trial compared aspirin and placebo in this setting. This study did not demonstrate any benefit of aspirin. We conclude that recent clinical trials indicate the optimal antithrombotic strategy in APS with venous thromboembolism. However, the best options for patients with arterial thrombosis and for primary prophylaxis remain to be established by further studies.
[A 40-year old woman with dizziness and vomiting]
Tidsskr Nor Laegeforen. 2008 Jun 12; 128(12): 1413-5
Holme PA, Michelsen AE
Surgical management of mechanical valve thrombosis: twenty-six years' experience.
J Korean Med Sci. 2008 Jun; 23(3): 378-82
Ahn H, Kim KH, Kim KC, Kim CY
In the present study, the authors investigated the management of mechanical valve thrombosis (MVT). From January 1981 through March 2006, 2,908 mechanical valve replacements were performed in 2,298 patients at our institution. Twenty (0.87%) patients presented with MVT, 14 (70.0%) were women, and the mean age of the patients was 42.0+/-14.0 (27-66) yr. Thrombosis involved mitral in 14 (70.0%), aortic in 2 (10.0%), tricuspid/aortic in 1 (5%), and tricuspid in 3 (15%). The interval from first operation to valve thrombosis was 121.8+/-75.4 (0.9-284.7) months. The most frequent clinical presentation was heart failure (13/20, 65%), and predisposing causes of MVT were: poor compliance with warfarin (7), pregnancy (5), drug interaction (2), and unknown (6). All 20 patients underwent valve replacement: mitral (14, 70.0%), tricuspid (3, 15.0%), aortic (2, 10%) and tricuspid/aortic (1, 5%). One early death occurred due to left ventricular failure, but no late mortality occurred during 63.3+/-49.9 (0.5-165.1) months of follow-up. MVT was treated successfully, and pregnancy and inadequate anticoagulation were found to influence the occurrence of this rare complication.
Warfarin and intracranial haemorrhage.
Blood Rev. 2008 Jun 24;
Appelboam R, Thomas EO
Spontaneous intracerebral haemorrhage is one of the most feared complications of long-term anticoagulation. Warfarin therapy not only increases the likelihood of suffering an intracranial haemorrhage, but also increases the mortality associated with it. This review aims to examine the incidence, pathogenesis, and outcome following a warfarin associated intracranial haemorrhage. It also evaluates the available evidence regarding optimal management of these patients, including timing and strategies for reversal of the coagulopathy, the role of neurocritical care and surgery, and indications for re-anticoagulation once the acute phase has past. The specific management of patients with prosthetic heart valves is also discussed. A summary of current societal guidelines is also included, as are some key practice points.
Continuing warfarin during cutaneous surgery.
Surgeon. 2008 Jun; 6(3): 148-50
Sugden P, Siddiqui H
The risk of haemorrhage from minor cutaneous surgical procedures has long been a concern in the treatment of patients receiving warfarin as anti-coagulation therapy. Interruption, alteration, hospital admission and monitoring have resource implications as well as the potential for complications. Therefore, we wanted to determine whether it was feasible to undertake typical minor plastic surgery procedures without altering patients' warfarin dosage regimens. We undertook a prospective study of 51 patients (age range 36 to 86), with 78 wounds, undergoing a range of minor cutaneous surgical procedures including excision biopsies, local flaps and skin grafts. The patients continued their normal warfarin regimen and the INR was checked on the day of surgery, ranging from 1.1 to 4.0. There were no problems encountered during surgery, but two patients presented with bleeding from a wound a few days post-operatively. We feel that it is unnecessary to modify warfarin regimens for minor cutaneous surgery. However, a well-briefed patient and experienced surgical management with good support facilities are a prerequisite for this.
Images in clinical medicine. Spontaneous thrombolysis of an obstructed mechanical aortic valve.
N Engl J Med. 2008 Jun 26; 358(26): e31
Wake N, Desai AS