Venous thrombotic events

Axitinib (Inlyta) VEGFR-1, 2, and 3 2012 CV, CNS, pulmonary, GI 1 gastric emptying TBP, iHR ECG in dog—no effect 6-mraith mouse, 9-month dog Broken teeth (mice), spleen Hypertension, arterial and venous thrombotic events, hemorrhagic events, gastrointestinal perforatirai, hypothyroidism, RPLS, proteinuria, liver enzyme elevation... 

Venous thrombotic events (VTE) are more common in WG, both in children (32,99) and adults (99,100), and may reflect venulitis. In addition, circulating cardiolipin antibody was noted in up to 19% of adults with WG (99,101), although this likely does not explain the increased incidence of VTE in WG (102). 

Merkel PA, Lo GH, Holbrook IT, et al. Brief communication high incidence of venous thrombotic events among patients with Wegener granulomatosis the Wegener s Clinical Occurrence of Thrombosis (WeCLOT) Study. Ann Intern Med 2005 142(8) 620-626. 

Laboratory tests for hypercoagulable states should be done only when the cause of the stroke cannot be determined based on the presence of well-known risk factors. Protein C, protein S, and antithrombin III are best measured in steady state rather than in the acute stage. Antiphospholipid antibodies are of higher yield but should be reserved for patients aged less than 50 years and those who have had multiple venous or arterial thrombotic events or livedo reticularis. 

Morbidity and mortality in HIT are related to thrombotic events. Venous thrombosis occurs most commonly, but occlusion of peripheral or central arteries is not infrequent. If an indwelling catheter is present, the risk of thrombosis is increased in that extremity. Skin necrosis has been described, particularly in individuals treated with warfarin in the absence of a direct thrombin inhibitor, presumably due to acute depletion of the vitamin -dependent anticoagulant protein C occurring in the presence of high levels of procoagulant proteins and an active hypercoagulable state. 

Thrombotic (blood clot) events, and subsequent complications, are a leading cause of morbidity and mortality in the general population.1 In 2005, it was estimated that there were more than 900,000 total venous thromboembolism events in the United States,2 two thirds of which were acquired in hospital. More than 600,000 of those were nonfatal venous thromboembolism events. Nearly 300,000 were fatal events, including more than 2,200 cases of deep venous thrombosis and 294,000 cases of pulmonary embolism. The majority deaths (93%) were due to sudden fatal pulmonary embolism, or were a consequence of undiagnosed venous thromboembolism. It was estimated that 340,000 patients developed complications from venous thromboembolism, including 336,000 with postthrombotic syndrome and 3,300 with chronic thromboembolic pulmonary hypertension. 

Thrombin is known to play a cracial role in the overall thrombotic events leading to both arterial and venous thrombosis (36). Beside the transformation of fibrinogen to fibrin, this enzyme is claimed to mediate the activation of platelets and macrophages and produces... 

Henrickson KJ, Axtell RA, Hoover SM, Kuhn SM, Pritchett J, Kehl SC, Klein JP. Prevention of central venous catheter-related infections and thrombotic events in immunocompromised children by the use of vancomy-cin/ciprofloxacin/heparin flush solution A randomized, multicenter, double-bhnd trial. J Qin Oncol 2000 18(6) 1269-78. 

In a placebo-controlled study of severely anemic patients with low-grade non-Hodgkin s lymphoma, chronic lymphocytic leukemia, or multiple myeloma, a fatal case of pulmonary embolism was thought to have been related to treatment with epoetin beta (95). Thrombotic events, such as vascular access thrombosis, venous thrombosis, and pulmonary embolism, have occurred after treatment with epoetin or darbepoetin alfa (96). It is therefore recommended that a rapid rise in the hemoglobin concentration be avoided and that care should be taken that the hemoglobin concentration does not exceed 12.1 g/dl (7.5 mmol/1) (97). 

Excessive factor VIII activity in vulnerable arterial beds, for example atherosclerotic vessels, could lead to thrombotic events, such as venous thrombosis or myocardial infarction. In patients with hemophilia A... 

In 14 clinical trials of prothrombin complex concentrates for reversal of oral anticoagulation therapy, seven of 460 patients (1.5%) had thrombotic events, three thrombotic strokes, two cases of deep venous thrombosis, and two non-Q-wave myocardial infarctions [31 ]. However, in 40 patients taking oral anticoagulants, who needed cardiopulmonary bypass surgery, and of whom 20 were treated with prothrombin complex concentrates, no thrombotic events occurred [35 ]. 

Hematologic Historically, there was concern that prothrombin complex concentrates were associated with thrombotic events such as stroke, myocardial infarction, pulmonary embolism, deep venous thrombosis, and disseminated intravascular coagulation. These events resulted mainly from the use of prothrombin complex concentrates as source of factor IX in patients with hemophilia B, and in particular after surgery, but the reported incidence is low and there is considerable evidence that the risk of thrombosis has been minimized with current prothrombin complex concentrates by reduced use of activated factors and the... 

Recombinant human erythropoietin (rHuEpo) may increase the risk of thrombosis (201). It has been reported that patients with carcinoma of the cervix who received chemotherapy and rHuEpo have an increased risk of symptomatic venous thrombosis (201). In clinical trials where the maintenance hematocrit was 3% on PROCRIT clotting of the arteriovenous shunts occurred at an annual rate of about 0.25 events per patient per year. However, other thrombotic conditions such as cerebrovascular events, transient ischemic attacks, myocardial infarction, or pulmonary embolism occurred at a rate of 0,04 events per patient per year (202). In a separate study of I, I I I untreated patients on hemodialysis, clotting of arteriovenous shunts occurred at a rate of 0.5 events per patient per year. In patients with chronic renal failure on hemodialysis who also had congestive heart failure, ischemic heart disease and venous thrombosis were increased in patients who were treated with PROCRIT targeted to a hematocrit level of 42 3% compared to those targeted to 30 3% (202). It has also been reported... 

Twenty-five percent ofthrombophilic patients develop thrombosis at unusual sites resulting in cerebral venous thrombosis, mesenteric vein thrombosis, hepatic venous thrombosis, retinal vein thrombosis, purpura fulminans, splenic vein thrombosis, portal vein thrombosis, renal vein thrombosis, or axillary vein thrombosis. The thrombotic disorders may involve inflammatory factors that contribute to the vascular deficit. In addition, embolic events also play a role in the development of these thrombotic complications. 

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