cardiovascular disorders
Deep Venous Thrombosis (DVT)
Treatment of Deep Venous Thrombosis
Anticoagulation Sometimes inferior vena cava filter, thrombolytic therapy, or surgery Treatment is aimed primarily at Prevention and secondarily at symptom relief and prevention of DVT recurrence, General supportive measures include pain control with analgesics, which may include short (3- to 5-day) courses of a nonsteroidal anti-inflammatory drug (NSAID). Extended treatment with NSAIDs andaspirinshould be avoided because their antiplatelet effects may increase the risk of bleeding complications. In addition, elevation of legs (supported by a pillow or other soft surface to avoid venous compression) is recommended during periods of inactivity. Patients may be as physically active as they can tolerate; there is no evidence that early activity increases risk of clot dislodgement and PE and may help to reduce the risk of the post-thrombotic syndrome. (For details on medications and their complications, see Medications for Deep Venous Thrombosis ) Almost all patients with DVT are treated with anticoagulants ( Treatment references , Some patients are initially given an injectableheparin(typically low molecular weight) for 5 to 7 days, followed by longer term treatment with an oral agent.Warfarin, if used, is started within 24 hours after the start of the injectableheparin. Althoughheparinacts rapidly and provides immediate anticoagulation,warfarintakes about 5 days to achieve a therapeutic effect; hence,heparinis required for 5 to 7 days. For patients who are to startedoxaban(an oralfactor Xainhibitor) ordabigatran(an oral directthrombininhibitor), the oral agent is started after 5 days of injectableheparin. Alternatively, anticoagulation may be initiated immediately with selected direct oral anticoagulants (rivaroxabanorapixaban) without first giving an injectableheparin. Startingrivaroxabanorapixabanwithoutheparinis justified based on results of clinical trials.Fondaparinux, a parenteralfactor Xainhibitor, is sometimes substituted for low molecular weightheparinand can also be used to treat acute DVT. For selected patients (eg, with extensive iliofemoral DVT or cancer), continued treatment with a low-molecular-weightheparinrather than switching to an oral agent may be preferred. Inadequate anticoagulation in the first 24 to 48 hours may increase risk of recurrence or of PE. Acute DVT can be treated on an outpatient basis unless severe symptoms require parenteral analgesics, other disorders preclude safe outpatient discharge, or other factors (eg, functional, socioeconomic) might prevent the patient from adhering to prescribed treatments. An IVC filter may help prevent PE in patients with lower extremity DVT who have contraindications to anticoagulant therapy or in patients with recurrent DVT (or emboli) despite adequate anticoagulation. An IVC filter is placed in the inferior vena cava just below the renal veins via catheterization of an internal jugular or femoral vein. Some IVC filters are removable and can be used temporarily (eg, until contraindications to anticoagulation subside or resolve). IVC filters reduce the risk of acute embolic complications but can have longer-term complications (eg, venous collaterals can develop, providing a pathway for emboli to circumvent the filter) There is also an increased risk of recurrent DVT). Also, IVC filters can dislodge or become obstructed by a clot. Thus, patients with recurrent DVT or nonmodifiable risk factors for DVT may still require anticoagulation despite the presence of an IVC filter. A clotted filter may cause bilateral lower extremity venous congestion (including acute phlegmasia cerulea dolens), lower body ischemia, and Acute Kidney Injury (AKI) . Treatment for a dislodged filter is removal, using angiographic or, if necessary, surgical methods. Despite widespread use of IVC filters, efficacy in preventing PE is understudied and unproven ( 60 years with extensive iliofemoral DVT who have evolving or existing limb ischemia (eg, phlegmasia cerulea dolens) and do not have risk factors for bleeding ( Treatment references ). Catheter-directed thrombolysis has largely replaced systemic administration when used for DVT. Surgery is rarely needed. However, thrombectomy, fasciotomy, or both are mandatory for phlegmasia alba dolens or phlegmasia cerulea dolens unresponsive to thrombolytics to try to prevent limb-threatening gangrene. 1.Ortel TL, Neumann I, Ageno W, et al: American Society of Hematology 2020 guidelines for management of venous thromboembolism: treatment of deep vein thrombosis and pulmonary embolism.Blood Adv4(19):4693-4738, 2020. doi: 10.1182/bloodadvances.2020001830 2.Stevens SM, Woller SC, Kreuziger LB, et al: Antithrombotic Therapy for VTE Disease: Second Update of the CHEST Guideline and Expert Panel Report [published correction appears inChest2022 Jul;162(1):269].Chest160(6):e545-e608, 2021. doi:10.1016/j.chest.2021.07.055 3.Turner TE, Saeed MJ, Novak E, Brown DL: Association of Inferior Vena Cava Filter Placement for Venous Thromboembolic Disease and a Contraindication to Anticoagulation With 30-Day Mortality.JAMA Netw Open1(3):e180452, 2018. Published 2018 Jul 6. doi:10.1001/jamanetworkopen.2018.0452 4.Kearon C, Akl EA, Comerota AJ, et al. Antithrombotic therapy for VTE disease: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines [published correction appears inChest2012 Dec;142(6):1698-1704].Chest2012;141(2 Suppl):e419S-e496S. doi:10.1378/chest.11-2301 