Updates to the American College of Chest Physicians (CHEST) clinical practice guideline on antithrombotic therapy in venous thromboembolism (VTE) include recommendations on several Population, Intervention, Comparator, Outcome (PICO) questions covering a wide spectrum of VTE-related antithrombotic management scenarios. The updated guideline recommendations, summarized here, were published in a recent edition of Chest.
“Whether to Treat” Recommendations
The first PICO question presented in the updated guideline pertained to whether anticoagulant therapy should be used in patients with isolated distal deep vein thrombosis (DVT). In the accompanying evidence-based guidance statement, the CHEST panel suggests the use of serial imaging of the deep veins for 2 weeks vs anticoagulation in patients with acute isolated distal DVT of the leg who lack severe symptoms or risk factors for extension. In contrast, anticoagulation is suggested over serial imaging in patients with severe symptoms or risk factors for extension.
The guideline recommends against anticoagulation in patients with acute isolated distal DVT of the leg who are treated with serial imaging if the thrombus does not extend. Anticoagulation is suggested in cases where the thrombus extends but is confined to the distal veins. Additionally, anticoagulation is also recommended if the thrombus extends into the proximal veins.
For patients who have subsegmental pulmonary embolism (PE) and absent proximal DVT in the legs as well as low risk for recurrent VTE, the guideline suggests clinicians employ clinical surveillance vs anticoagulation. However, anticoagulation is recommended over surveillance in similar patients with a high risk of recurrent VTE.
The updated CHEST guideline also strongly recommends the provision of anticoagulation for the first 3 months (treatment phase) over no anticoagulant therapy in patients with cerebral vein or cerebral venous sinus thrombosis. According to the guideline authors, the recommendation applies to patients with or without CVT-related intracranial hemorrhage.
Interventional and Adjunctive Treatments
Anticoagulant monotherapy is suggested over interventional thrombolytic, mechanical, or pharmacomechanical therapy in patients with acute DVT of the leg. Systemically administered thrombolytic therapy is suggested over no systemically administered thrombolytic therapy in patients with acute PE associated with hypotension without a high bleeding risk.
The guideline committee made a strong recommendation against systemically administered thrombolytic therapy in the majority of patients with acute PE that is not associated with hypotension. Additionally, the guideline suggests systemically administered thrombolytic therapy in certain patients with acute PE who show signs of deterioration after anticoagulant therapy initiation but who have not developed hypotension and who continue to have “an acceptable bleeding risk.”
In terms of the setting of initial anticoagulation, the updated CHEST guideline recommends outpatient treatment over hospitalization in patients with low-risk PE but only if there is adequate medication access, an ability to access outpatient care, and adequate home circumstances. This strong recommendation was made based on evidence showing home treatment provides greater convenience and is less costly for most patients.
According to the guideline, outpatient treatment of acute PE is suitable for patients who meet all the following criteria: clinically stable with good cardiopulmonary reserve; lack contraindications (eg, recent bleeding, severe renal or liver disease, or severe thrombocytopenia); compliant with therapy; and subjective reports of feeling well enough to receive treatment at home.
A strong recommendation was made for the use of apixaban, dabigatran, edoxaban, or rivaroxaban over a vitamin K antagonist (VKA) as the treatment-phase anticoagulant therapy in patients with DVT of the leg or PE.
Direct Oral Anticoagulants (DOACs)
An oral Xa inhibitor — such as apixaban, edoxaban, or rivaroxaban — is strongly recommended over low-molecular-weight heparin for the initiation and treatment phases of treatment in patients with acute VTE in the setting of cancer. Additionally, an adjusted-dose VKA is suggested over DOAC therapy during the treatment phase in patients with confirmed antiphospholipid syndrome who are receiving anticoagulant therapy.
Duration of Anticoagulation in Acute VTE
In the treatment phase, the guideline makes a strong recommendation for a 3-month treatment phase of anticoagulation in patients with acute VTE who do not have a contraindication to such a regimen.
In regard to extended-phase therapy, the guideline makes a strong recommendation against extended-phase anticoagulation in patients with VTE who receive a diagnosis in the setting of a major transient risk factor. The guideline also suggests against the provision of extended-phase anticoagulation in patients with VTE who are diagnosed in the setting of a minor transient risk factor.
Among patients with unprovoked VTE or VTE provoked by persistent risk factor, the guideline recommends the use of extended-phase anticoagulation with a DOAC. The guideline also suggests offering extended-phase anticoagulation with a VKA to patients with VTE who are diagnosed in the absence of transient risk factor and who cannot receive a DOAC.
The use of reduced-dose apixaban or rivaroxaban is suggested over full-dose apixaban or rivaroxaban for patients who are offered extended-phase anticoagulation. Reduced-dose DOAC is strongly recommended over aspirin or no therapy in patients who are offered extended-phase anticoagulation. To prevent recurrent VTE, the guideline suggests the use of aspirin over no aspirin in patients with an unprovoked proximal DVT or PE who are halting anticoagulant therapy and who do not have a contraindication to aspirin.
For the routine prevention of post-thrombotic syndrome (PTS) in patients with acute DVT of the leg, the guideline suggests against the use of compression stockings. The guideline authors noted that while graduated compression stockings may reduce acute DVT-related symptoms or chronic symptoms in patients with PTS, there is a lack of evidence showing these stockings reduce the risk of PTS development. Additionally, the authors stated there is no evidence to suggest that the use of these stockings can reduce the recurrent DVT risk.
Stevens SM, Woller SC, Baumann Kreuziger L, et al. Executive summary: antithrombotic therapy for VTE disease: second update of the CHEST Guideline and Expert Panel Report. Chest. 2021;160(6):2247-2259. doi:10.1016/j.chest.2021.07.056