American Society of Hematology 2020 guidelines for management of venous thromboembolism: treatment of deep vein thrombosis and pulmonary embolism

Abstract

Background: Venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolism (PE), occurs in ∼1 to 2 individuals per 1000 each year, corresponding to ∼300 000 to 600 000 events in the United States annually.

Objective: These evidence-based guidelines from the American Society of Hematology (ASH) intend to support patients, clinicians, and others in decisions about treatment of VTE.

Methods: ASH formed a multidisciplinary guideline panel balanced to minimize potential bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline development process, including updating or performing systematic evidence reviews. The panel prioritized clinical questions and outcomes according to their importance for clinicians and adult patients. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess evidence and make recommendations, which were subject to public comment.

Results: The panel agreed on 28 recommendations for the initial management of VTE, primary treatment, secondary prevention, and treatment of recurrent VTE events.

Conclusions: Strong recommendations include the use of thrombolytic therapy for patients with PE and hemodynamic compromise, use of an international normalized ratio (INR) range of 2.0 to 3.0 over a lower INR range for patients with VTE who use a vitamin K antagonist (VKA) for secondary prevention, and use of indefinite anticoagulation for patients with recurrent unprovoked VTE. Conditional recommendations include the preference for home treatment over hospital-based treatment for uncomplicated DVT and PE at low risk for complications and a preference for direct oral anticoagulants over VKA for primary treatment of VTE.

Figure 1.

Time frame of the decisions. Initial management (yellow box) spans the first 5 to 21 days following diagnosis of a new VTE and includes issues concerning whether the patient can be treated at home or requires admission to the hospital, use of thrombolytic therapy, whether an IVC filter needs to be placed, and initial anticoagulant therapy. Primary treatment continues anticoagulant therapy for 3 to 6 months total and represents the minimal duration of treatment for the VTE. After completion of primary treatment, the next decision concerns whether anticoagulant therapy will be discontinued or if it will be continued for secondary prevention of recurrent VTE. Typically, secondary prevention is continued indefinitely, although patients should be reevaluated on a regular basis to review the benefits and risks of continued anticoagulant therapy. Our choice of terminology reflects the distinct clinical intentions of the different phases of VTE management, linking them to important clinical decisions addressed in the guidelines, rather than using terms reflecting the relative duration of therapy.

Figure 2.

Relationships of Recommendations 12 to 22 with primary treatment and secondary prevention phases of VTE treatment. Recommendations 12 to 14 address the duration of the primary treatment phase of therapy. Recommendations 15 to 17 address strategies to decide whether to discontinue anticoagulant therapy or continue with secondary prevention. Recommendations 18 to 22 address which patients should receive secondary prevention and with what antithrombotic therapies.