From the Guidelines
COVID-19 vaccine-induced pulmonary embolism (PE) should be considered a provoked PE, and the recommended duration of anticoagulation is typically 3 months, as suggested by the most recent guidelines. This classification is based on the understanding that vaccine-induced thrombotic events are triggered by a transient immune response, which is not considered a persistent risk factor for recurrent thrombosis once the acute phase has resolved 1.
The American College of Chest Physicians guidelines support this approach, recommending anticoagulation therapy for a minimum duration of three months for COVID-19 patients with proximal DVT or PE 1. Although an older guideline suggests treatment with anticoagulation for 3 months over extended therapy if there is a low or moderate bleeding risk (Grade 2B) 1, the more recent guideline specific to COVID-19 patients takes precedence in this context.
Key considerations for treatment include:
- Starting with therapeutic-dose low molecular weight heparin or direct oral anticoagulants (DOACs) like apixaban or rivaroxaban
- Reassessing patients for ongoing risk factors and bleeding risk after the initial treatment period
- Potentially considering a shorter duration of 3 months if there are no other risk factors and the PE has resolved on follow-up imaging, although this should be guided by the most recent and specific recommendations for COVID-19 vaccine-induced PE 1.
From the Research
COVID-19 Vaccine-Induced Pulmonary Embolism
- COVID-19 vaccine-induced pulmonary embolism (PE) is a rare adverse event that has been reported in some cases 2, 3, 4, 5.
- The pathophysiology of COVID-19-associated PE may differ from conventional non-COVID-19-associated PE, with endothelial activation, inflammatory reaction, and hypercoagulable state playing a role 4.
Classification of COVID-19 Vaccine-Induced PE
- COVID-19 vaccine-induced PE can be considered as a form of provoked PE, as it is triggered by a specific event (vaccination) 2, 4.
- However, the classification of COVID-19 vaccine-induced PE as provoked or unprovoked may depend on the individual case and the presence of other risk factors 6, 4.
Recommended Duration of Anticoagulation
- The recommended duration of anticoagulation for COVID-19 vaccine-induced PE is not well established, but it is generally recommended to continue anticoagulation for at least 3-6 months 6, 4.
- The decision on the duration of anticoagulation should consider both the individual risk of PE recurrence and the individual risk of bleeding 6.
- In some cases, extended oral anticoagulation of indefinite duration may be considered, especially in patients with a high risk of recurrence 6, 4.
Treatment of COVID-19 Vaccine-Induced PE
- The treatment of COVID-19 vaccine-induced PE is similar to the treatment of conventional non-COVID-19-associated PE, with anticoagulation being the mainstay of treatment 6, 4.
- Non-heparin anticoagulants, such as direct oral anticoagulants (DOACs), may be preferred over heparin due to their favorable safety profile 6, 5.
- In cases of vaccine-induced immune thrombotic thrombocytopenia (VITT), treatment with non-heparin anticoagulants and high-dose intravenous immunoglobin (IVIG) may be recommended 5.