From the Guidelines
For acute pulmonary embolism (PE), unfractionated heparin infusion is generally preferred over argatroban in most cases, as recommended by the 2019 ESC guidelines 1. The standard approach is to start with a heparin bolus of 80 units/kg followed by an infusion at 18 units/kg/hour, with dose adjustments to maintain aPTT at 1.5-2.5 times normal. Some key points to consider when choosing between heparin and argatroban include:
- Heparin has extensive clinical experience and established protocols for use in PE
- Heparin is reversible with protamine, which is an advantage in cases where anticoagulation needs to be quickly reversed
- Argatroban should be reserved for patients with heparin-induced thrombocytopenia (HIT) or those with a history of HIT, as recommended by the American Society of Hematology 2018 guidelines 1
- In cases where argatroban is used, it is typically dosed at 2 mcg/kg/min initially, adjusted to maintain aPTT at 1.5-3 times baseline, not exceeding 100 seconds
- Argatroban requires dose reduction in hepatic impairment since it's metabolized by the liver, while no adjustment is needed for renal dysfunction Both medications require transition to oral anticoagulants like warfarin or direct oral anticoagulants for long-term management, typically for at least 3-6 months after the acute PE episode. Key considerations for the choice of anticoagulant include:
- Patient factors such as kidney function, liver function, bleeding risk, and clinical stability
- Drug factors such as availability, cost, ability to monitor the anticoagulant effect, route of administration, and half-life
- Clinical experience and established protocols for use in PE.
From the FDA Drug Label
- 1 Heparin If argatroban is to be initiated after cessation of heparin therapy, allow sufficient time for heparin’s effect on the aPTT to decrease prior to initiation of argatroban therapy. The FDA drug label does not answer the question.
From the Research
Comparison of Argatroban and Heparin Infusion for Acute Pulmonary Embolism (PE)
- The provided studies do not directly compare Argatroban and Heparin infusion for the treatment of acute Pulmonary Embolism (PE) 2, 3, 4, 5, 6.
- However, the studies discuss the use of anticoagulants, including heparin, in the treatment of PE 2, 3, 4, 5.
- Argatroban is mentioned in one study as an alternative to heparin in a patient with heparin-induced thrombocytopenia 6.
- The studies suggest that anticoagulation is the mainstay of treatment for PE, and that direct oral anticoagulants may be as effective and safe as conventional anticoagulation in patients without haemodynamic compromise 2, 3.
- Thrombolysis is recommended for patients with PE and systolic blood pressure lower than 90 mm Hg, or for those with significant hypoxemia or hypotension due to proven pulmonary embolism 2, 4, 5.
Treatment Options for Acute Pulmonary Embolism
- Initial therapy for PE includes low-molecular-weight heparin, fondaparinux, or unfractionated heparin 5.
- Long-term treatment typically involves vitamin-K antagonists (VKAs) 5.
- New oral anticoagulants, such as factor IIa and factor Xa inhibitors, are being investigated as alternative treatment options 5.
- The duration of anticoagulation therapy depends on the type of PE and the balance between the risks of recurrent PE, major bleeding, and patient preference 5.
Considerations for Anticoagulation Therapy
- Patients with a malignancy may require treatment with low-molecular-weight heparin during the first 6 months after diagnosis of PE 5.
- In patients with heparin-induced thrombocytopenia, alternative anticoagulants such as argatroban may be used 6.
- Clinicians should be aware that coagulation parameters may remain elevated longer than expected after argatroban discontinuation in certain patients taking concomitant warfarin, particularly those with liver dysfunction and obesity 6.