From the Guidelines
Management of a thrombus in transit through a patent foramen ovale (PFO) requires immediate intervention with anticoagulation and consideration for surgical or catheter-based removal, with a focus on preventing paradoxical embolization and reducing the risk of stroke or myocardial infarction. The initial management should include immediate therapeutic anticoagulation with intravenous unfractionated heparin, as recommended by the American Heart Association 1. Urgent cardiothoracic surgical consultation should be obtained for potential surgical thrombectomy, particularly for large, mobile thrombi with high risk of embolization. In cases where surgery is contraindicated, catheter-based retrieval may be considered. Thrombolytic therapy with tissue plasminogen activator (tPA) is generally avoided due to risk of thrombus fragmentation and systemic embolization.
After acute management, long-term anticoagulation with direct oral anticoagulants (e.g., apixaban 5mg twice daily) or warfarin (target INR 2-3) is recommended for at least 3-6 months, as suggested by the Canadian Stroke Best Practice Recommendations 1. Definitive PFO closure should be considered after resolution of the acute event to prevent recurrence, particularly in carefully-selected patients aged 60 years or younger with an unexplained embolic stroke event who are found to have a PFO and who do not require chronic anticoagulant therapy for another reason. The benefits and risks of PFO closure, including the risk of procedural complications such as atrial fibrillation, should be carefully weighed and discussed with the patient.
Some key points to consider in the management of a thrombus in transit through a PFO include:
- Immediate anticoagulation with intravenous unfractionated heparin
- Urgent cardiothoracic surgical consultation for potential surgical thrombectomy
- Consideration of catheter-based retrieval in cases where surgery is contraindicated
- Avoidance of thrombolytic therapy with tPA due to risk of thrombus fragmentation and systemic embolization
- Long-term anticoagulation with direct oral anticoagulants or warfarin for at least 3-6 months
- Definitive PFO closure after resolution of the acute event to prevent recurrence, in carefully-selected patients.
From the Research
Management of Thrombus in Transit through PFO
The management of a thrombus in transit through a patent foramen ovale (PFO) is a complex issue, with various treatment options available. The choice of treatment depends on several factors, including the patient's overall health, the size and location of the thrombus, and the presence of any underlying medical conditions.
- Surgical Treatment: Surgery is considered a viable option for patients with a thrombus in transit through a PFO, particularly those who are not at high surgical risk 2, 3, 4, 5. Surgical thrombectomy with closure of the PFO can be an effective treatment, with good outcomes reported in several case studies.
- Anticoagulation Therapy: Anticoagulant treatment is also a commonly used approach for managing thrombus in transit through a PFO, particularly in patients with comorbidities who are at high surgical risk or have small PFOs 2, 4, 6. Anticoagulation therapy can help prevent further thrombus formation and reduce the risk of systemic embolization.
- Thrombolysis: Thrombolysis is another treatment option, although it is associated with a higher mortality rate compared to surgery and anticoagulation therapy 2. Thrombolysis may be considered in patients with severe pulmonary embolism or those who are not candidates for surgery.
Factors Influencing Treatment Choice
Several factors can influence the choice of treatment for thrombus in transit through a PFO, including:
- Patient's Overall Health: The patient's overall health and presence of any underlying medical conditions can affect the choice of treatment.
- Size and Location of the Thrombus: The size and location of the thrombus can impact the treatment approach, with larger thrombi potentially requiring surgical intervention.
- Presence of Comorbidities: The presence of comorbidities, such as atrial fibrillation or persistent atrial septal aneurysm, can increase the risk of thrombus formation and influence treatment choices 6.