Question

A 45 year old lady with acute ileofemoral DVT:
Discuss catheter directed thrombolysis (CDT) - Technique, indication, complications and studies on CDT.

Hint:

CDT is effective for restoring venous flow and preventing long-term complications in patients with severe DVT, but its risks, especially bleeding, must be carefully managed.

Answer 1

Step 1: Technique:
Catheter-directed thrombolysis (CDT) is a minimally invasive procedure used to treat acute DVT, particularly in the ileofemoral veins. The technique involves the insertion of a catheter directly into the thrombus, allowing for localized delivery of thrombolytic agents (such as alteplase or urokinase). The catheter may be placed using fluoroscopic guidance, and sometimes, mechanical thrombectomy devices are used in combination with thrombolytic therapy.
Step 2: Indications:
CDT is indicated in patients with: - Severe Symptoms: Including swelling, pain, and risk of post-thrombotic syndrome.
- Extensive Thrombosis: Involving the ileofemoral veins or patients who are at high risk for complications such as pulmonary embolism.
- Failure of Anticoagulation: In cases where standard anticoagulation therapy fails to provide adequate symptom relief.

Step 3: Complications:
Complications of CDT can include: - Bleeding: From either the catheter insertion site or from systemic anticoagulation.
- Infection: At the catheter site or within the vein.
- Recurrent thrombosis: In cases where thrombus is not adequately cleared.
- Pulmonary Embolism: If thrombolysis or thrombectomy dislodges clot fragments.

Step 4: Studies on CDT:
Several studies have shown that CDT improves symptoms and quality of life in patients with acute iliofemoral DVT. The most notable studies include: - The CAVENT Trial: Which demonstrated improved outcomes with CDT compared to anticoagulation alone in patients with acute DVT.
- The ATTRACT Trial: Focused on the long-term benefits of CDT in terms of reducing post-thrombotic syndrome, though some studies have raised concerns about the risk-benefit profile.