Catheter-directed thrombolysis is a procedure designed to rapidly break up a blood clot, restore blood flow within the vein and potentially preserve valve function to minimize the risk of post-thrombotic syndrome. During the procedure, an interventional radiologist inserts a catheter into the popliteal (located behind the knee) or other leg vein and threads it into the vein containing the clot, using imaging guidance. The catheter tip is placed into the clot and a “clot busting” drug is infused directly to the thrombus (clot). The fresher the clot, the faster it dissolves, generally one to two days.
Any narrowing in the vein that might lead to future clot formation can be identified by venography, an imaging study of the veins, and treated by the interventional radiologist with a balloon angioplasty or stent placement. Clinical resolution of pain and swelling, and restoration of blood flow in the vein is greater than 85 percent with the catheter-directed technique.
In patients for whom this is not appropriate and blood thinners are not medically appropriate, an interventional radiologist can insert a vena cava filter, a small device that functions like a catcher’s mitt to capture blood clots but allow normal blood to pass.