Update: This story was updated to include additional comments from principal investigator Suresh Vedantham.
An NIH-funded trial found that most patients suffering from deep vein thrombosis (DVT) should still be treated with the standard-of-care clot-busting drugs. But some patients, who are more likely to develop post-thrombotic syndrome (PTS), would benefit from interventional treatment in addition to blood thinners, the study found.
DVT refers to a clot forming in one of the body’s deep veins, usually in the legs. It may cause pain and swelling in the leg, but there is also a risk the clot will break off, travel to the lungs and block blood flow, according to the NIH. DVT patients are usually treated with anticoagulant drugs and compression stockings.
The ATTRACT study involved 692 patients with acute DVT in their femoral, common femoral and/or iliac veins, according to a Society of Interventional Radiology statement. The study was presented on Monday at the SIR’s annual meeting and was funded primarily by the NIH, with support from SIR and Boston Scientific, BSN Medical, Medtronic and Genentech.
The patients were randomly divided into two treatment groups. The first received blood thinners alongside interventional treatment, known as pharmacomechanical catheter-directed thrombolysis (PCDT), while the control group was treated with anticoagulants alone.
Patients who received both treatments were 25% less likely to develop moderate to severe PTS than were patients in the control group, the study found. PTS symptoms range from chronic leg pain and swelling to skin ulcers and disability. While both groups had roughly the same rate of PTS, patients with the largest blood clots, known as iliofemoral DVT, have the highest risk of developing PTS and so are most likely to benefit from the combination treatment.
“These findings allow healthcare professionals to make better decisions as to who may benefit from PCDT, ensuring that patient care teams deliver the best care, while reducing harm from unnecessary treatments,” said principal investigator Suresh Vedantham, M.D., a professor of radiology and surgery at the Mallinckrodt Institute of Radiology at the Washington University School of Medicine, in the statement.
This study provides the first "solid" information that can guide DVT treatment, Vedantham said. In the past, doctors' decisions on treating DVT were based and opinion and consensus. Now, there is data that quantifies the benefits and risks of using an invasive procedure to break up the clot, he said.