A common and painful complication of deep vein thrombosis can be helped in much the same way doctors now treat many heart attacks, a new study says.
Placing a stent to open and strengthen a damaged vein can reduce the severity of post-thrombotic syndrome, an aftereffect that can occur within two years of a person’s initial bout with deep vein thrombosis, researchers reported April 13 in The New England Journal of Medicine.
“These results provide a strong foundation for clinicians as we work to deliver safe, effective and durable treatment options for people living with the long‑term consequences of deep vein thrombosis,” lead researcher Dr. Suresh Vedantham, a professor of radiology and surgery at the University of Washington in Seattle, said in a news release.
Deep vein thrombosis is a serious condition in which a blood clot forms in the deep veins, most often in one of the legs. More than 300,000 Americans are diagnosed with this condition each year, researchers said in background notes.
If the clot breaks loose, it can travel to the lungs and cause a life-threatening pulmonary embolism. Together, these two conditions cause as many as 100,000 deaths a year in the U.S., researchers said.
Unfortunately, a person’s risk continues long after their deep vein thrombosis subsides.
An estimated 40% of patients wind up with post-thrombotic syndrome, where the damage caused by the initial event prevents their veins from working properly, researchers said. The place where the blockage occurred develops scar tissue, restricting blood flow in the legs.
Symptoms of post-thrombotic syndrome include leg pain, swelling, skin discoloration, impaired mobility and reduced quality of life, researchers said. In severe cases, difficult-to-treat open sores might develop on the skin below the blocked vein.
“We see a lot of patients who have moderate or severe post-thrombotic syndrome and have a tough time conducting their daily activities and maintaining a good quality of life,” Vedentham said. “Many patients are unable to walk without pain or work productively.”
Current treatments for post-thrombotic syndrome involve compression stockings to reduce swelling and blood thinners to prevent new clots from forming, Vedentham said.
However, these treatments don’t address the vein damage causing the problem, and thus provide no long-term relief, Vedentham said.
For the new study, researchers tested whether re-opening the damaged vein and restoring blood flow would reduce patients’ symptoms.
The team recruited 225 patients at 29 hospitals across the U.S. whose deep vein thrombosis had resulted in blockage of a major vein in the pelvis, the iliac vein. As a result, the patients had suffered substantial disability.
Patients were randomly selected to either receive a stent alongside standard treatment with compression and blood thinners, or standard treatment alone.
A stent is a mesh tube that can be inserted into damaged blood vessels to prop them open and reinforce them. Stenting is also used to treat heart attacks caused by clogged arteries.
At the start of the study, 93% of all patients met the clinical criteria for severe post-thrombotic syndrome, researchers said.
Six months later, only 40% of patients who received the stent still had severe symptoms, compared to 61% of patients in the standard care group, the study showed.
Patients with stents also reported improved overall quality of life, scoring 14 points higher on a 100-point quality-of-life scale than those who received standard care.
“Post-thrombotic syndrome can be life‑altering, yet we’ve had very few effective treatment options,” said senior researcher Sameer Parpia, an associate professor of oncology and health research methods, evidence and impact at McMaster University in Ontario, Canada.
“This trial provides clear evidence that targeted therapy can make a meaningful difference for patients living with this condition,” Parpia said in a news release.
These results also were presented Monday at the Society of Interventional Radiology’s annual meeting in Toronto, Canada.