Filters often used to stop clots without evidence

By Genevra Pittman NEW YORK (Reuters Health) – Some hospitals insert filters into the blood vessels of more than one-third of their patients with clots that may travel to the lungs, despite a lack of evidence they save lives, according to a new study. The filters, made of metal wires, are recommended based on theories about how they work for patients with a so-called venous thromboembolism who can’t take anti-clotting drugs. But they are sometimes used on other people with blood clots, as well. …