It sounds like science fiction: A stent made of bioabsorbable plastic simply dissolves back into the bloodstream within a year or two after its work opening an artery is done—similar to the way sutures or bone screws are ultimately absorbed.
  Stent designers have spent decades pursuing this goal, with little success. But drug and medical devices company Abbott Laboratories is finally showing progress. Abbott's new stent, called Absorb, is made of polylactic acid and coated with a drug called Everolimus. The water in the artery wall eventually breaks down the polylactic acid into lactic acid, a naturally produced substance. That lactic acid is then absorbed into the body as carbon dioxide and water, leaving nothing behind.
  Absorb's human trials in 30 patients showed positive results at the nine-month mark, with a low rate of major cardiovascular events and no stent thrombosis, a rare but often fatal clotting within the stent itself years after insertion. "If I could provide a fully bioabsorbable, drug-coated stent that works as well as a metallic one, it's a no-brainer," says John M. Capek, Abbott's executive vice president for medical products...