As expected, the researchers who conducted the study at the University of Vienna, Austria, do not advocate smoking. But the findings suggest that increasing the level of carbon monoxide in the blood stream following angioplasty and stent placement within the lower limb arteries may help prevent restenosis.
"Smokers exhibit a higher blood concentration of carbon monoxide, a potent anti-inflammatory agent known to dilate blood vessels," said the study's lead author, Martin Schillinger, M.D., associate professor of internal medicine at the University of Vienna Medical School. "Carbon monoxide can inhibit the growth of smooth muscle cells within the artery wall, which is a key factor in the restenosis process."
In peripheral artery disease (PAD), a narrowing or blockage in the arteries causes an insufficient flow of oxygenated blood to the arms or legs. Interventional radiologists treat PAD with angioplasty, a minimally invasive procedure in which a balloon-tipped catheter-a thin, plastic tube-is threaded to the site of the blockage and inflated. Often the radiologist will place a wire mesh cylinder called a stent inside the artery to help prevent it from collapsing or becoming clogged again.
"Angioplasty and stent placement to repair obstructions in lower limb vessels have a high rate of restenosis," Dr. Schillinger said. "Up to 60 percent of patients who undergo endovascular interventions for PAD will experience restenosis and will need to repeat the treatment within a year."
Contact: Maureen Morley
Radiological Society of North America