Stents no help for patients with narrow kidney arteries

Using stents to open up kidney arteries is commonly done in patients with atherosclerotic renovascular disease, but the procedure provides no benefit, according to a paper being presented at the American Society of Nephrology's 41st Annual Meeting and Scientific Exposition in Philadelphia, Pennsylvania.

Patients with renovascular disease due to atherosclerosis have narrowed blood vessels leading to their kidneys. The condition is relatively common in the general population, and its prevalence increases with age. While revascularization with stents is often performed in an attempt to correct atherosclerotic renovascular disease, there is no reliable evidence that the procedure - which is not without certain risks - improves patients' kidney function or positively impacts other health outcomes such as blood pressure and survival.

The Angioplasty and Stenting for Renal Artery Lesions (ASTRAL) trial was designed to investigate this issue. Keith Wheatley and his colleagues, including lead nephrologist Phil Kalra, MD, and lead interventional radiologist, Professor Jon Moss, recruited more than 800 patients with atherosclerotic renovascular disease from the United Kingdom and Australasia to the ASTRAL trial. Patients in the study were randomized to undergo revascularization plus medical treatment or medical treatment alone.

The trial's investigators measured outcomes, including kidney function, blood pressure, major kidney and cardiovascular events, and death, at a span of five years. Unfortunately, the study revealed no clinically worthwhile benefits associated with revascularization on any of the outcomes that were studied.

While investigators hope that large clinical trials such as ASTRAL will show that a potentially promising intervention is effective and improves patient outcomes, it is often the case that the treatment is shown not to have any clinically worthwhile benefits, said Wheatley. "Such 'negative' trials are nevertheless very useful and enable treatments that do not work, and which may have risks associated with them, to be eliminated from practice, thereby ensuring patient safety and enabling resources to be better used elsewhere," he added.

Professor Wheatley and his colleagues hope that the results from the ASTRAL study - the largest randomized trial to date in patients with atherosclerotic renovascular disease - will lead to important changes in the way patients with this disease are treated. The clinical trial's findings indicate that these individuals should not be subjected to unnecessary revascularization procedures.