AHA: Renal artery stenting proves futile in CORAL trial

Renal artery stenting failed to offer incremental benefit over medical management for patients with renal artery stenosis and hypertension or chronic kidney disease in the CORAL trial. Results were published online Nov. 15 in the New England Journal of Medicine and simultaneously presented at the American Heart Association scientific session in Dallas.

The CORAL (Cardiovascular Outcomes in Renal Atherosclerotic Lesions) trial was designed to mitigate shortcomings in previous studies that had been criticized for enrolling patients with mild renal artery stenosis. In particular, it assessed clinical outcomes and required a renal artery stenosis of at least 60 percent and less than 80 percent of the diameter of the artery for inclusion.

“If stenting prevents the progression of kidney disease and lowers blood pressure, it has the potential to prevent serious health consequences, including adverse cardiovascular and renal events,” wrote lead author Christopher J. Cooper, MD, of the University of Toledo in Ohio. “In contrast, if stenting confers neither of these benefits, it is likely to incur substantial cost without a public health advantage.”

CORAL investigators enrolled 947 patients between May 16, 2005, and Jan. 30, 2010, who had atherosclerotic renal artery stenosis and either hypertension, chronic kidney disease or both. Patients were randomized to the stenting and medical therapy group (467 patients receiving the Cordis Palmaz Genesis stent) or medical therapy only group (480 patients prescribed an ARB with or without a thiazide-type diuretic, amlodipine, antiplatelet therapy, atorvastatin and guideline-derived diabetes management).  

The primary endpoint was a major cardiovascular or renal event, which they defined as the composite of death from cardiovascular or renal causes, MI, hospitalization for congestive heart failure, progressive renal inefficiency or a need for renal-replacement therapy.

The two groups had similar characteristics at baseline. The rate of the primary endpoint was 35.1 percent in the stenting group and 35.8 percent in the medical therapy group at a median follow-up of 43 months. There also were no significant differences in the rates for the component endpoints. Both groups increased the number of medications prescribed and the stenting group experienced a modest decrease in systolic blood pressure. The results remained consistent in subgroup analyses.

Cooper et al wrote that compared with medical therapy, renal artery stenting offered no incremental benefit. They declared medical therapy the preferred strategy for most patients with atherosclerotic renal artery stenosis.

Patients under the high-quality medical management approach used in CORAL “had remarkably good cardiovascular and renal outcomes, despite their advanced age and high rates of hypertension, diabetes, chronic kidney disease, and other co-existing cardiovascular conditions,” they wrote.

In an accompanying editorial, John A. Bittl, MD, of Munroe Regional Medical Center in Ocala, Fla., wrote that CORAL and previous trials that also found no advantage with renal artery stenting give clear evidence that stenting is futile in patients with atherosclerotic renal artery stenosis. He added that the results suggest but don’t prove that the drugs used in the medical therapy protocol offered these patients benefits.