When Is Renal Artery Revascularization Beneficial?

Flash pulmonary edema is a high-risk indication for renal artery revascularization, but declining kidney function and refractory hypertension may not be, reports a study in the American Journal of Kidney Diseases.

The researchers analyzed one hospital’s experience of 467 patients with renal artery stenosis of 50 percent or greater, treated according to clinical presentation and physician and patient preference. Flash pulmonary edema was present in 7.8 percent of patients, refractory hypertension in 24.3 percent, and rapidly declining kidney function in 9.7 percent. Treatment and outcomes were compared for patients with versus without these high-risk characteristics.

Renal artery revascularization was performed in 32 percent of patients with flash pulmonary edema, 28 percent with rapidly declining kidney function, and 28 percent with refractory hypertension. At a median 3.8 years of follow-up, 55 percent of patients had died, 33 percent had a cardiovascular (CV) event, and 18 percent had ESRD.

In patients treated medically, flash pulmonary edema was associated with an increased risk of death and CV events: hazard ratio 2.2 and 3.1, respectively. Rapidly declining kidney function and refractory hypertension were not associated with increased risk of adverse outcomes. Among patients with flash pulmonary edema, the risk of death was lower for those undergoing revascularization (HR 0.4) in comparison with medical management, but there was no difference in CV events or ESRD.

Revascularization did not reduce adverse outcomes in patients with rapidly declining kidney function or refractory hypertension. For the 31 patients who had both of these high-risk characteristics, revascularization was associated with a reduced risk of death (HR 0.15) and CV events (HR 0.23).

Recent studies have questioned the use of revascularization for patients with renovascular atherosclerosis and stable kidney disease. However, these findings may not apply to patients with high-risk presentations.

The new study suggests that revascularization is indicated for patients with flash pulmonary edema, consistent with current guidelines. More research is needed to determine the benefit of revascularization for patients with rapidly declining kidney function plus refractory hypertension [Ritchie J, et al. High-risk clinical presentations in atherosclerotic renovascular disease: prognosis and response to renal artery revascularization. Am J Kidney Dis 2014; 63:186–197].

March 2014 (Vol. 6, Number 3)