LITERATURE HIGHLIGHTS: Renal Artery Stenting Studied in ARVD and CKD Patients

January 1, 2010—In a study published in Catheterization and Cardiovascular Interventions, Philip A. Kalra, MD, et al aimed to investigate whether differences in outcomes after revascularization compared to medical management might be observed in atheromatous renovascular disease (ARVD) patients if stratified by their advanced chronic kidney disease (CKD) classes (2010;75:1–10). The background of the study is that approximately 16% of all patients who present with ARVD in the United States undergo revascularization, and patients with CKD historically have been considered least likely to show renal function improvement or survival.

According to the investigators, two prospective cohorts, a United Kingdom center with a traditionally conservative approach and a German center that undertook a proactive revascularization approach, were compared. An improvement in renal function was defined as > 20% renal improvement at 1-year follow-up. To improve validity and comparability, revascularized patients in the United Kingdom center were also used within analyses.

The investigators reported that 347 (United Kingdom conservative group), 89 (United Kingdom revascularized group), and 472 (German center) patients were included in the analysis. When subdivided by CKD stage, patient ages between the two centers were comparable. Improvements in renal function were observed in twice as many patients who underwent revascularization as compared to medical treatment, particularly in the latter CKD stages (15.2% [German revascularization] vs 0% in CKD 1–2; 12.2% [United Kingdom] and 32.8% [German revascularization] vs 14.1% in CKD 3; and 53.1% and 53.8% vs 28.3% in patients with CKD 4–5). The improvements in eGFR (estimated glomerular filtration rate) were 10.2 (16) and 8.1 (12.5) mL/min/year in the German and United Kingdom revascularized groups, respectively, versus -0.05 (6.8) mL/min/year in the medical cohort in CKD 4 to 5. Improvements in blood pressure control were noted at 1 year overall and within each CKD category. Multivariate analysis revealed that revascularization independently reduced the risk of death by 45% in all patients combined (relative risk, 0.55; P = .013).

The investigators concluded that although this study has significant methodological limitations, it shows that percutaneous renal revascularization can improve renal function in advanced CKD (stages 4–5) and that this can provide a survival advantage in prospective analysis.