A, Mortality incidence was 14.0% for revascularization vs 15.3% for medical therapy (P = .37). B, Hospitalization for heart failure was 9.4% vs 10.4% (P = .40); C, for stroke: 4.1% vs 5.1% (P = .30); and D, for worsening renal function: 15.3% vs 16.1% (P = .67), respectively. ASTRAL indicates Angioplasty and Stenting for Renal Artery Lesions; CORAL, Cardiovascular Outcomes in Renal Atherosclerotic Lesions; DRASTIC, Dutch Renal Artery Stenosis Intervention Cooperative; EMMA, Essai Multicentrique Medicaments vs Angioplastie; NITER, Nephropathy Ischemic ThERapy; RASCAD, Renal Artery Stenosis in Coronary Artery Disease; RR, risk ratio; SNARSCG, Scottish and Newcastle Renal Artery Stenosis Collaborative Group; STAR, STent placement and blood pressure and lipid-lowering for the prevention of progression of renal dysfunction caused by Atherosclerotic ostial stenosis of the Renal artery.
Bavry AA, Kapadia SR, Bhatt DL, Kumbhani DJ. Renal Artery RevascularizationUpdated Meta-analysis With the CORAL Trial. JAMA Intern Med. 2014;174(11):1849-1851. doi:10.1001/jamainternmed.2014.4332
Arguments for renal artery revascularization include blood pressure control, stabilization of renal function, and reduction in adverse cardiovascular events. We previously reported on the randomized clinical trial data to 2009 regarding renal artery revascularization compared with medical therapy.1 That report concluded that renal artery revascularization was associated with marginal improvement in serum creatinine levels (P = .06) and no improvement in systolic blood pressure (P = .32), although there was need for fewer antihypertensive medications (P < .001). Since then, the Cardiovascular Outcomes in Renal Atherosclerotic Lesions (CORAL) Trial has been published.2
Details of the previous meta-analysis have been described.1 Briefly, the MEDLINE database was searched for trials published from study inception through June 2010. We required that patients were randomized to percutaneous revascularization of a renal artery stenosis with or without stenting vs medical therapy alone. Three independent reviewers extracted data elements. Summary relative risks and 95% CIs were calculated for dichotomous variables using a DerSimonian and Laird random-effects model. For continuous variables, the weighted mean difference (WMD) and 95% CIs were computed using a random-effects model. The Begg funnel plot assessed for publication bias, while heterogeneity was assessed by the I2 measure.
An updated search of the MEDLINE database was performed from June 2010 to November 2013, which revealed 2 additional trials.2,3 Data from these trials were extracted (by 2 of us: A.A.B. and D.J.K.) and added to our preexisting database. One minor discrepancy was resolved by discussion. Analyses were performed with STATA statistical software (version 12.0; StataCorp LP).
Overall, there were 8 studies in 2223 patients. The 5 later studies routinely used stents. The mean age ranged from 59 to 72 years, and the proportion of women ranged from 27% to 50%. At baseline, the mean number of antihypertensive medications was 2.43, and the mean systolic blood pressure ranged from 131 to 182 mm Hg. The mean duration of follow-up was 34.2 months.
Renal artery revascularization was not associated with a change in systolic blood pressure from baseline when compared with medical therapy (WMD, 0.12; 95% CI, −0.97 to 1.21; P = .83) but was associated with a reduction in the number of antihypertensive medications required at follow-up (2.96 vs 3.18; WMD, −0.23; 95% CI, −0.33 to −0.12; P < .001). There was no evidence of heterogeneity (I2 = 0) or publication bias (P = .45 for change in systolic blood pressure; P = .85 for medications at follow-up). Revascularization was not associated with a reduction in adverse cardiovascular or renal outcomes compared with medical therapy (Figure). Results were similar when restricted to stent-only trials.
Among patients with renal artery stenosis and hypertension and/or chronic kidney disease, revascularization was of marginal benefit. This therapy slightly reduced the need for antihypertensive medications. However, revascularization did not reduce adverse cardiovascular or renal outcomes compared with medical therapy over a mean follow-up of 34 months.
Patients enrolled in the CORAL Trial likely mirrored clinical practice in that the degree of renal artery stenosis was somewhat modest, and the frequency of bilateral renal artery stenosis was low.2 Also, in the CORAL Trial, the average blood pressure at baseline was 150 mm Hg, a value at which revascularization may be unlikely to provide much benefit. It still remains plausible that revascularization could benefit patients with severe bilateral stenoses, or a critical stenosis that supplies a solitary kidney; however, such a trial is unlikely to be performed. Currently, the only class I recommendation for renal revascularization is in the setting of recurrent pulmonary edema.4
In conclusion, routine revascularization of a renal artery stenosis does not seem to be clinically beneficial.
Corresponding Author: Anthony A. Bavry, MD, MPH, Cardiology Section, Medical Service, North Florida/South Georgia Veterans Health System (Malcolm Randal Veterans Administration Medical Center), 1601 SW Archer Rd, Gainesville, FL 32608 (email@example.com).
Published Online: September 15, 2014. doi:10.1001/jamainternmed.2014.4332.
Author Contributions: Dr Bavry had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Bavry, Kapadia, Kumbhani.
Acquisition, analysis, or interpretation of data: Bhatt, Kumbhani.
Drafting of the manuscript: Bavry, Kapadia, Kumbhani.
Critical revision of the manuscript for important intellectual content: Kapadia, Bhatt, Kumbhani.
Statistical analysis: Bavry.
Study supervision: Bavry, Kapadia.
Conflict of Interest Disclosures: Dr Bavry has received honoraria from the American College of Cardiology and Gilead and research support from Novartis Pharmaceuticals, Gilead, and Eli Lilly. Dr Bhatt has been on the advisory boards for Elsevier Practice Update Cardiology, Medscape Cardiology, and Regado Biosciences; on the board of directors for the Boston VA Research Institute and the Society of Cardiovascular Patient Care; has been chair of American Heart Association Get With The Guidelines Steering Committee; has received honoraria from the American College of Cardiology (editor, Clinical Trials, Cardiosource), Belvoir Publications (editor-in-chief, Harvard Heart Letter), Duke Clinical Research Institute (clinical trial steering committees), Population Health Research Institute (clinical trial steering committee), Slack Publications (chief medical editor, Cardiology Today’s Intervention), WebMD (CME steering committees); has been senior associate editor, Journal of Invasive Cardiology; has been on the data monitoring committees for Duke Clinical Research Institute, Harvard Clinical Research Institute, Mayo Clinic, Population Health Research Institute; has received research grants from Amarin, AstraZeneca, Bristol-Myers Squibb, Eisai, Ethicon, Medtronic (for his role as co–principal investigator of Symplicity HTN-3 and member of the steering committee of Symplicity HTN-4), Sanofi-Aventis, and The Medicines Company; and has performed unfunded research for FlowCo, PLx Pharma, and Takeda. Dr Kumbhani has received honoraria from the American College of Cardiology and Somahlutions Inc. No other disclosures are reported.