A randomized, multi-center, prospective study comparing best medical treatment versus best medical treatment plus renal artery stenting in patients with hemodynamically relevant atherosclerotic renal artery stenosis (RADAR) – one-year results of a pre-maturely terminated study

Abstract

BackgroundThe indications for conservative “best medical treatment” (BMT) versus additional renal artery stenting are a matter of ongoing debate. The RADAR study aimed to evaluate the impact of percutaneous renal artery stenting on the impaired renal function in patients with hemodynamically significant atherosclerotic renal artery stenosis (RAS).MethodsRADAR is an international, prospective, randomized (1:1) controlled study comparing BMT alone versus BMT plus renal artery stenting in patients with duplex sonographic hemodynamically relevant RAS. Follow-up assessments were at 2, 6, and 12 months and at 3 years. The primary endpoint was change in estimated glomerular filtration rate (eGFR) at 12 months.ResultsDue to slow enrollment, RADAR was terminated early after inclusion of 86 of the scheduled 300 patients (28.7%). Change in eGFR between baseline and 12 months was 4.3 ± 15.4 ml/min/1.73 m2 (stent group) and 3.0 ± 14.9 ml/min/1.73 m2 (BMT group), p > 0.999. Clinical event rates were low with a 12-month composite of cardiac death, stroke, myocardial infarction, and hospitalization for congestive heart failure of 2.9% in the stent and 5.3% in the BMT group, p = 0.526, and a 3-year composite of 14.8% and 12.0%, p = 0.982. At 3 years, target vessel (re-)vascularization occurred in one patient (3.0%) in the stent group and in 8 patients (29.4%) in the BMT group.ConclusionIn RADAR, outcomes of renal artery stenting were similar to BMT. These results have to be interpreted with the caveat that the study did not reach its statistically based sample size.Trial registrationClinicaltrials.gov, NCT00640406. Registered on 17 March 2008.Electronic supplementary materialThe online version of this article (doi:10.1186/s13063-017-2126-x) contains supplementary material, which is available to authorized users.

Determinants of long-term outcome in patients after percutaneous stent-assisted intervention on renal artery steno-occlusive atherosclerotic disease

“…[13][14][15][16][17][18][19][20] Among the 8 available RCTs, the CORAL study (Cardiovascular Outcomes in Renal Atherosclerotic Lesions) confirmed the advantage of PTA plus medical therapy over medical therapy alone in terms of improving BP control, while these findings were confirmed only by 2 of the numerous nonrandomized studies. [13][14][15][16][17][18][19][20][21][22] Importantly, BP control with medical therapy does not prevent progression of RAS. Between 36% and 71% of patients were reported to experience progression during 5 years, 23 while renal artery occlusion within 1 year was observed in 16% of medically treated patients.…”

Use of percutaneous transluminal renal angioplasty in atherosclerotic renal artery stenosis: a systematic review and meta-analysis

“…Some other studies 27,45 were unable to detect a clinically significant benefit from PTRA on left ventricular mass in patients with ARAS of 50% to 80%. When stenosis was ≥80% in a recently published RCT, 29 there was improvement in clinical outcomes in cardiac events in 3 years after PTRA. Iwashima et al.…”

“…One record was identified in a search of references. A total of 9 RCTs (EMMA, 23 SNRASCG, 24 DRASTIC, 25 STAR, 26 RASCAD, 27 CORAL, 28 RADAR, 29 NITER, 30 and ASTRAL 31 ) involving 2309 patients were chosen. Figure 1 shows a flowchart illustrating the search strategy for RCTs on PTRA and BMT in patients with ARAS.…”

<p>Severely Impaired Renal Function in Unilateral Atherosclerotic Renal Artery Stenosis Indicated by Renal Slow Perfusion</p>

“…3 The average eGFR of the population was under 60 mL/min in three other clinical studies. 4,14,15 Although RAS leads to renal dysfunction, the exact level of reduced renal perfusion can lead to hemodynamic changes. Visual assessment is widely used in diagnosing vascular diseases, but it is not accurate alone in evaluating the stenotic degree of lesions.…”

“… 3 The average eGFR of the population was under 60 mL/min in three other clinical studies. 4 , 14 , 15 …”