Renal artery revascularization after unsuccessful percutaneous therapy: a single centre experience

Risks and benefits of renal artery stenting in fibromuscular dysplasia: Lessons from the ARCADIA-POL study

INTRODUCTION

Although renal stenting is the standard revascularization method for atherosclerotic renal artery stenosis (RAS) (FMD-RAS), stenting in fibromuscular dysplasia (FMD) RAS is usually limited to periprocedural complications of angioplasty and primary arterial dissection. The main aim of the study was to retrospectively analyze the immediate and long-term results of renal stenting versus angioplasty in patients with FMD.

METHODS

Of 343 patients in the ARCADIA-POL registry, 58 patients underwent percutaneous treatment due to FMD-RAS (in 70 arteries). Percutaneous transluminal renal angioplasty (PTRA) was performed as an initial treatment in 61 arteries (PTRA-group), whereas primary stenting was undertaken in nine arteries (stent-group). Stent-related complications were defined as: in-stent restenosis > 50% (ISR); stent fracture; under-expansion; or migration.

RESULTS

In the PTRA-group, the initial restenosis rate was 50.8%. A second procedure was then performed in 22 arteries: re-PTRA (12 arteries) or stenting (10 arteries). The incidence of recurrent restenosis after re-PTRA was 41.7%. Complications occurred in seven of 10 (70%) arteries secondarily treated by stenting: two with under-expansion and five with ISR. In the stent-group, stent under-expansion occurred in one case (11.1%) and ISR in three of nine stents (33.3%). In combined analysis of stented arteries, either primarily or secondarily, stent-related complications occurred in 11/19 stenting procedures (57.9%): three due to under-expansion and eight due to ISRs. Finally, despite several revascularization attempts, four of 19 (21%) stented arteries were totally occluded and one was significantly stenosed at follow-up imaging.

CONCLUSION

Our study indicates that renal stenting in FMD-RAS may carry a high risk of late complications, including stent occlusion. Further observational data from large-scale registries are required.

Spleno-renal artery transposition in a solitary functioning kidney for treatment-resistant hypertension and acute kidney injury

Renal Artery Stenosis (RAS) is an important cause of treatment-resistant hypertension. Uncontrolled hypertension with RAS can cause progressive chronic kidney disease (CKD) leading to end-stage kidney disease. Therapeutic revascularisation can be helpful in appropriate circumstances where pharmaceutical intervention has failed and significant renovascular disease contributes to resistant hypertension. We present an interesting case of a Caucasian male with peripheral vasculopathy, abdominal aortic aneurysm (AAA), single functioning kidney and ostial RAS caused by stent struts from an endovascular AAA stent graft. He had escalating medications requirement, with repeated failed attempts at percutaneous radiological intervention that led to an episode of contrast-induced acute kidney injury (AKI), before undergoing successful surgical revascularisation by a splenic artery transposition graft to the left renal artery that was performed to improve kidney function and the blood pressure. This report highlights the challenges faced with regard to the management of severe hypertension and progressive CKD.

Endovascular Management of Atherosclerotic Renal Artery Stenosis: Post-Cardiovascular Outcomes in Renal Atherosclerotic Lesions Era Winner or False Alarm?

Renal artery stenosis (RAS) is frequently associated with severe comorbidities such as reduced renal perfusion, hypertension, and end-stage renal failure. In approximately 90% of patients, renal artery atherosclerosis is the main cause for RAS, and it is associated with an increased risk for fatal and non-fatal cardiovascular and renal complications. Endovascular management of atherosclerotic RAS (ARAS) has been recently evaluated by several randomized controlled trials that failed to demonstrate benefit of stenting. Furthermore, the Cardiovascular Outcomes in Renal Atherosclerotic Lesions study did not demonstrate any benefit over the revascularization approach. In this review, we summarized the available data from retrospective, prospective and randomized trials on ARAS to provide clinicians with sufficient data in order to produce useful conclusions for everyday clinical practice.

Combined Microencapsulated Islet Transplantation and Revascularization of Aortorenal Bypass in a Diabetic Nephropathy Rat Model

OBJECTIVE

Revascularization of aortorenal bypass is a preferred technique for renal artery stenosis (RAS) in diabetic nephropathy (DN) patients. Restenosis of graft vessels also should be considered in patients lacking good control of blood glucose. In this study, we explored a combined strategy to prevent the recurrence of RAS in the DN rat model.

METHODS

A model of DN was established by intraperitoneal injection of streptozotocin. Rats were divided into 4 groups: SR group, MIT group, Com group, and the untreated group. The levels of blood glucose and urine protein were measured, and changes in renal pathology were observed. The expression of monocyte chemoattractant protein-1 (MCP-1) in graft vessels was assessed by immunohistochemical staining. Histopathological staining was performed to assess the pathological changes of glomeruli and tubules.

RESULTS

The levels of urine protein and the expression of MCP-1 in graft vessels were decreased after islet transplantation. The injury of glomerular basement membrane and podocytes was significantly ameliorated.

CONCLUSIONS

The combined strategy of revascularization and microencapsulated islet transplantation had multiple protective effects on diabetic nephropathy, including preventing atherosclerosis in the graft vessels and alleviating injury to the glomerular filtration barrier. This combined strategy may be helpful for DN patients with RAS.

[Medicinal or instrumental (corrected) therapy of renal artery stenosis?]

Arteriosclerotic renal artery stenosis (RAS) has an increased incidence in patients with cardiovascular risk factors. Clinically RAS presents in some patients as secondary, sometimes resistant arterial hypertension and in others as chronic renal insufficiency, sometimes with acute renal failure and in a third group both symptoms are observed. Doppler ultrasound plays a central role in the diagnosis of RAS. Therapeutically, it is important to identify hemodynamically relevant RAS before interventional therapy is initiated. The therapy of RAS has been under intensive debate since the publication of randomized controlled trials (RCT) which showed that only a subset of RAS can be successfully treated by interventional therapy. Since then the medicinal therapy of RAS has gained more and more impact. The following questions are raised: which forms of RAS can be treated by which therapy? What is the best medicinal therapy to treat RAS? What substances are recommended?