Renal artery stenosis: prevalence of, risk factors for, and management of in-stent stenosis

Atherosclerotic renovascular disease: a clinical practice document by the European Renal Best Practice (ERBP) board of the European Renal Association (ERA) and the Working Group Hypertension and the Kidney of the European Society of Hypertension (ESH)

Atherosclerotic renovascular disease (ARVD) is the most common type of renal artery stenosis. It represents a common health problem with clinical presentations relevant to many medical specialties and carries a high risk for future cardiovascular and renal events, as well as overall mortality. The available evidence regarding the management of ARVD is conflicting. Randomized controlled trials failed to demonstrate superiority of percutaneous transluminal renal artery angioplasty (PTRA) with or without stenting in addition to standard medical therapy compared with medical therapy alone in lowering blood pressure levels or preventing adverse renal and cardiovascular outcomes in patients with ARVD, but they carried several limitations and met important criticism. Observational studies showed that PTRA is associated with future cardiorenal benefits in patients presenting with high-risk ARVD phenotypes (i.e. flash pulmonary oedema, resistant hypertension or rapid loss of kidney function). This clinical practice document, prepared by experts from the European Renal Best Practice (ERBP) board of the European Renal Association (ERA) and from the Working Group on Hypertension and the Kidney of the European Society of Hypertension (ESH), summarizes current knowledge in epidemiology, pathophysiology and diagnostic assessment of ARVD and presents, following a systematic literature review, key evidence relevant to treatment, with an aim to support clinicians in decision making and everyday management of patients with this condition.

Revascularization for Renovascular Disease: A Scientific Statement From the American Heart Association

Renovascular disease is a major causal factor for secondary hypertension and renal ischemic disease. However, several prospective, randomized trials for atherosclerotic disease failed to demonstrate that renal revascularization is more effective than medical therapy for most patients. These results have greatly reduced the generalized diagnostic workup and use of renal revascularization. Most guidelines and review articles emphasize the limited average improvement and fail to identify those clinical populations that do benefit from revascularization. On the basis of the clinical experience of hypertension centers, specialists have continued selective revascularization, albeit without a summary statement by a major, multidisciplinary, national organization that identifies specific populations that may benefit. In this scientific statement for health care professionals and the public-at-large, we review the strengths and weaknesses of randomized trials in revascularization and highlight (1) when referral for consideration of diagnostic workup and therapy may be warranted, (2) the evidence/rationale for these selective scenarios, (3) interventional and surgical techniques for effective revascularization, and (4) areas of research with unmet need.

How should we define appropriate patients for percutaneous transluminal renal angioplasty treatment?

Renovascular hypertension (RVH) is one of the most common causes of secondary hypertension and can result in resistant hypertension. RVH is associated with an increased risk for progressive decline in renal function, cardiac destabilization syndromes including "flash" pulmonary edema, recurrent congestive heart failure, and cerebrocardiovascular disease. The most common cause of renal artery stenosis (RAS) is atherosclerotic lesions, followed by fibromuscular dysplasia. The endovascular technique of percutaneous transluminal renal angioplasty (PTRA) with or without stenting is one of the standard treatments for RAS. Randomized controlled trials comparing medical therapy with PTRA to medical therapy alone have failed to show a benefit of PTRA; however, the subjects of these randomized clinical trials were limited to atherosclerotic RAS patients, and patients with the most severe RAS, who would be more likely to benefit from PTRA, might not have been enrolled in these trials. This review compares international guidelines related to PTRA, reevaluates the effects of PTRA treatment on blood pressure and renal and cardiac function, discusses strategies for the management of RVH patients, and identifies factors that may predict which patients are most likely to benefit from PTRA.

Long-term outcomes and determinants of stenosis recurrence after renal artery angioplasty in hypertensive patients with renovascular disease

INTRODUCTION

Restenosis (RS) following percutaneous angioplasty (PTA) of renal artery stenosis (RAS) might have an unfavourable impact on renal function and blood pressure (BP) outcomes.

AIM

To evaluate the prevalence and predictors of RS in patients treated with PTA for RAS, and the relationship between BP and renal function (RF) changes with RS.

MATERIAL AND METHODS

We analysed freedom from RS in 210 patients (age 64.6 ±12.8 years; range: 20-85), who underwent 248 successful stent-assisted PTAs in RAS. The change in levels of serum creatinine (SCC), estimated glomerular filtration rate (eGFR), systolic/diastolic BPs (SBP/DBP) were analysed prior to PTA, at 6-, 12-month, and final follow-up visits, and whenever RS was diagnosed.

RESULTS

RS was identified in 30 (14.3%) patients, and there were 36 (14.5%) lesions. The Kaplan-Meier RS-free survival curves in fibromuscular dysplasia, atherosclerosis, and vasculitis at 1 and 7 years were: 100% and 100%; 95.6 and 83.9%; and 71.4 and 39.7%, respectively. Patients with RS, as compared to RS-free patients, presented with less pronounced changes in respect with: SBP (1.4 ±17.6 vs. -15.8 ±25.8 mm Hg; p = 0.01), DBP (2.64 ±10.1 vs. -6.5 ±14.1 mm Hg; p = 0.002), SCC (22.4 ±55.2 vs. -3.6 ±43.9 µmol/l; p = 0.002), and eGFR (-1.85 ±18 vs. -5.34 ±19.5 mm Hg; p = 0.045). In multivariate Cox regression analysis, independent predictors of RS occurred: lack of BP decrease (HR = 4.19, 95% CI: 1.67-10.3; p = 0.002), eGFR increase < 0.17 ml/min/1.73 m2 (HR = 2.93, 95% CI: 1.08-7.91; p = 0.033), stent diameter ≤ 5 mm (HR = 2.76, 95% CI: 1.09-6.97; p = 0.031), and vasculitis (HR = 5.61, 95% CI: 1.83-17.2; p = 0.003). RS was treated in 24 patients with RS recurrence in 20%.

CONCLUSIONS

The RS rate differs depending on RAS aetiology. Lack of SBP/DBP and eGFR improvement, vasculitis, and stent diameter are associated with RS risk. Repeated PTA is effective, but recurrent RS occurs in 20% of cases.

Follow-up of patients after revascularisation for peripheral arterial diseases: a consensus document from the European Society of Cardiology Working Group on Aorta and Peripheral Vascular Diseases and the European Society for Vascular Surgery

Peripheral arterial diseases comprise different clinical presentations, from cerebrovascular disease down to lower extremity artery disease, from subclinical to disabling symptoms and events. According to clinical presentation, the patient's general condition, anatomical location and extension of lesions, revascularisation may be needed in addition to best medical treatment. The 2017 European Society of Cardiology guidelines in collaboration with the European Society for Vascular Surgery have addressed the indications for revascularisation. While most cases are amenable to either endovascular or surgical revascularisation, maintaining long-term patency is often challenging. Early and late procedural complications, but also local and remote recurrences frequently lead to revascularisation failure. The rationale for surveillance is to propose the accurate implementation of preventive strategies to avoid other cardiovascular events and disease progression and avoid recurrence of symptoms and the need for redo revascularisation. Combined with vascular history and physical examination, duplex ultrasound scanning is the pivotal imaging technique for identifying revascularisation failures. Other non-invasive examinations (ankle and toe brachial index, computed tomography scan, magnetic resonance imaging) at regular intervals can optimise surveillance in specific settings. Currently, optimal revascularisation surveillance programmes are not well defined and systematic reviews addressing long-term results after revascularisation are lacking. We have systematically reviewed the literature addressing follow-up after revascularisation and we propose this consensus document as a complement to the recent guidelines for optimal surveillance of revascularised patients beyond the perioperative period.

Resistant Hypertension: Detection, Evaluation, and Management: A Scientific Statement From the American Heart Association

Resistant hypertension (RH) is defined as above-goal elevated blood pressure (BP) in a patient despite the concurrent use of 3 antihypertensive drug classes, commonly including a long-acting calcium channel blocker, a blocker of the renin-angiotensin system (angiotensin-converting enzyme inhibitor or angiotensin receptor blocker), and a diuretic. The antihypertensive drugs should be administered at maximum or maximally tolerated daily doses. RH also includes patients whose BP achieves target values on ≥4 antihypertensive medications. The diagnosis of RH requires assurance of antihypertensive medication adherence and exclusion of the "white-coat effect" (office BP above goal but out-of-office BP at or below target). The importance of RH is underscored by the associated risk of adverse outcomes compared with non-RH. This article is an updated American Heart Association scientific statement on the detection, evaluation, and management of RH. Once antihypertensive medication adherence is confirmed and out-of-office BP recordings exclude a white-coat effect, evaluation includes identification of contributing lifestyle issues, detection of drugs interfering with antihypertensive medication effectiveness, screening for secondary hypertension, and assessment of target organ damage. Management of RH includes maximization of lifestyle interventions, use of long-acting thiazide-like diuretics (chlorthalidone or indapamide), addition of a mineralocorticoid receptor antagonist (spironolactone or eplerenone), and, if BP remains elevated, stepwise addition of antihypertensive drugs with complementary mechanisms of action to lower BP. If BP remains uncontrolled, referral to a hypertension specialist is advised.

Predictive Value of Duplex Ultrasound for Significant In-Stent Restenosis after Percutaneous Transluminal Renal Artery Stent Placement: A Propensity Score Matching Analysis

To evaluate the value of pre-stenting and early post-stenting (<1 mo) duplex ultrasound parameters in predicting significant in-stent restenosis (ISR), we matched significant ISR patients 1:1 with controls without ISR in pre-stenting and early post-stenting (<1 mo) periods, respectively, using propensity score matching. Duplex ultrasound parameters, such as renal length difference between non-lesion side and lesion side within patient, trans-lesion peak systolic velocity and renal aortic ratio, were compared between cases and controls, and the area under the receiver operating characteristic curve (AUROC) was charted to predict ISR. After propensity score matching, 28 cases were matched in the pre-stenting period and 16 cases in the early post-stenting time period. Pre-stenting renal length difference, early post-stenting peak systolic velocity and renal aortic ratio showed significant differences in case-control comparisons. Early post-stenting peak systolic velocity (AUROC: 0.826, cutoff: 141 cm/s) and renal aortic ratio (AUROC: 0.770, cutoff: 1.75) performed well in predicting significant ISR and may serve as non-invasive markers in ISR surveillance.

Tratamento da recidiva de reestenose intra-stent renal por angioplastia com balão farmacológico

Nos últimos anos, balões farmacológicos surgiram como promissora alternativa terapêutica em intervenções endovasculares. Com essa tecnologia, transferem-se drogas antiproliferativas à parede arterial, sem a necessidade de implante metálico para liberação. Descreve-se o caso de um paciente com uma segunda recidiva de reestenose intra-stent renal tratada por angioplastia com balão coberto por droga, com boa evolução clínica caracterizada por adequado controle pressórico e redução de classes e dosagem dos anti-hipertensivos. Os resultados obtidos com balões farmacológicos em outros territórios e esta experiência isolada podem contribuir como sugestão para o uso desses dispositivos na reestenose intra-stent renal, com resultados iniciais satisfatórios.

Current Concepts in the Treatment of Renovascular Hypertension

Renovascular disease (RVD) remains a major cause of secondary and treatment-resistant hypertension. Most cases are related either to fibromuscular or atherosclerotic lesions, but a variety of other causes including arterial dissection, stent occlusion, and embolic disease can produce the same syndrome. Recent studies emphasize the kidney's tolerance to moderate flow reduction during antihypertensive drug therapy and the relative safety of medical therapy to control blood pressure. Several prospective trials in moderate RVD fail to identify major benefits from endovascular revascularization for moderate atherosclerotic disease. However, high-risk and progressive renovascular syndromes are recognized to be relatively refractory to medical therapy only and respond better to combining renal revascularization with ongoing medical therapy. Clinicians caring for complex hypertension should be familiar with pathogenic pathways, imaging techniques, and a rational approach to managing renovascular hypertension in the current era.

A Novel Technique of Stenting of the Renal Artery In-Stent Restenosis with GuideLiner® through Radial Approach

In-stent restenosis of the renal arteries is relatively common and its management is not well studied. An 83-year-old female with bilateral renal artery stenosis and balloon angioplasty and stenting bilaterally one year ago was found to have recurrent severe elevations in the blood pressure despite medical management. Renal artery duplex showed 60–99% stenosis of the right renal artery and 20–59% stenosis of the left renal artery. A subsequent angiography of the right renal artery revealed 80% in-stent restenosis at the ostium. We describe a new approach of balloon angioplasty and stenting through radial access site with the assistance of a GuideLiner in a complex in-stent restenosis of the renal artery.

Renal Arterial Disease and Hypertension

Renal artery disease produces a spectrum of progressive clinical manifestations ranging from minor degrees of hypertension to circulatory congestion and kidney failure. Moderate reductions in renal blood flow do not induce tissue hypoxia or damage, making medical therapy for renovascular hypertension feasible. Several prospective trials indicate that optimized medical therapy using agents that block the renin-angiotensin system should be the initial management. Evidence of progressive disease and/or treatment failure should allow recognition of high-risk subsets that benefit from renal revascularization. Severe reductions in kidney blood flow ultimately activate inflammatory pathways that do not reverse with restoring blood flow alone.

Effects of Percutaneous Transluminal Renal Angioplasty on Office and Home Blood Pressure and Home Blood Pressure Variability in Hypertensive Patients With Renal Artery Stenosis

This study included 126 hypertensive patients with renal artery stenosis (mean age, 63 years; 22.2% fibromuscular dysplasia [FMD]) and investigated the effects of percutaneous transluminal renal angioplasty on office and home blood pressure (BP), and BP variability estimates derived from home BP, both at baseline and up to 12 months after angioplasty. Home BP was measured for 7 consecutive days, and the threshold defining uncontrolled home BP was ≥135/85 mm Hg. In both the FMD and atherosclerotic stenosis (ARAS) groups, office and home BP decreased significantly after angioplasty (all P <0.01), but the decrease in morning home (−22±19 versus −10±20 mm Hg; P <0.01) but not in office (−32±24 versus −23±28 mm Hg; P =0.11) systolic BP at 12 months was significantly greater in FMD. In both groups, all morning BP variability indices except the coefficient of variation in ARAS decreased significantly after revascularization (all P <0.05 by repeated-measures ANOVA). The decrease in all morning systolic BP variability estimates was greater for FMD than for ARAS (all P <0.05 by 2-way repeated-measures ANOVA), with the exception of variability independent of the mean ( P =0.11). The prevalence of uncontrolled home BP was 77.0% at baseline and 38.9% after revascularization. Duration of hypertension (odds ratio, 1.48), ARAS (odds ratio, 3.18), and the presence of proteinuria (odds ratio, 2.10) were independent predictors of uncontrolled home BP after revascularization (all P <0.05). In conclusion, renal angioplasty produced a greater decrease of morning home systolic BP in FMD; however, in both groups, it decreased BP variability irrespective of BP response. Measurement of home BP seems to be important for treatment success, especially in ARAS.

Treatment of In-Stent Restenosis in Patients with Renal Artery Stenosis

PURPOSE

To determine clinical outcomes of patients treated for renal artery in-stent restenosis (ISR) with atherosclerotic renal artery stenosis.

MATERIALS AND METHODS

A retrospective review was performed of the clinical data of all patients who underwent renal artery stent placement for atherosclerotic renal artery stenosis from 1996 to 2009. Medical records of patients were reviewed for relevant clinical history, including blood pressure, antihypertensive medications, and renal function data before and after an intervention. In 1,052 patients, 1,090 renal artery stent placements were performed. Of these, 101 stents in 79 patients developed ISR, which was treated with either percutaneous transluminal angioplasty (PTA) or repeat stent placement. Procedural details, including modality of intervention, stent diameter, and time to restenosis, were recorded. Hypertensive agent and use of statins were recorded. Univariate analysis was performed to identify risk factors associated with restenosis after treatment of ISR.

RESULTS

Patients treated with repeat stent placement were 6.89 times more likely to lose patency after treatment than patients treated with PTA (P < .01). No additional clinical or procedural factor, including smoking history; presence of cardiac, renal, or metabolic disease; use of statin at time of ISR treatment; or diameter of treatment (stent or PTA), had a significant association with duration of stent or angioplasty patency.

CONCLUSIONS

Treatment of renal artery ISR with PTA among patients with atherosclerotic renal artery stenosis has a lower rate of subsequent ISR compared with repeat stent placement.

Renal artery stenosis and mean platelet volume

Objective:

Increased mean platelet volume (MPV) has been reported in various atherosclerotic diseases. The aim of our study was to investigate the relationship between the atherosclerotic renal artery stenosis (ARAS) and various hematological parameters including MPV.

Methods:

This study was performed with a retrospective review of the angiographic images of patients who underwent renal angiography at Bülent Ecevit University catheter laboratory between January 2004 and December 2009. The patients were trichotomized into three groups based on the presence and severity of renal artery stenosis (RAS). Group 1 included patients with a critical RAS (33 patients; 18 female (F), 15 male (M); mean age 61.6±11.5 years), group 2 consisted of patients with non-critical RAS (26 patients; 15 F, 11 M; mean age 58.1±11.3 years), and group 3 was composed of patients without RAS (69 patients; 38 F, 31 M; mean age 53.5±11.9 years). Demographic data, complete blood count, and biochemical parameters were compared between the groups.

Results:

Comparison of the hematological parameters revealed that MPV and platelet distribution width were significantly higher in group 1 than in group 2 and 3 (8.96±0.99 fL versus 8.35±0.76 fL, 8.31±0.79 fL, respectively; p=0.001; 16.53±0.58% versus 16.19±0.56%, 16.29±0.53%, respectively; p=0.04).

Conclusion:

MPV levels are higher in patients with ARAS. Considering both the effect of platelets on atherosclerosis and their close association with other risk factors, MPV level may be an important factor in pathogenesis of ARAS.