A Rare Case of Focal Renal Fibromuscular Dysplasia Treated With Angioplasty: A Case Report.

BACKGROUND: Fibromuscular dysplasia is an idiopathic, segmental, nonatherosclerotic, noninflammatory vascular disease that can lead to arterial stenosis, tortuosity, occlusion, aneurysms, and dissection. Fibromuscular dysplasia is a rare cause of hypertension that can easily be missed. To date, there has been no definitive treatment for fibromuscular dysplasia. CASE REPORT: In this report, we present an uncommon case of renovascular hypertension in a 21-year-old non-white female with a 3-year history of hypertension secondary to fibromuscular dysplasia involving bilateral renal arteries. Computed tomography angiography during the arterial phase revealed distal focal narrowing of the right main renal artery, distal focal narrowing of the left main renal artery, and proximal focal narrowing of the left accessory lower renal artery. Percutaneous balloon dilatation of the stenotic lesion was performed successfully up to 1 year After the procedure, the arterial blood pressure was within the normal range (110/70 to 125/75 mmHg) without medication. After 1 year of follow-up, CTA revealed re-stenosis in left main renal artery without clinical symptoms and normal blood pressure. Repeated procedure was done successfully. CONCLUSIONS: This case report highlights the difficulty in the diagnosis and treatment of focal fibromuscular dysplasia in young non-white female patients. Computerized tomographic angiography is a useful tool for identifying the cause and showing the benefit of percutaneous transluminal renal angioplasty treatment for this rare entity, as an early percutaneous angioplasty intervention may have a clinical cure for hypertension.

Obesity blunts amelioration of cardiac hypertrophy and fibrosis by human mesenchymal stem/stromal cell-derived extracellular vesicles.

Renovascular hypertension (RVH) can induce cardiac damage that is reversible using adipose tissue-derived mesenchymal stromal/stem cells (A-MSCs). However, A-MSCs isolated from patients with obesity are less effective than lean-A-MSC in blunting hypertensive cardiomyopathy in mice with RVH. We tested the hypothesis that this impairment extends to their obese A-MSC-extracellular vesicles (EVs) progeny. MSCs were harvested from the subcutaneous fat of obese and lean human subjects, and their EVs were collected and injected into the aorta of mice 2 wk after renal artery stenosis or sham surgery. Cardiac left ventricular (LV) function was studied with MRI 2 wk later, and myocardial tissue ex vivo. Blood pressure, LV myocardial wall thickness, mass, and fibrosis that were elevated in RVH mice were suppressed only by lean EVs. Hence, human A-MSC-derived lean EVs are more effective than obese EVs in blunting hypertensive cardiac injury in RVH mice. These observations highlight impaired paracrine repair potency of endogenous MSCs in patients with obesity.NEW & NOTEWORTHY Injection of A-MSC-derived EVs harvested from patients who are lean can resolve myocardial injury in mice with experimental renovascular hypertension more effectively than A-MSC-derived EVs from patients with obesity. These observations underscore and might have important ramifications for the self-healing capacity of patients with obesity and for the use of autologous EVs as a regenerative tool.

Renovascular Hypertension with Progressive Atherosclerotic Renal Artery Stenosis in an Elderly Patient with Known Fibromuscular Dysplasia: A Case Report.

BACKGROUND Atherosclerotic renal artery stenosis (ARAS) and renovascular fibromuscular dysplasia (FMD) are 2 of the most common etiologies of renovascular hypertension. They have different pathophysiologies, risk factors, presentations, and treatment options. However, as our population ages, it can become increasingly common to see patients who previously had FMD who develop ARAS at an advanced age, indicated by recurrent renovascular hypertension. CASE REPORT We present a case of a 66-year-old female patient who, in 2007, had presented with uncontrolled hypertension. She underwent magnetic resonance angiography and was found to have bilateral FMD, for which she received balloon angioplasty to a severe lesion on the mid-right renal artery and subsequently had normalization of blood pressures and resolution of symptoms. In 2021 she returned with uncontrolled hypertension while being treated with 3 antihypertensives. Bilateral renal arteriography revealed new severe ostial stenosis of the left renal artery and a patent right renal artery in which balloon angioplasty was performed 14 years ago. Based on the angiographic pattern of this new left RAS, we concluded this lesion was caused by atherosclerosis. The left ostial lesion was treated with a bare-metal stent and the patient was continued on antihypertensive medication and statin; at follow-up 4 months later, her blood pressures had normalized. CONCLUSIONS This case features a patient who developed severe ARAS with underlying history of bilateral renal artery FMD. Clinicians need to be aware that in patients with FMD, worsening renovascular hypertension at an advanced age could indicate the development of new hemodynamically significant ARAS. These patients need repeat diagnostic testing and treatment with medial optimization with or without endovascular revascularization in the appropriate clinical setting.

Effects of mesenchymal stem cells in renovascular disease of preclinical and clinical studies: a systematic review and meta-analysis.

Renal artery stenosis (RAS) causes severe renovascular hypertension, worsening kidney function, and increased cardiovascular morbidity. According to recent studies, mesenchymal stem cells (MSCs) administration is a promising therapy for the improvement of RAS outcomes. The meta-analysis aims to evaluate the therapeutic effects of MSC therapy on RAS. We performed a search in MEDLINE, Web of Science, Embase, and Cochrane Library from inception to 5, October 2022. We included 16 preclinical and 3 clinical studies in this meta-analysis. In preclinical studies, the pooled results indicated that animals treated with MSCs had lower levels of systolic blood pressure (SBP) (SMD = - 1.019, 95% CI - 1.434 to - 0.604, I2 = 37.2%, P = 0.000), serum creatinine (Scr) (SMD = - 1.112, 95% CI - 1.932 to - 0.293, I2 = 72.0%, P = 0.008), and plasma renin activity (PRA) (SMD = - 0.477, 95% CI - 0.913 to 0.042, I2 = 43.4%, P = 0.032). The studies also revealed increased levels of renal blood flow (RBF) in stenotic kidney (STK) (SMD = 0.774, 95% CI - 0.351 to 1.197, I2 = 0%, P = 0.000) and the glomerular filtration rate (GFR) of STK (SMD = 1.825, 95% CI 0.963 to 2.688, I2 = 72.6%, P = 0.000). In clinical studies, the cortical perfusion and fractional hypoxia of the contralateral kidney (CLK) were alleviated by MSC therapy. Taken together, this meta-analysis revealed that MSCs therapy might be a promising treatment for RAS. However, due to the discrepancy between preclinical studies and early clinical trials outcomes, MSC therapy couldn't be recommended in clinical care for the moment, more high-quality randomized controlled clinical trials are needed to validate our conclusions and standardize MSCs protocols.

Malignant arterial hypertension in a 2-month-old girl: Etiological diagnosis and treatment.

A 2-month-old girl presented with malignant arterial hypertension revealing bilateral renal artery stenosis secondary to neurofibromatosis type 1 (NF1). Life-supporting care was initiated immediately. High-dose peripheral vasodilator therapy induced life-threatening toxicity; vascular surgery was therefore performed. Technical difficulties due to the young age and low body weight of the patient resulted in fatal bleeding. Renovascular disease is an important cause of pediatric hypertension. NF1-associated renovascular hypertension in young pediatric patients is rare, and its highly specialized management is best delivered via a multidisciplinary approach. The long-term prognosis remains poor.

Percutaneous cutting balloon angioplasty for the treatment of renovascular hypertension in children and adolescents.

OBJECTIVE: Percutaneous transluminal renal angioplasty (PTRA), the recommended treatment in children with renovascular hypertension (RVH), often has unsatisfactory outcomes. Cutting balloons may improve the results of angioplasty in different vascular beds with complex and resistant lesions. We retrospectively analysed the effects of percutaneous cutting balloon angioplasty (PCBA) on blood pressure, cardiac mass and renal artery acceleration time in children/adolescents referred to our centre for RVH. PATIENTS AND METHODS: Thirteen patients (aged 9-19 years) with renal artery stenosis (RAS) and severe hypertension were identified. RASs were focal fibromuscular (FMD) or FMD-like dysplasia (in six cases bilateral, in five associated with mid aortic syndrome). Ten patients had uncontrolled hypertension, in nine cases associated with left ventricular hypertrophy (LVH). Acceleration time was abnormal in all stenotic arteries. Eighteen PCBA were performed, in three arteries associated with stent implantation. RESULTS: PCBA was technically successful in all individuals without major complications. In one patient, an intra-stent restenosis occurred, successfully redilated with conventional angioplasty without recurrence at 4 years distance. One year after PCBA, mean SBP and DBPs were markedly reduced from 146 ±â€Š25 to 121 ±â€Š10 mmHg and from 87 ±â€Š11 to 65 ±â€Š12 mmHg, respectively ( P  < 0.001 for both). At that time, hypertension was cured in seven children and controlled in five individuals. This favourable outcome was confirmed with ambulatory blood pressure measurement in four patients. At the latest follow-up, left ventricular mass and acceleration time were normal in all patients. CONCLUSION: PCBA proved to be a well tolerated and effective procedure that can be considered as an alternative to PTRA to treat hypertensive children/adolescents with recurrent or resistant RAS.

Presentation, treatment, and outcome of renovascular hypertension below 2 years of age.

Renovascular hypertension in most cases requires endovascular treatment and/or surgery. This is technically much more difficult in small children and there is very limited published knowledge in this age group. We here present treatment and outcome of young children with renovascular hypertension at our institution. Children below 2 years of age, with renovascular hypertension between January 1998 and March 2020 were retrospectively reviewed. Demographics and treatment modalities were noted. Primary outcome was blood pressure within a week after the procedures and at last available visit. Sixty-six angiographies were performed in 34 patients. Median age at time of first angiography was 1.03 (interquartile range (IQR) 0.4-1.4) years and systolic blood pressure at presentation 130 (IQR 130-150) mm Hg. Thirty-eight percent (13/34) of children were incidentally diagnosed and 18% (6/34) presented with heart failure. Twenty-six (76%) children had main renal artery stenosis and 17 (50%) mid-aortic syndrome. Seventeen (50%) children showed intrarenal, six (18%) mesenteric, and three (9%) cerebrovascular involvement. Twenty patients underwent 45 percutaneous transluminal angioplasty procedures and seven children surgeries. In 44% of the 16 patients who underwent only percutaneous transluminal angioplasty blood pressure was normalized, 38% had improvement on same or decreased treatment and 19% showed no improvement. Complications were seen in 7.5% (5/66) of angiographies. In four of the seven (57%) children who underwent surgery blood pressure was normalized, two had improved (29%) and one unchanged (14%) blood pressure. CONCLUSION: In small children with renovascular hypertension below the age of 2 years, percutaneous transluminal angioplasty caused significant improvement in blood pressure with low complication profile. Surgery can be recommended where percutaneous transluminal angioplasty and medical treatments failed. WHAT IS KNOWN: • Renovascular hypertension is diagnosed in all age groups from a few weeks of life until adulthood. • Both angioplasty and surgery are significantly more difficult to perform in small children and the published information on short and long-term outcome in these children is very scarce. WHAT IS NEW: • Children below the age of two years can safely and successfully undergo selective renal angiography and also safely be treated with angioplasty. • We here present a large group of babies and infants where angioplasty and in some cases surgery effectively and safely improved their blood pressure.

Renal artery revascularization is a controversial treatment strategy for renal artery stenosis: A case series and a brief review of the current literature.

Renal artery stenosis (RAS) may cause secondary hypertension, progressive decline in renal function, and cardiac destabilization syndromes including "flash" pulmonary edema, recurrent congestive heart failure, and cerebro-cardiovascular disease. Atherosclerotic lesions, fibromuscular dysplasia, and vasculitides are the pathophysiological basis of the disease. Common therapeutic pathways for RAS include medical therapy and revascularization with or without stenting. Randomized controlled trials evaluating renal revascularization have not reported any advantages of revascularization over medical therapy alone in terms of renal function improvement or prevention of cardiovascular events. However, mounting clinical experience suggests that the best strategy in RAS management is to identify which patients are most likely to benefit from renal artery stenting and to optimize the safety and durability of the procedure. This review presents 3 cases of patients who have undergone renal revascularization and discusses the available clinical evidence for the identification of RAS patients who will potentially respond well to revascularization.

Outcomes Following the Endovascular Treatment of Renal Artery Stenosis Caused by Fibromuscular Dysplasia: A Systematic Review and Meta-Analysis.

OBJECTIVE: Renal artery revascularization has been performed to improve blood pressure control and to cure hypertension in patients with renal artery fibromuscular dysplasia (RAFMD). We herein conducted a systematic review and meta-analysis of studies assessing outcomes associated with the treatment of hypertensive RAFMD patients via endovascular angioplasty in order to offer an up-to-date overview of the relative costs and benefits of this approach to revascularization in RAFMD patients. METHODS: We systematically searched the PubMed and Embase databases and the Cochrane Central Register for Controlled Trials to identify relevant studies published as of January 15, 2020. Key outcomes of interest in these studies included technical success, the incidence of perioperative complications, cure rates, and overall improvement rates. RESULTS: In total, we identified 36 relevant studies of 1916 total repairs conducted in 1191 patients. Of these included studies, 33 were retrospective, while 3 were prospective. The overall technical success rate across these studies was 94.3%. Rates of total, major, and minor complications in these pooled studies were 12.9%, 4.6%, and 7.4%, respectively. Pooled rates of cured hypertension and improved hypertension following angioplasty, defined according to study-specific criteria, were 37.0% [95% CI: 27.0%-47.0%] and 80.0% [95% CI: 75.0% to 84.0%], respectively, although these rates varied highly among studies. Cure rates for studies used current clinical definitions for substantial variations across studies. Cure rates in studies using current definitions of cured hypertension (blood pressure <140/90 mm Hg without treatment) were just 18.1% following angioplasty. Cure rates fell markedly with increasing mean patient age (OR associated with an increase in mean age of 10 years: -0.24 [95% CI: -0.44 to -0.04, P = 0.019] and with mean known duration of hypertension (OR associated with an increase in mean hypertension duration of 5 years: -0.09 [95% CI: -0.12 to -0.05, P = 0.001]). CONCLUSIONS: These findings suggest that endovascular treatment yielded moderate benefits to RAFMD patients, with substantial variation across studies. The blood pressure outcome was strongly influenced by patient age.

Insights from intravascular pressure measurement of renal artery revascularization in patients with fibromuscular dysplasia: The DYSART study.

OBJECTIVE: The indication of percutaneous renal transluminal angioplasty (PTRA) in fibromuscular dysplasia (FMD) is mainly based on renal artery stenosis (RAS) due to atherosclerosis criteria, which are not specific to FMD. Consequently, the selection of patients who could benefit from this treatment and its effectiveness remain uncertain. The aims of this study were to: (1) report the effects of PTRA guided by trans-stenotic pressure measurements on hypertension 7 months after treatment; (2) assess the impact of pressure measurement to guide treatment efficacy in comparison to visual angiographic parameters; and (3) evaluate the reproducibility and accuracy of the stenosis measurement using a 4F catheter in comparison to a pressure guidewire. METHODS: This prospective multi-centric study analyzed 24 patients with hypertension with RAS due to FMD that required PTRA. Clinical, duplex ultrasound, and angiographic indices were collected, and patients were followed up for 7 months (±1 month). Angiographic indices were measured twice both by a pressure guidewire and a 4F catheter. Assessment of procedural and clinical success of angioplasty was performed for all patients. RESULTS: Twenty-three patients (96%) had procedural success (considered as a post-PTRA translesional systolic gradient ≤10 mmHg or reduced by at least 80%) with a significant decrease in the systolic gradient after angioplasty (26.50 mmHg; [interquartile range, 16.75-38.75] vs 0.00 [interquartile range, 0.00-2.00]; P < .01). Three patients (12%) had complications, including two renal artery dissections and one partial renal infarction. Twenty-one patients (88%) were clinical responders to angioplasty at follow-up. Visual stenosis assessment showed a poor correlation with systolic gradient measurement before and after PTRA (R from -0.05 to 0.41; P = 0.06-0.82). High correlations were found between pressure measurements made by a 4F catheter and guidewire (R from 0.64 to 0.89; P ≤ .003). CONCLUSIONS: In patients selected by clinical indicators and duplex ultrasound, reaching a translesional systolic gradient ≤10 mmHg or reduced by at least 80% after angioplasty, promotes a high success rate for PTRA in hypertension due to FMD RAS.

Endovascular interventions in main renal artery pathologies: an overview and update.

Renal arteries are involved in a wide spectrum of pathologies including atherosclerosis, fibromuscular dysplasia, Takayasu arteritis, aneurysms, and aortic type B dissections extending into main renal arteries. They manifest as renovascular hypertension, renal ischemia, and cardiovascular dysfunction. The location of the renal arteries in relation to the abdominal aortic aneurysm is a critical determinant of interventional options and long-term prognosis. This article provides a comprehensive review of the role of interventional radiologists in transcatheter interventions in various pathologies involving the main renal arteries with analysis of epidemiology, pathophysiology, newer interventional techniques, and management options.

Retrograde Recanalization for Proximal Occlusion of the Right Renal Artery through a Compensated Collateral Artery in a 10-year-old Patient.

BACKGROUND: To describe a retrograde recanalization for the proximal occluded lesion in right renal artery (RRA) in young patient with fibromuscular dysplasia (FMD). METHODS: A 10-year-old girl presented to our hospital with proximal RRA occlusion and refractory hypertension though she took anti-hypertension medicines. Her renin and aldosterone were beyond the normal level in both base state and excited state. Her glomerular filtration rate at right kidney was only 18.4 ml/min. Angiography revealed proximal RRA occlusion and a compensated collateral artery (CCA) from the infrarenal aorta to the RRA. She was thus diagnosed with focal FMD. A retrograde recanalization was performed through this CCA. RESULTS: Angioplasty and stenting were successfully performed to treat the proximal RRA occlusion. Postoperatively, the glomerular filtration rate in the right kidney improved. One-year follow-up revealed that, the blood pressure maintained at normal range without any antihypertensive agents. No other discomfort was complained. CONCLUSIONS: It is feasible to establish a working pathway with patient's compensated collateral artery to treat the renal artery occlusion.

Midaortic syndrome and renovascular hypertension.

Midaortic syndrome (MAS) is a rare condition characterized by stenosis of the abdominal aorta with or without the involvement of branch vessels. The majority of cases are thought to be idiopathic though MAS has been associated with a number of conditions including granulomatous vasculitis, neurofibromatosis-1 (NF-1), Alagille Syndrome, fibromuscular dysplasia (FMD), and Williams syndrome. Patients typically present with hypertension due to decreased renal perfusion. Less common presentations include renal insufficiency, heart failure, claudication, stroke, and abdominal pain. Imaging modalities help establish the diagnosis of MAS including duplex ultrasound, computed tomography angiography (CTA), magnetic resonance angiography (MRA), and angiography. Initial therapy focuses on medical management with antihypertensives prior to intervention. Invasive interventions are indicated when there is evidence of end organ damage or dysfunction such as decreased renal function, poorly growing kidneys, cerebrovascular accident, left ventricular hypertrophy or frank cardiac failure. Endovascular interventions may assist in diagnosis and may treat some lesions although reintervention rates are high. Most patients require some type of surgical intervention, and a variety of surgical options are available based on anatomic findings. Renal revascularization may be accomplished by renal artery bypass, autotransplantation, or renal artery reconstruction. Aortic lesions may be repaired using patch angioplasty or aortoaortic bypass. Mesenteric arteries do not typically require reconstruction as they are rarely symptomatic. More novel options include the use of tissue expanders to lengthen the aorta to allow for primary aortic reconstruction (TESLA) or the use of the meandering mesenteric artery as an autologous aortic bypass graft (MAGIC).

Timing of procedural interventions in childhood renovascular hypertension.

BACKGROUND: Renovascular hypertension (RVHTN) is a rare, often complex condition due to multiple etiologies including congenital stenoses, vasculitides, and fibromuscular dysplasia. Among children with RVHTN who require multiple and escalating medications to control blood pressure, the optimal timing of a procedural intervention involves a balance of numerous factors. CASE-DIAGNOSIS/TREATMENT: In this presentation of a 1-month-old girl with RVHTN, the treating medical team had to consider multiple factors in the initial management and timing of interventions to treat her underlying cause of RVHTN, including concerns for kidney health, degree of hypertension, age and size of the patient, and potential methods of procedural intervention. Initially, she was treated conservatively until concern for poor renal growth arose and a durable surgical intervention was thought feasible and safe. CONCLUSION: The evidence regarding the timing of non-medical interventions in pediatric RVHTN is limited. Considerations should include patient age, size, disease severity, comorbid conditions, and degree of medical management required to maintain safe blood pressures that allow for growth and reverse cardiac damage. The optimal interventions have not been evaluated by controlled trials and should be decided on a case-by-case basis with consideration of center expertise and family preferences.

Renovascular hypertension in pediatric patients: update on diagnosis and management.

Renovascular hypertension (RVH) is defined as an elevated blood pressure caused by kidney hypoperfusion, generally as a result of anatomic stenosis of the renal artery with consequent activation of the Renin Angiotensin-Aldosterone System. The main causes include genetic and inflammatory disorders, extrinsic compression, and idiopathic alterations. RVH is often asymptomatic and should be suspected in any child with refractory hypertension, especially if other suggestive findings are present, including those with severe hypertension, abdominal bruit, and abrupt fall of glomerular filtration rate after administration of angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers. There is a consensus that digital subtraction angiography is the gold standard method for the diagnosis of RVH. Nevertheless, the role of non-invasive imaging studies such as Doppler ultrasound, magnetic resonance angiography, or computed tomographic angiography remains controversial, especially due to limited pediatric evidence. The therapeutic approach should be individualized, and management options include non-surgical pharmacological therapy and revascularization with percutaneous transluminal renal angioplasty (PTRA) or surgery. The prognosis is related to the procedure performed, and PTRA has a higher restenosis rate compared to surgery, although a decreased risk of complications. This review summarizes the causes, physiopathology, diagnosis, treatment, and prognosis of RVH in pediatric patients. Further studies are required to define the best approach for RVH in children.

Radiation-induced kidney toxicity: molecular and cellular pathogenesis.

Radiation nephropathy (RN) is a kidney injury induced by ionizing radiation. In a clinical setting, ionizing radiation is used in radiotherapy (RT). The use and the intensity of radiation therapy is limited by normal-tissue damage including kidney toxicity. Different thresholds for kidney toxicity exist for different entities of RT. Histopathologic features of RN include vascular, glomerular and tubulointerstitial damage. The different molecular and cellular pathomechanisms involved in RN are not fully understood. Ionizing radiation causes double-stranded breaks in the DNA, followed by cell death including apoptosis and necrosis of renal endothelial, tubular and glomerular cells. Especially in the latent phase of RN oxidative stress and inflammation have been proposed as putative pathomechanisms, but so far no clear evidence was found. Cellular senescence, activation of the renin-angiotensin-aldosterone-system and vascular dysfunction might contribute to RN, but only limited data is available. Several signalling pathways have been identified in animal models of RN and different approaches to mitigate RN have been investigated. Drugs that attenuate cell death and inflammation or reduce oxidative stress and renal fibrosis were tested. Renin-angiotensin-aldosterone-system blockade, anti-apoptotic drugs, statins, and antioxidants have been shown to reduce the severity of RN. These results provide a rationale for the development of new strategies to prevent or reduce radiation-induced kidney toxicity.

Hypertension Caused by Renal Arteriovenous Fistula with Multiple Renal Artery Aneurysms.

Renal arteriovenous fistula with renal artery aneurysms and dilated renal veins presents as an infrequent lesion. Endovascular therapy has recently been considered the first-line treatment for these conditions. We report a case of a patient with idiopathic renal arteriovenous fistula concomitant with multiple renal artery aneurysms that was successfully treated by the placement of a covered stent.

Renovascular Hypertension.

Renovascular hypertension (RVH) is relatively common but underrecognized cause of resistant hypertension in clinical practice. Most patients with RVH have suboptimal control of hypertension in spite of being on multiple anti hypertensive medications. Prompt diagnosis and management is crucial to prevent long term morbidity and mortality. Initial evaluation by primary care physicians can expedite this to improve patient outcomes by co-managing hypertension specialists. In addition to pharmacologic and nonpharmacologic measures, some patients may benefit from angioplasty. This article discusses various definitions of hypertension, approach to diagnosis of RVH, and management. Data from clinical trials are discussed with evidence-based medicine practice recommendations.

Management of renovascular hypertension.

PURPOSE OF REVIEW: Renovascular occlusive disease remains a common cause of resistant and rapidly progressive hypertension. The present review summarizes current practice regarding management of renovascular hypertension (RVH). RECENT FINDINGS: Current data using blood oxygen level dependent MR emphasize the tolerance of the kidney to moderate reductions in blood flow and the efficacy of antihypertensive drug therapy for many individuals. Prospective trials have failed to identify benefits of revascularization for moderate disease, either regarding blood pressure or renal function. Antihypertensive drug therapy including renin-angiotensin system blockade is central to management of RVH. Recent and ongoing observational studies report important improvements after revascularization regarding blood pressure, management of refractory or 'flash' pulmonary edema, and survival in specific 'high risk' clinical populations not included in randomized trials. Research directions underscore the role of adjunctive measures, including mitochondrial protection, therapeutic angiogenesis, and cell-based regenerative repair to protect kidney function in RVH. SUMMARY: Clinicians should recognize the potential for disease progression to threaten renal function with severe and prolonged renal ischemia. Improved patient selection for true resistant hypertension with RVH and 'high-risk' clinical manifestations is critical to identify those likely to benefit from renal revascularization.