Renal Stenosis Research Articles

Single-Stage Extracranial and Intracranial Stenting of the Internal Carotid Artery in a Patient with Open Circle of Willis and Associated Renovascular Hypertension

We describe a case of 72-year-old patient with recurrent transient ischemic attacks in the right internal carotid artery (ICA) territory associated with uncontrolled hypertension. Duplex ultrasonography und carotid angiography showed a 60% stenosis with signs of a vulnerable plaque in the cervical segment, as well as a 90% stenosis in the cavernous segment of the right ICA. After further examination the patient was diagnosed with an 80% renal artery stenosis. First, the patient had a single-stage stenting for extracranial and intracranial stenoses of the right ICA, then left renal artery stenting. No intraoperative and postoperative complications were observed. These results show that this surgical treatment is minimally invasive, safe, and effective in symptomatic patients and may be considered for the disease.

Obesity Blunts the Effect of Mesenchymal Stem Cell-Derived Extracellular Vesicles

Mesenchymal stem/stromal cell-derived extracellular vesicles (MSC-EVs) are paracrine vectors with therapeutic functions comparable to their parent cells. However, it remains unclear if donor obesity affects their therapeutic functions. We tested the hypothesis that the curative effect of human adipose tissue-derived MSC-EVs (A-MSC-EVs) is blunted by obesity. MSC-EVs were isolated by ultracentrifugation from mesenchymal stem/stromal cells (MSCs) collected from abdominal subcutaneous fat of obese and lean human subjects (obese and lean-MSC-EVs, respectively) and injected into the aorta of mice 2 weeks after renal artery stenosis (RAS) induction. Magnetic resonance imaging studies were conducted 2 weeks after MSC-EVs delivery to determine renal function. The effect of MSC-EVs on tissue injury was assessed by histology and gene expression of inflammatory factors, including interleukin (IL)-1β, IL-6, monocyte chemotactic protein-1 (MCP-1), and tumor necrosis factor alpha (TNF-α). Oxidative damage, macrophage infiltration, plasma renin, and hypoxia inducible factor-1α (HIF-1α) were also assessed. Tracking showed that MSC-EVs localized in the kidney tissue, including glomeruli and tubules. All MSC-EVs decreased systolic blood pressure (SBP) and plasma renin and improved the poststenotic kidney (STK) volume, but obese-MSC-EVs were less effective than lean-MSC-EVs in improving medullary hypoxia, fibrosis, and tubular injury. Lean-MSC-EVs decreased inflammation, whereas obesity attenuated this effect. Only lean-MSC-EVs decreased STK cortical HIF-1α expression. Obesity attenuates the antihypoxia, antifibrosis, antiinflammation, and tubular repair functions of human MSC-EVs in chronic ischemic kidney disease. These observations may have implications for the self-repair potency of obese subjects and for the use of autologous MSC-EVs in regenerative medicine.

Immediate and long-term results of the use of balloon angioplasty with stenting in the treatment of renal graft arterial stenosis

Aim. To assess the safety and efficacy of percutaneous transluminal balloon angioplasty with stenting for renal graft artery stenosis. Material and methods. From June 2018 to December 2022, 344 kidney transplants from a deceased donor were performed at the surgical clinic of City Clinical Hospital n.a. S.P. Botkin. The study group consisted of 220 men (63.9%) and 124 women (36.1%). The mean age was 46.46±11.74 (19–73) years. With a mean follow-up period of 20.05 (1-54) months, stenosis of the renal graft artery was diagnosed in 4 patients (1.16%). The mean time from transplantation to the diagnosis of stenosis was 4 (1–9) months. In addition, we diagnosed the development of this complication in 4 kidney transplant recipients operated in other centers. The mean time from transplantation to the diagnosis of stenosis in these patients was 103.25 (12–221) months. Thus, we have the experience in the treatment of renal transplant arterial strictures in 8 recipients: 4 men (50%) and 4 women (50%). The mean age was 48.25±11.97 (27–60) years. Stenosis was manifested by renal graft dysfunction with a progressive increase in urea and creatinine in 6 patients (75%), by arterial hypertension in 2 patients (25%). The mean, level of creatinine at the time of diagnosing stenosis was 290.75 (157–494) µmol/L, glomerular filtration rate was 22.87±12.19 (8–41) ml/min/1.73m2 . Results. In the early postoperative period, 1 complication was recorded in the form of pulsating hematoma of the common femoral artery, which required surgical intervention (complication class IIIA according to Clavien-Dindo). The mean hospital postoperative bed-days made 5.22 (4-8). The mean follow-up time was 22.75±7.4 (14–33) months. All recipients were alive throughout the whole follow-up period. In 7 of 8 recipients (87.5%), the graft was functioning, in 1 patient a progressive graft dysfunction was noted, for which chronic hemodialysis was started. Mean creatinine in recipients with a functioning graft was 156.71±33.4 (123–200) µmol/L; mean glomerular filtration rate was 41.57 ml/min/1.73m2 . Conclusions. Percutaneous transluminal balloon angioplasty with stenting is a safe and effective minimally invasive technique and should be considered as the operation of choice in the development of renal graft artery stenosis.

#4682 DOES RENAL ASYMMETRY WITH HYPERTENSION EQUAL RENAL ARTERY STENOSIS?

Abstract Background and Aims Renal ultrasound (US) is a basic imaging study in renal disease with hypertension (HTN) work up. Asymmetry is a frequent finding but it does not equal renal artery stenosis (RAS). Our aim was to describe the incidence of asymmetry findings in our Diagnostic and Interventional Nephrology Unit (DINU) and study its correlation with HTN and RAS. Method Results Conclusion Renal asymmetry is infrequent (2%) and in up to a quarter of those this finding is related to RAS. In our experience, asymmetry associates with hypertension even if no RAS is present: renal asymmetry associates with higher hypertension prevalence and higher medication requirements to reach acceptable blood pressure control.

#5079 THE EVALUATION OF RENAL FUNCTIONAL RESERVE WITH ORAL PROTEIN LOAD OR ULTRASOUND TEST: A REAL-LIFE PERSPECTIVE

Abstract Background and Aims The RFR (renal functional reserve) is the difference between the stimulated glomerular filtration rate (GFR) and the baseline GFR. This difference can be expressed in absolute terms (mL/min) or relative terms (percentage of increment relative to the baseline GFR). This index makes it possible to highlight a subclinical renal functional deterioration when the laboratory values of creatinine are still within the normal range. Measurement of RFR by protein load (1 g/kg of oral protein) (RFR-T) is now considered the gold standard for RFR assessment. RFR measured with protein load (RFR-T) predicts the risk of acute kidney injury (AKI) or chronic kidney disease (CKD) in both healthy and diseased patients and is particularly useful in patients with apparently normal renal function before stress candidate for interventions at real risk of renal failure (kidney donors, cardiac surgery, bone marrow transplants). However, the protein load test has a long duration (about 5 hours), requires numerous blood and urine samples, and is challenging to use on a large scale. Recent studies have proposed another method based on the variation of the renal intraparenchymal resistance index (IRRIV-T). In this case, the stress to which the kidney is mechanical. That is a weight (saline bag, representing 10% of the body weight) placed on the abdomen of the supine patient, which induces maximal renal vasodilation. The sampling of the intraparenchymal resistance doppler indices before and after the weight application would correlate, in preliminary studies, with the RFR tested with the protein load. Thus, offering a fast and non-invasive method. Eventually, comparing these divergent diagnostic procedures can guide us in choosing the most cost-effective approach to gain deeper insight into renal health. (Fig. 1) Method Our cross-sectional study aimed to compare the classic protein loaded RFR test (RFR-T) with the new IRRIV ultrasound test (IRRIV-T). This real-life study includes a normal-renal function population of 42 patients. Anthropometric parameters and cardiovascular risk factors were evaluated, and blood and urinary tests were performed. The inclusion criteria were: (i) age greater than 18 years; (ii) eGFR CKD-EPI > 60 mL/min/1.73 m2. Exclusion criteria were: (i) non-steroidal inflammatory drugs (NSAIDs), (ii) ultrasound evidence of renal morphological changes or artery stenosis. Each patient underwent oral protein load testing (RFR-T) and an ultrasound test (IRRIV-T). Pearson's correlation index analyzed the comparison between the 2 tests. Results There was no statistically significant correlation between RFR-T and IRRIV-T in terms of the RFR either in absolute numbers (R = 0.14, p = 0.37) or in percentage values (R = 0.15, p = 0.33). (Fig. 2) Based on our experience, the IRRIV test proved unreliable in evaluating RFR compared with the gold standard (RFR-T). Therefore, not suitable to be used as a possible alternative to the oral protein load test. Conclusion Unlike previous studies, our survey is a real-life study. Many of our patients have pathologies or take drugs that could alter the hemodynamic and the renal vascular response, consequently changing the outcome of the IRRIV test. However, it is a real-life experience that aims to offer a practical point of view, bringing to light the possible limitations of the ultrasound test when applied to a standard evaluation population and not to a healthy or highly selected population as in the only three previous works published in the literature up to now. Our work is the first original real-life study in this field.

#6465 MIR-451B AND CHRONIC KIDNEY DISEASE: A NOVEL TARGET TO MODULATE RENAL VEGF SIGNALING

Abstract Background and Aims Chronic kidney disease (CKD) is a progressive disorder that affects over 15% of adults worldwide. A major component of CKD pathophysiology is renal microvascular rarefaction and loss that pairs the progression of the disease and complications. We developed a translational swine model of CKD and showed that loss of renal function associates with a significant decrease in renal vascular endothelial growth factor (VEGF) signaling and progressive microvascular (MV) rarefaction. VEGF is a key endogenous cytokine for MV proliferation and repair, but underlying mechanisms of renal VEGF downregulation in CKD are unknown. We hypothesized that micro-RNA (miRNA)-mediated processes contribute to the downregulation of renal VEGF signaling in CKD. Method Unbiased renal micro-RNA (miRNA)-seq was performed in a swine model of CKD stage 3 (14 weeks of bilateral renal artery stenosis + atherogenic diet) and normal controls (n = 5/group). Micro-RNAs up- (>1.4 FC, p<0.05) and down-regulated (<0.7 FC, p<0.05) were identified, followed by target prediction analysis (miRwalk 3.0, Target Scan 7.2). Renal gene and protein expression of VEGF was measured by qPCR and western blot, respectively, and renal MV architecture was studied by 3D micro-CT. Results Unbiased miRNA-seq and target prediction analysis identified four miRs upregulated in the kidney of CKD pigs vs. controls, of which miR-451b (validated by qPCR), broadly conserved among species, was capable of targeting VEGFA (FC = 4.46, p = 0.04). Renal gene and protein expression of VEGF was downregulated in CKD vs. controls, associated with significant cortical and medullary microvascular rarefaction (Figure 1). Conclusion Our data suggest that post-transcriptional modulation of renal VEGF signaling may serve as a prominent mechanism of VEGF downregulation, which leads to MV rarefaction and disease progression in CKD. Furthermore, this work in progress identified a novel candidate (miR-451b) and may set the stage for its targeted modulation to preserve VEGF signaling as a potential strategy to protect the renal microvasculature in CKD.

#5555 TAKAYASU ARTERITIS IN THE TIME OF SARS-COV-2

Abstract Background and Aims SARS CoV 2 infection is characterized by pulmonary, cardiovascular, neurological and other complications. New onset hypertension after SARS Cov 2 infection was observed in various studies with an unclear mechanism. Vessel inflammation is a common finding in these patients. Case A young woman (24 years old) referred to our Unit for high blood pressure levels appeared few days after SARS COVID 2 infection. She had a positive familiar history of hypertension. A 24 hours blood pressure monitoring confirmed hypertension and the patient was treated with a beta-blocker and referred to the nephrologist. Physical examination was negative and peripheral pulses were palpable. Blood pressure was 150/90 mmHg without significative discrepancy (<10 mmHg) between right and left arm and between upper and lower limbs. Carotid-femoral and carotid-radial pulse wave velocity was in the upper limit of the normal range (9.8 and 8.0 m/sec respectively), renal function was preserved (serum creatinine 0.6 mg/dl, eGFR 154 ml/min) and proteinuria was 450 mg/die. C-reactive protein was 13 mg/L. Complement components C3 and C4 as well as IgG and anti-neutrophil cytoplasmic antibody (ANCA) levels were in the normal range. IgA and IgM were slightly elevated and anti-nuclear antibody (ANA) levels were 1:160. TSH was in the normal range. Patient was switched to calcium channel blockers and a screening to exclude secondary hypertension was performed. Hormonal profile showed hypersecretion of cortex and medullary adrenal gland (high renin and aldosterone, plasma and urinary cortisol, and epinephrine levels). Patient was treated with ACE inhibitor and showed an optimal blood pressure profile. Abdominal-Chest CT angiography detected no increase in adrenal gland dimension. Conversely, a left renal artery stenosis and a mild enlargement of the para-aortic tissue, suggestive of a retroperitoneal fibrosis, was described (Figure 1). A Doppler ultrasound examination confirmed a high systolic peak velocity in left renal artery and a low resistive index in the left kidney. According to the diagnosis of renal fibrosis, patient was treated with oral prednisone at a dosage of 1 mg/Kg/BW. Three months later, Doppler ultrasound and CT were materially unchanged. After a case revision and a negative evidence of inflammation at PET-FDG examination, the Takayasu Arteritis diagnosis was formulated and the patient underwent left renal artery angioplasty. Oral prednisone was tapered and methotrexate was started. One month later blood pressure and Doppler ultrasound velocimetric parameters were normalized. Conclusion This case report suggests that Takayasu arteritis may occur after SARS COVID 2 infection.

#6682 RENAL ARTERY STENOSIS: A SINGLE CENTRE STUDY

Abstract Background and Aims Renal artery stenosis (RAS) is present from 1% to 5% in people affected by arterial hypertension and it is often associated with peripheral artery disease and coronary artery disease; as the matter of fact, it is commonly found in people undergoing cardiac catheterization (18-20%) or angiography for aorto-iliac and lower extremities diseases. The major cause of renal artery stenosis is an atherosclerotic lesion localized in the proximal segment or to the ostium. Clinical presentations are renovascular hypertension and ischemic nephropathy. The aim of the study is to define either endovascular treatment gives a significant benefit on renal function and blood pressure control, when associated to medical therapy. Method This is a retrospective study focused on patients who underwent renal artery angioplasty and stenting in the last ten years, from November 2011 to April 2021 in the Nephrology Department, at Sant'Andrea Hospital, La Spezia (Italy). The primary outcome was kidney function, while secondary outcomes were blood pressure and the number of antihypertensive drugs one year after the revascularization. Patients included in the study had uncontrolled and refractory arterial hypertension (PA ≥140/90 mmHg) and/or progressive worsening of renal function, secondary to bilateral or unilateral stenosis in one functional kidney, that was identified at the color-doppler ultrasound examination by a peak systolic velocity (PSV) >200 ml/min and an aortic-renal ratio >3,5. We found 36 patients who had these characteristics. They were all affected by chronic kidney disease (CKD) (mean±SD eGFR 25,3±15,3 ml/min/1,73 m2) equally divided into stage 3 (33%, eGFR 30-60 ml/min/1,73 m2), stage IV (31% eGFR 15-29 ml/min/1,73 m2) and stage V (36%, eGFR <15 ml/min/1,73 m2). Results Kidney function, measured as serum creatinine (SCr) (mg/dl), improved immediately after the revascularization (mean ± SD SCr after vs before 2,52 ± 1,61 vs 3,31 ± 2,47 mg/dl p<0.05), after 30 days (mean ± SD SCr after vs before creat. 2,36 ± 1,53 vs 3,19 ± 2,39 mg/dl p<0.05) and after one year (mean ± SD SCr after vs before creat. 2,04 ± 1,16 vs 2,99 ± 2,40 mg/dl p<0.05) (Fig. 1). Regarding arterial hypertension, a significant reduction of both systolic (SBP) and diastolic (DBP) blood pressure was detected in the subgroup of people under 75 years old (mean ± SD SBP after vs before, 144,62 ± 12,55 vs 168,18 ± 36,40 mmHg, p< 0,01; after one year vs before, 143,95 ± 21,10 vs 167,83 ± 38,16 mmHg, p<0.05) (mean ± SD DBP after vs before, 73,62 ± 9,62 vs 83,07 ± 21,75 mmHg, p< 0,05; after one year vs before 75,20 ± 9,02 vs 83,33 ± 23,10 mmHg, p = 0.07) (Fig. 2). The number of antihypertensive drugs dropped immediately after the angioplasty (mean ± SD tablets after vs before 2,28 ± 1,11 vs 3,21 ± 1,43, p<0.01), while after one year there was not a significant increase of therapy (mean ± SD tablets after one year vs before, 3,00 ± 1,41 vs 3,23 ± 1,42, p = 0,47), even if blood pressure was better controlled than before the procedure with the same amount of tablets (Fig. 3). Conclusion Although our population was quite small, we demonstrated the advantages of renal artery revascularization in atherosclerotic renovascular disease, as demonstrated by kidney function and blood pressure control. Our results contrast the larger studies considered, that found no relevant clinical benefit on renal function and incidence of major adverse cardiovascular and renal events by comparing patients treated with medical therapy alone or with medical therapy plus angioplasty. The different conclusions are probably due to our strict adhesion to the endovascular treatment indications, which consider the revascularization as the optimal strategy for a well-defined population.

Contemporary and Emerging MRI Strategies for Assessing Kidney Allograft Complications: Arterial Stenosis and Parenchymal Injury, From the AJR Special Series on Imaging of Fibrosis.

MRI plays an important role in the evaluation of kidney allografts for vascular complications as well as parenchymal insults. Transplant renal artery stenosis, the most common vascular complication of kidney transplant, can be evaluated by MRA using gadolinium and nongadolinium contrast agents as well as by unenhanced MRA techniques. Parenchymal injury occurs through a variety of pathways, including graft rejection, acute tubular injury, BK polyomavirus infection, drug-induced interstitial nephritis, and pyelonephritis. Investigational MRI techniques have sought to differentiate among these causes of dysfunction as well as to assess the degree of interstitial fibrosis or tubular atrophy (IFTA)-the common end pathway for all of these processes-which is currently evaluated by invasively obtained core biopsies. Some of these MRI sequences have shown promise in not only assessing the cause of parenchymal injury but also assessing IFTA noninvasively. This review describes current clinically used MRI techniques and previews promising investigational MRI techniques for assessing complications of kidney grafts.

Bilateral renal artery stenosis impacts postoperative complications after major vascular surgery

BackgroundIncidental atherosclerotic renal artery stenosis (RAS) is common in patients undergoing vascular surgery and has been shown to be associated with postoperative AKI among patients undergoing major non-vascular surgeries. We hypothesized that patients with RAS undergoing major vascular procedures would have a higher incidence of AKI and postoperative complications than those without RAS. MethodsA single-center retrospective cohort study of 200 patients who underwent elective open aortic or visceral bypass surgery (100 with postoperative AKI; 100 without AKI) were identified. RAS was then evaluated by review of pre-surgery CTAs with readers blinded to AKI status. RAS was defined as ≥50 % stenosis. Univariate and multivariable logistic regression was used to assess association of unilateral and bilateral RAS with postoperative outcomes. Results17.4 % (n = 28) of patients had unilateral RAS while 6.2 % (n = 10) of patients had bilateral RAS. Patients with bilateral RAS had similar preadmission creatinine and GFR as compared to unilateral RAS or no RAS. 100 % (n = 10) of patients with bilateral RAS had postoperative AKI compared with 45 % (n = 68) of patients with unilateral or no RAS (p < 0.05). In adjusted logistic regression models, bilateral RAS predicted severe AKI (OR 5.82; CI 1.33, 25.53; p = 0.02), in-hospital mortality (OR 5.71; CI 1.03, 31.53; p = 0.05), 30-day mortality (OR 10.56; CI 2.03, 54.05; p = 0.005) and 90-day mortality (OR 6.88; CI 1.40, 33.87; p = 0.02). ConclusionsBilateral RAS is associated with increased incidence of AKI as well as in-hospital, 30-day, and 90-day mortality suggesting it is a marker of poor outcomes and should be considered in preoperative risk stratification.

Using Ultrahigh b -Value Diffusion-Weighted Imaging to Noninvasively Assess Renal Fibrosis in a Rabbit Model of Renal Artery Stenosis.

This study aimed to investigate the feasibility of diffusion-weighted imaging with ultrahigh b values ( ub DWI) for the evaluation of renal fibrosis (RF) induced by renal artery stenosis (RAS) in a rabbit model. Thirty-two rabbits underwent left RAS operation, whereas 8 rabbits received sham surgery. All rabbits underwent ub DWI ( b = 0-4500 s/mm 2 ). The standard apparent diffusion coefficient (ADC st ), molecular diffusion coefficient ( D ), perfusion fraction ( f ), perfusion-related diffusion coefficient ( D *) and ultrahigh apparent diffusion coefficient (ADC uh ) were longitudinally assessed before operation and at weeks 2, 4, and 6 after operation. The degree of interstitial fibrosis and the expression of aquaporin (AQP) 1 and AQP2 were determined through pathological examination. In the stenotic kidney, the ADC st , D , f , and ADC uh values of the renal parenchyma significantly decreased compared with those at baseline (all P < 0.05), whereas the D * values significantly increased after RAS induction ( P < 0.05). The ADC st , D , D *, and f were weakly to moderately correlated with interstitial fibrosis as well as with the expression of AQP1 and AQP2. Furthermore, the ADC uh negatively correlated with interstitial fibrosis ( ρ = -0.782, P < 0.001) and positively correlated with AQP1 and AQP2 expression ( ρ = 0.794, P < 0.001, and ρ = 0.789, P < 0.001, respectively). Diffusion-weighted imaging with ultrahigh b values shows the potential for noninvasive assessment of the progression of RF in rabbits with unilateral RAS. The ADC uh derived from ub DWI could reflect the expression of AQPs in RF.

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.

Rapidly reversible acute neurological, renal, and cardiac impairment during malignant hypertension

BackgroundMalignant hypertension is a model of the rapid changes that a high afterload and renin-angiotensin levels can induce on target organs such as the heart. We present a case of a young man affected by malignant hypertension with multi-organ involvement who showed quick remission after adequate antihypertensive treatment.Case summaryA 41-year-old jazz pianist with a family history of coronary artery disease presented to the emergency department for asthenia and epigastric pain, associated with right eye visual impairment. No neurological symptoms. An echocardiogram showed left ventricular hypertrophy with severe impairment of ejection fraction (22%) due to global hypokinesia. There was renal insufficiency (creatinine 2.51 mg/dl, eGFR 34 ml/min, HS Troponin T 127 pg/dl, NT pro-BNP 22,672 pg/ml, CRP 32 mg/L, sodium 129 mEq/L with normal kaliemia. The following day, anterior T wave inversion was observed in the electrocardiogram. At a cardiac magnetic resonance. Concentric hypertrophy of the left ventricle was observed with normal myocardial T1 mapping values (1100 ± 38 ms), ruling out Fabry’s disease. There was no obvious myocardial edema at T2 weighted. The viral panel for acute myocarditis resulted in negative. After the exclusion of all possible secondary causes, malignant essential hypertension was the final diagnosis, and additional tests confirmed multi-organ damage. An ophthalmological examination demonstrated hypertensive retinopathy with hemorrhages, cottony exudates, and macular lipid exudation, especially in the right eye. A brain MRI showed small areolas of T2 hyperintensity in the white matter of both cerebral hemispheres, suggestive of chronic microangiopathy, and left nuclear micro lacunar ischemia.The patient was treated with full-dose calcium channel blockers (amlodipine 10 mg), beta-blockers (bisoprolol 10 mg), alpha2 agonists (slow-release clonidine patch), selective a1 blocker (doxazosine 16 mg), and furosemide 50 mg. After the exclusion of renal stenosis and improvement of renal function, Ramipril was added up to a final dose of 10 mg daily. In parallel with the achievement of a satisfactory blood pressure control, visual impairment disappeared with a reduction of retinal ischemic exudates and hemorrhages at the ophthalmological follow-up assessment.At the time of discharge, an echocardiographic re-evaluation confirmed concentric hypertrophy of the left ventricle with markedly reduced wall thicknesses, with a partial recovery in left ventricular ejection function (EF 44%).Six months after discharge, the patient is in good general condition under optimal medical therapy (without furosemide) with normalized blood pressure values (130–140/80 mmHg). At 6 months from discharge, creatinine was only mildly increased (1.5 mg/dl, eGFR 59.5 ml/min) and NT-pro BNP nearly normalized (452 pg/ml).DiscussionMalignant hypertension is a cardiovascular emergency and requires immediate and careful intervention to lower blood pressure and reduce organ injury. It is an exclusion diagnosis that can be advanced once the causes of secondary hypertension have been excluded. Remission of organ injury is possible and might be rapid under adequate antihypertensive treatment, but patients require a close follow-up.

One-Stage CABG and Renal Artery Stenting: A One-Stop Treatment Protocol

Coronary artery disease and renal artery stenosis have significant associations. During coronary angiography and preoperative work-up, renal artery screening is a regular practice. The patients with renal artery stenosis have a very high incidence of uncontrolled hypertension. The treatment is often generally divided into two or three parts, with separate admissions. Having a hybrid cardiac operation suite provides a great opportunity to perform all the procedures in the same admission.

TRANSLUMINAL ANGIOPLASTY OF THE RENAL ARTERIES IN PATIENTS WITH FIBROMUSCULAR DYSPLASIA

Objective: FMD is the second most frequent cause of renal artery stenosis (RAS) after atherosclerosis and can lead to hypertension. To cure or improve this renovascular hypertension, patient with fibromuscular dysplasia and renal artery stenosis undergo renal artery revascularization by percutaneous renal transluminal angioplasty (PTRA). Although this method has been performed for many years, there have been only few small size trials published. This retrospective single center study aimed to evaluate the rate of cured hypertension after PTRA. Design and method: We included all adult patients diagnosed with FMD who were seen in our referral center for hypertension management (Hôpital Européen Georges Pompidou, Paris) from January 2010 to March 2020. Blood pressure response was assessed at 3 month and one year. Primary outcome was one year cured hypertension rate in ambulatory measurement, secondary outcomes were improvement and complication rate. Results: Overall, 76 adult patients (87% female, mean age at enrollment 35.5 years) were included. FDM was multifocal in 74% and unisite in 68% of patients. AT baseline, mean day ambulatory blood pressure (dABP) was 141 ± 17/89 ± 14 mmHg under a mean of 2.3 ± 1.37 antihypertensive treatments. All patient underwent PTRA. Stent were inserted in 8 patients (10.5%) with residual stenosis after PTRA and in 8 patients (10.5%) with renal artery dissection, total complication rate was 18.4%. At one-year follow-up, mean dABP was 128 ± 12/78 ± 9 mmHg (p &lt; 0.0001) with 1.1 ± 1.3 treatments (p &lt; 0.0001). In total, 75% beneficiated from renal angioplasty: 31% were cured and 44% were improved. Cured hypertension was associated with low body mass index (BMI) (p = 0.017) and unisite FDM (p = 0.017) on a multivariable analysis. Conclusions: In patients with FMD, PTRA is associated with cured hypertension 31% of patients with renal artery FMD undergoing PRTA. Hypertension is more likely to be cured in patient with low BMI and multisite FMD. These results are to be put in perspective with a complication rate of 18.4%.

MULTIPLE RENAL ARTERIES AS A RISK FACTOR FOR SEVERE HYPERTENSION IN YOUNG ADULTS?

Objective: The significance of multiple renal arteries (MRAs) in arterial hypertension (AH) is not fully understood. Lower perfusion pressure due to longer length and narrower caliber of MRAs could cause segmental hyperreninemia sufficient to result in renin-dependent systemic hypertension. Sympathetic renal nerve activity might be affected by hyperreninema as well. The aim of the study was to examine the characteristics of young adult hypertensives in relation to the existence of MRAs that were diagnosed during evaluation for secondary arterial hypertension. Design and method: 32 patients underwent routine evaluation for secondary hypertension and target organ damage. Patients were divided into two groups, one with MRAs and the other without MRAs. Data were presented as mean +standard deviation and compared by the Indipendent-Sample t-test. Results: The mean age was 38 years, and 13 patients were diagnosed with MRAs. There were more men in the MRAs group, otherwise, there were no significant differences in baseline characteristics between the groups (BMI, smoking, family history). None of them were diagnosed with secondary endocrine hypertension or renal artery stenosis. MRAs group showed significantly higher values of office SBP/DBP (p &lt; 0,012) and 24-hour SBP/DBP (p &lt; 0,001), and nonsignificantly higher values of heart rate. Although nonsignificant, direct renin concentrations were slightly higher in the MRAs group, while insulin levels were higher in the non-MRAs group. Dyslipidemia was diagnosed in most patients, without significant differences between groups. Electrocardiographic and echocardiographic changes suggesting hypertensive heart remodeling were found in 55% of patients in MRAs compared to 32% in non-MRAs, there were no significant differences in NTproBNP levels. A nonsignificant reduction in glomerular filtration rate was noticed in the MRAs group, while there were no significant differences in 24-hour albuminuria (p 0,308; p 0,614). Conclusions: The significance of MRAs in arterial hypertension is a matter of debate. In our study of young patients with arterial hypertension and MRAs, we observed features of more severe hypertension with already existing hypertensive target organ damages. Proper medical treatment with antihypertensive agents is crucial. Future studies will answer the question about interventional therapeutic procedures’ role in preventing cardiovascular complications.

THE RISKS AND BENEFITS OF RENAL ARTERY STENTING IN FIBROMUSCULAR DYSPLASIA. LESSONS FROM ARCADIA-POL STUDY

Objective: Percutaneous transluminal angioplasty (PTA) is the recommended revascularization strategy in patients with renal artery stenosis (RAS) caused by fibromuscular dysplasia (FMD), limiting stenting to complications management. However this recommendation is based on cases reports and small series. The main aim of the study was to retrospectively analyze immediate and long-term results of renal stenting and PTA in FMD patients. The second aim was to evaluate the results of stenting as support of renal artery aneurysm (RAA) closure. Design and method: The study group consisted of 58 patients percutaneously treated due to significant RAS (70 arteries) and 9 patients (10 RAAs) with a history of stent implantation before aneurysm embolization, derived from 343 ARCADIA-POL registry patients. PTA was performed as initial treatment in 61 arteries (PTA-group), whereas primary stenting was done in 9 arteries (STENT-group). Stent-related complications(SRC) were defined as: in-stent restenosis (&gt;50%) or occlusion (ISR/O); stent fracture; stent underexpansion (SU) or migration. Results: In PTA-group, the first restenosis rate was 50.8%. Subsequently, 22 arteries underwent a second procedure: re-PTA(12 arteries) or stent implantation(10 arteries) . The incidence of recurrent restenosis after re-PTA was 41.7%. In the 10 arteries initially treated with PTA that underwent stenting for restenosis, complications occurred in 7 of them (70%), including 2 SUs and 5 ISR/Os . In STENT-group, SU occurred in one case (11.1%) and in-stent restenosis in 33.3% (3 of 9 stents). In combined analysis, SRC occurred following 11/19 stenting procedures (57.9%) including 3 periprocedural (SUs) and 8 late complications (ISR/Os). Finally, despite several subsequent revascularization attempts, 4 of 19 (21%) stented arteries were totally occluded and one remained significantly stenosed at follow-up imaging (Figure). In contrast to FMD-RAS procedures, there was only one intraprocedural complication (partial stent migration) and no late SRC in RAA patients. Conclusions: Renal artery stenting in FMD provides modest benefit in terms of restenosis prevention but poses high risk of immediate and late complications, including stent occlusion. Our study supports recommendations limiting stenting to the management of complications. In contrast, renal artery stenting in FMD RAA closure is associated with favorable long-term outcomes.

Nefropatías vasculares: hipertensión vasculorrenal y nefropatía isquémica. Enfermedad tromboembólica y trombosis venosa renal

Vascular nephropathy is a term that covers the renal alterations associated with vascular pathology. One of the most representative entities is stenosis of the main renal artery, which often gives rise to secondary hypertension and a reduction in blood flow to the kidneys, leading to deterioration in their functioning. When this occurs it is denominated ischemic nephropathy. The most common aetiology for this is arteriosclerosis, although in young patients fibromuscular dysplasia is the most frequent cause. It should be diagnosed early, individualizing the imaging technique used depending on the degree of suspicion and the presence or not of kidney failure. Treatment should aim to control blood pressure as well as to preserve kidney functioning. Together with pharmacological treatment, angioplasty with or without placing a stent and surgical repair may be indicated in some cases.Thromboembolism of the main renal artery is a rare disease that mainly occurs in patients with a history of auricular fibrillation, and it may cause renal infarct. In atheroembolic kidney disease the small arteries of the kidneys are blocked by cholesterol crystals which have separated from atheroma plaques in the large arteries. It affects patients with severe arteriosclerosis and progresses with multisystem damage. Thrombosis of the renal vein is another rare pathology which affects patients with nephrotic syndrome more often.

AORTIC INVOLVEMENT IN FIBROMUSCULAR DYSPLASIA: REPORT FROM ARCADIA-POL

Objective: Fibromuscular dysplasia (FMD) affects the walls of medium-sized arteries. There are no described radiological characteristics pathognomonic of aortic FMD but pathological documentation of aortic FMD has been occasionally reported. The aims of this study were to investigate the characteristics of abdominal aorta in patients with FMD versus controls and to review the relevant literature. Design and method: We measured centreline abdominal aortic diameters on 136 patients with FMD (22 with focal disease) enrolled in the ARCADIA-POL study, 60 patients with carotid dissections but no evidence of FMD and 136 healthy controls. Results: The median abdominal aortic diameter did not differ between patients with FMD, patients with carotid dissections and no evidence of FMD and healthy controls. However, aortic diameter at the level of the diaphragm was smaller in patients with focal FMD compared to patients with multifocal FMD, patients with carotid dissections and healthy controls (ANOVA 0.015). Six patients with mid-aortic syndrome (MAS) were reported separately. All had radiological evidence of FMD in medium-sized aortic branches. In one in whom a sample of aortic wall was obtained, histology confirmed focal aortic FMD. A literature review found a further 31 reports of aortic histology with features of FMD. Conclusions: We found no difference in aortic diameters between individuals with or without FMD. Nevertheless, patients with focal FMD had smaller aortic diameters than those with multifocal FMD and controls. This represents another phenotypic difference between multifocal and focal FMD. Focal renal artery stenosis associated with MAS may represent an extreme presentation belonging to the same disease spectrum.

POOLED, 6-MONTH SAFETY AND EFFICACY RESULTS USING THE SYMPLICITY SPYRAL RADIOFREQUENCY RENAL DENERVATION CATHETER

Objective: Over 1,200 patients received renal denervation (RDN) to reduce high blood pressure using the current generation, multi-electrode, radiofrequency Symplicity SpyralTM catheter as part of the SPYRAL HTN Global Clinical Program. The Spyral FIM was a prospective, single-arm study to assess feasibility. The SPYRAL HTN-OFF MED and -ON MED studies were randomized, sham controlled, blinded trials assessing the safety and efficacy of RDN in the absence and presence of antihypertensive medications, respectively. The Global SYMPLICITY Registry is an all-comer, global, single-arm study assessing safety and efficacy of RDN in a real-world setting with patients on various medication regimens. Here, we present the pooled, 6-month efficacy and safety results of RDN using the Spyral catheter. Design and method: At each follow-up, including at 6 months, office systolic and diastolic blood pressures and 24-h ambulatory systolic and diastolic were collected. Adverse safety events and other indicators including estimated glomerular filtration rate (eGFR) and incidence of renal artery stenosis were recorded. GSR was an all-comer registry for patients with uncontrolled hypertension, whereas patients in the SPYRAL HTN-OFF and ON MED trials were required to have an OSBP &gt; = 150 and &lt;180 mmHg and ODBP &gt; = 90 mmHg. Results: As of December 19, 2022, 1,298 patients have received RDN therapy using the Spyral catheter, including eligible control patients from the randomized trials who elected to cross over to receive RDN after unblinding. Mean, 6-month reductions in office and 24-h ambulatory BP from baseline are shown in the Figure. Patients had similar, significant reductions in diastolic blood pressure from baseline through 6 months. Including crossover patients, eGFR decreased by 1.5 mL/min/1.73 m2 through 6 months in RDN patients using the SPYRAL catheter (n = 962; 95% CI: -2.27,-0.74; p &lt; 0.001). There have been no recorded instances of renal artery stenosis &gt;70% through 6 months. Conclusions: Patients receiving RDN had significant and consistent 6-month reductions in BP compared to baseline measures. There have been no incidences of renal artery stenosis, and reductions in eGFR are consistent with natural progression with age. These results highlight the efficacy and safety of RDN using the current generation Spyral catheter.