Overview on Renovascular Hypertension: Review Article

Renovascular hypertension (RVH) is a prevalent cause of secondary hypertension that frequently develops to resistant hypertension. It is characterised as systemic hypertension that develops as a result of a restricted blood supply to the kidneys. Patients cannot be recognized clinically from those with essential hypertension; therefore, diagnosis requires arteriography, however urography and isotope renography may hint to the diagnosis. Atherosclerotic renal artery stenosis (ARAS) and fibromuscular dysplasia are the two most prevalent causes of RVH. The ultimate objective of controlling RVH, like with other kinds of hypertension, is to minimize the morbidity and mortality associated with high blood pressure The widespread use of effective antihypertensive medication treatment, statins, and other strategies to control vascular disease has resulted in remarkable improvements. In this review we will be looking at etiology, pathogenesis and treatment or RVH.

Percutaneous Revascularization for Atherosclerotic Renal Artery Stenosis: a Meta-analysis

Objective: This study aimed to investigate whether percutaneous revascularization (PR) was as effective and safe as medication therapy alone in patients with atherosclerotic renal artery stenosis (ARAS).Methods: We searched Embase, PubMed, and the Cochrane Library databases from their inception to July 31, 2021. We included randomized controlled trials (RCTs) reporting PR for ARAS. RevMan 5.3 was employed to conduct the analysis.Results: Of 469 screened studies, 9 were included in our study. A total of 2433 patients with ARAS were recorded. The results demonstrated that PR and medication had a similar antihypertensive effect on both systolic [mean difference (MD)= 0.37, 95% CI: -1.37 to 2.11, p= 0.68] and diastolic blood pressure (MD= -0.75, 95% CI: -2.84 to 1.34, p= 0.48). Meanwhile, there were no differences in all-cause mortality [risk ratio (RR) = 0.90, 95% CI: 0.74-1.10, p=0.31)], stroke (RR = 0.81, 95% CI: 0.53-1.98, p=0.32), congestive heart failure (RR = 0.89, 95% CI: 0.70-1.14, p= 0.36), and periprocedural complications (RR = 0.89, 95% CI: 0.72-1.10, p=0.28).Conclusions: The results revealed that PR was as effective and safe as medication therapy alone in patients with ARAS.

Atherosclerotic Renal Artery Stenosis: A Review

Renal artery stenosis (RAS) is associated with hypertension and renal impairment. Atherosclerosis is the leading etiologic factor which accounts for >90% of the cases. Those with atherosclerotic RAS (ARAS) tend to have concomitant atherosclerosis in other vascular beds, so they are at a high risk of adverse coronary and cerebrovascular events. Management of ARAS is controversial, with limited indications for revascularization. In this review, the author aims to discuss the pathophysiology, natural history, diagnosis, and management of ARAS.

Ischemic Nephropaty: The Role of the Renal Artery Stenosis Revascularization on Renal Stem Cells

We report the case of a 65-year-old man with acute GFR decline to 37 mL/min and uncontrolled high blood pressure. He was suspected for renovascular hypertension and underwent a renal color Doppler ultrasound scan that detected a bilateral atherosclerotic renal artery stenosis. A digital selective angiography by percutaneous transluminal angioplasty and stenting (PTRAs) was successfully performed. Blood pressure rapidly normalized, GFR increased within a few days, and proteinuria disappeared thereafter. These clinical goals were accompanied by a significant increase of circulating renal stem cells (RSC) and a slight increase of resistive index (RI) in both kidneys. This single observation suggests the need for extensive studies aimed at evaluating the predictive power of RI and RSC in detecting post-ischemic renal repair mechanisms.

Preoperative clinical and renal ultrasonography variables associated with improved systolic and diastolic blood pressure reduction after renal artery stenting

IntroductionResponse to stent-assisted angioplasty (PTA) in hypertensive patients with atherosclerotic renal artery stenosis (ARAS) is unpredictable. Therefore, the present study aimed to search for preoperative clinical and renal ultrasonography variables associated with systolic (SBP) and diastolic blood pressure (DBP) reduction.Material and methodsPreoperative clinical assessment and renal ultrasonography were performed in 202 patients who underwent PTA for ARAS (2003–2018). Patients were categorized as responders if decrease of SBP of at least 20mmHg or DBP of 5mmHg was achieved. Logistic regression models, with percentage shares, were evaluated by basic decision characteristics for ultrasonographic and clinical variables.ResultsLogistic regression analysis showed that preoperative SBP ≥145mmHg (OR,20.0 [95%CI 8.67–46.2], p<0.001), (2) baseline DBP >82 mmHg (OR,3.46 [95%CI 1.61–7.42], p=0.001), (3) prior myocardial infarction (OR,3.14 [95%CI 1.09–9.0], p=0.033), and (4) Renal-Aortic-Ratio >5.1 (OR,2.67 [95%CI 1.20-6.0], p=0.016) predicted the SBP response, with respective influence shares of 69.8%; 12.1%; 10.9%; and 7.2%. The DBP response was associated with (1) baseline SBP >145mmHg (OR,3.79 [95%CI 1.87–7.70], p<0.001), (2) baseline DBP >82mmHg (OR,6.09 [95%CI 2.88–12.9], p<0.001), (3) ARAS progression (OR,0.32 [95%CI 0.09–1.07], p=0.062), (4) contralateral kidney length>106mm (OR,0.43 [95%CI 0.22–0.86], p=0.017), and (5) bilateral PTA (OR,2.39 [95%CI 1.08–5.27], p=0.03), with respective shares of 21.8%; 35.0%; 18.2%; 13.3% and 11.8%.ConclusionsCurrent study identified clinical and ultrasonographic characteristics of patients who are likely to respond to PTA for ARAS. The RAR and contralateral kidney size may enhance prediction of response likelihood.

Hypoxic preconditioning induces epigenetic changes and modifies swine mesenchymal stem cell angiogenesis and senescence in experimental atherosclerotic renal artery stenosis

Background Atherosclerotic renal artery stenosis (ARAS) is a risk factor for ischemic and hypertensive kidney disease (HKD) for which autologous mesenchymal stem cell (MSC) appears to be a promising therapy. However, MSCs from ARAS patients exhibit impaired function, senescence, and DNA damage, possibly due to epigenetic mechanisms. Hypoxia preconditioning (HPC) exerts beneficial effects on cellular proliferation, differentiation, and gene and protein expression. We hypothesized that HPC could influence MSC function and senescence in ARAS by epigenetic mechanisms and modulating gene expression of chromatin-modifying enzymes. Methods Adipose-derived MSC harvested from healthy control (N = 8) and ARAS (N = 8) pigs were cultured under normoxia (20%O2) or hypoxia (1%O2) conditions. MSC function was assessed by migration, proliferation, and cytokine release in conditioned media. MSC senescence was evaluated by SA-β-gal activity. Specific pro-angiogenic and senescence genes were assessed by reverse transcription polymerase chain reaction (RT-PCR). Dot blotting was used to measure global genome 5-hydroxymethylcytosine (5hmC) levels on DNA and Western blotting of modified histone 3 (H3) proteins to quantify tri-methylated lysine-4 (H3K4me3), lysine-9 (H3K9me3), and lysine-27 (H3K27me3) residues. Results Specific pro-angiogenic genes in ARAS assessed by RT-PCR were lower at baseline but increased under HPC, while pro-senescence genes were higher in ARAS at baseline as compared healthy MSCs. ARAS MSCs under basal conditions, displayed higher H3K4me3, H3K27me3, and 5hmC levels compared to healthy MSCs. During HPC, global 5hmC levels were decreased while no appreciable changes occurred in histone H3 tri-methylation. ARAS MSCs cultured under HPC had higher migratory and proliferative capacity as well as increased vascular endothelial growth factor and epidermal growth factor expression compared to normoxia, and SA-β-gal activity decreased in both animal groups. Conclusions These data demonstrate that swine ARAS MSCs have decreased angiogenesis and increased senescence compared to healthy MSCs and that HPC mitigates MSC dysfunction, senescence, and DNA hydroxymethylation in ARAS MSC. Thus, HPC for MSCs may be considered for their optimization to improve autologous cell therapy in patients with nephropathies.