Atherosclerotic Artery Research Articles

Microvascular remodeling and altered angiogenic signaling in human kidneys distal to occlusive atherosclerotic renal artery stenosis.

Renal artery stenosis (RAS) is an important cause of chronic kidney disease and secondary hypertension. In animal models, renal ischemia leads to downregulation of growth factor expression and loss of intrarenal microcirculation. However, little is known about the sequelae of large-vessel occlusive disease on the microcirculation within human kidneys. This study included five patients who underwent nephrectomy due to renovascular occlusion and seven nonstenotic discarded donor kidneys (four deceased donors). Micro-computed tomography was performed to assess microvascular spatial densities and tortuosity, an index of microvascular immaturity. Renal protein expression, gene expression and histology were studied in vitro using immunoblotting, polymerase chain reaction and staining. RAS demonstrated a loss of medium-sized vessels (0.2-0.3 mm)comparedwithdonorkidneys (P=0.037) and increased microvascular tortuosity. RAS kidneys had greater protein expression of angiopoietin-1, hypoxia-inducible factor-1α and thrombospondin-1 but lower protein expression of vascular endothelial growth factor (VEGF) than donor kidneys. Renal fibrosis, loss of peritubular capillaries (PTCs) and pericyte detachment were greater in RAS, yet they had more newly formed PTCs than donor kidneys. Therefore, our study quantified significant microvascular remodeling in the poststenotic human kidney. RAS induced renal microvascular loss, vascular remodeling and fibrosis. Despite downregulated VEGF, stenotic kidneys upregulated compensatory angiogenic pathways related to angiopoietin-1. These observations underscore the nature of human RAS as a microvascular disease distal to main vessel stenosis and support therapeutic strategies directly targeting the poststenotic kidney microcirculation in patients with RAS.

Proteomic Characterization of Atherosclerotic Lesions In Situ Using Percutaneous Coronary Intervention Angioplasty Balloons—Brief Report

Materials extracted from atherosclerotic arteries can disclose data about the molecular pathology of cardiovascular disease, but obtaining such samples is complex and requires invasive surgery. To overcome this barrier, this study investigated whether angioplasty balloons inflated during standard percutaneous coronary interventions retain proteins from treated (dilated) atherosclerotic lesions and whether proteomic analysis of this material could provide data on lesion protein profiles and distinguish between patients with stable and unstable coronary artery disease. Patients with ST-segment-elevation myocardial infarction and stable angina pectoris were subjected to routine percutaneous coronary interventions. All angioplasty balloons inflated in a coronary artery were collected. Proteins retained on the balloons were extracted and analyzed using shotgun proteomic analysis. Proteomics identified and quantified 1365 unique proteins captured on percutaneous coronary intervention balloons. Control balloons inflated in the ascending aorta showed minimal nonspecific protein binding, indicating specificity to the luminal region of atherosclerotic lesions of the diseased artery wall. Clustering and principal component analyses showed that ST-segment-elevation myocardial infarction and stable angina pectoris subjects could be separated by variations in protein content and abundance. We identified 206 proteins as differentially abundant between ST-segment-elevation myocardial infarction and stable angina pectoris subjects. Pathway analysis indicated several enriched processes in the ST-segment-elevation myocardial infarction group involved in neutrophil-mediated immunity and platelet activation. Disease-related proteins from coronary artery lesions adhere to angioplasty balloons and constitute a source of material for proteomic analysis. This approach can identify proteins and processes occurring in unstable coronary atherosclerotic lesions and suggest novel therapeutic approaches.

Investigation of coronary artery tortuosity with atherosclerosis: A study on predicting plaque rupture and progression

This study investigated the effects of different patterns of coronary artery tortuosity (CAT) on the stress concentration of the plaques and the blood flow pattern inside an atherosclerotic artery to predict the risk of plaque rupture and progression. Four different loadings of the coronary artery, including pulsatile blood pressure as well as one-end twist around the artery axis at blood pressures of 74, 100, and 120 mmHg were considered. No study has addressed bent and twist buckling of an atherosclerotic artery considering pulsatile flow (for bent buckling), fluid-solid interaction, and different geometrical parameters of the plaque. The results showed that C-shape tortuosity under pulsatile blood pressure increased the maximum principal stress (MPS) by 10% to 58%, depending on plaque geometry. Application of one end twist, which led to tortuosity in the middle of the artery, increased MPS with rotation angle (e.g., an approximately 2-fold increase was observed for an internal pressure of 74 mmHg). At the moment of maximal transverse deformation, regions of low wall shear stress (WSS < 0.4 Pa) were formed after the tortuosity at the interior wall of the artery, making it prone to the formation of plaque. However, maximum WSS, which occurred at the stenotic region, will make the plaques more prone to rupture. The most influential parameters of plaque geometry on the amount of tortuosity, MPS, and WSS are the stenosis ratio, lipid core angle of 180°, plaque length, and fibrous cap thickness. Furthermore, the effect of mechanical properties of blood on WSS is studied.

Unsteady transport and two-phase binding of a drug in an atherosclerotic artery

To quantify the biology and physical understanding of endovascular drug delivery, a mathematical model that accounts for the two-phase binding of drug molecules in a diseased patient-specific artery has been developed. Using an image segmentation technique, the edges of the computational domain have been successfully extracted from an asymmetric intravascular ultrasound longitudinal image. The flow inside the porous tissue is described by the Brinkman model, and the luminal flow is Newtonian. At the lumen–tissue interface, an irreversible uptake kinetics for the injected drug from the luminal side into the tissue is taken into account. Furthermore, the drug's two-phase binding process, namely, the nonspecific binding caused by the drug's trapping in the extracellular medium (ECM-bound) and the specific binding caused by the interaction between drug molecules and receptors (REC-bound), has been considered. The Marker and Cell method has been leveraged to solve the governing equations numerically. Spatiotemporal variations of free drug, ECM-bound drug, and REC-bound drug are examined thoroughly for varying absorption parameter. Simulated results reveal that the interstitial flow amplifies drug distribution, retention, and delivery effectiveness, but flow separation downstream of the constriction reduces transmural flux. Concomitantly, the larger the absorption parameter, the higher the tissue content and effectiveness; nevertheless, significantly, larger absorption parameter values do not necessarily suggest improved delivery effectiveness. A thorough sensitivity analysis was carried out to predict the effects of some of the parameters involved.

Finite element analysis of the mechanical performance of a two-layer polymer composite stent structure

Bioresorbable stents (BRS) are an alternative to existing bare-metal stents (BMS) and drug-eluting stents (DES), aiming to reduce the short- and long-term complications in cardiovascular interventions. A combination of biodegradable polymers in a composite scaffold is a promising solution to improve BRS flexibility and strength, which is currently limited by the material properties of polymers. In this study, a mechanical performance of a composite BRS comprised of two layers with four different combinations of polylactic acid (PLA) and polycaprolactone (PCL) was examined with finite element analysis (FEA). Stent crimping and expansion with the balloon inside an atherosclerotic artery was simulated, and stent performance parameters were evaluated and compared between different composite layer configurations. The single-material PCL stent showed the highest recoil and failed to provide support to the artery, while the stiffer single-material PLA stent experienced significantly lower recoil, but also the highest dogboning during expansion, which could increase arterial wall damage. Nearly identical performance was observed for both mixed-material configurations, with recoil and foreshortening closer to single-material PLA stent and dogboning during expansion between both single-material stents. They showed the highest dogboning after balloon deflation due to a combination of permanent deformation at the ends of the stent and lower stiffness at the middle, which allowed for higher recoil at the middle but not at both ends of the stent. The combination of biodegradable polymers into composite BRS shows potential for targeted stent designs with performance tailored to specific needs.

The Maintained Glycemic Target Goal and Renal Function Are Associated with Cardiovascular and Renal Outcomes in Diabetic Patients Following Stent-Supported Angioplasty for Renovascular Atherosclerotic Disease.

Patients with type 2 diabetes mellitus (T2DM) constitute a large proportion of patients with atherosclerotic renal artery stenosis (ARAS). However, the mechanism of impaired renal function and hypertension in this subset of patients is multifactorial. We aimed to investigate whether, in diabetic patients, renal function (RF), systolic (SBP) and diastolic blood pressure (DBP) values following stent-supported angioplasty (PTA) for ARAS have an impact on cardiovascular and renal outcomes. Methods: The study group included 93 patients with T2DM and resistant hypertension who underwent PTA for ARAS. The pre- and post-procedure (6 to 12, and 24 months) values of SBP, DBP, eGFR and glycaemia were obtained. The prospective follow-up of median 44 months was performed for combined outcome: major cardiac and cerebral events (MACCE) and progression to renal replacement therapy (RRT). Results: MACCE-RRT occurred in 46 (49.5%) patients, with higher incidence in patients with higher values of SBP (147.8 ± 25.8 vs. 136.7 ± 15.8 mmHg, p = 0.006), DBP (80.8 ± 13.3 vs. 74.4 ± 12.3 mmHg, p = 0.009), chronic kidney disease in stages 3B to 5 (p = 0.029) and those who have not obtained target glycemic goals compared to well-maintained T2DM (p = 0.007) at 24-months. On multivariate Cox analysis, well-maintained T2DM targets [Hazard Ratio (HR):0.27; 95% Confidence Interval (CI):0.13–0.57; p < 0.001], eGFR below 45 mL/min/m2 (HR: 2.20; 95%CI: 1.20–4.04; p = 0.011), previous stroke (HR:2.52; 95%CI:1.19–5.34; p = 0.015) retained their associations with MACCE-RRT, while BP values were not associated with the outcome. Conclusions: The post-procedural RF, maintained glycemic target goal and previous stroke are vital for the outcome in patients undergoing PTA for renovascular disease in diabetic patients.

Circulating Biomarkers Predict Symptomatic but Not Asymptomatic Carotid Artery Stenosis

Background: Subjects exposed to risk factors such as age, gender, hypertension, diabetes mellitus, and smoking are prone to atherosclerotic events. Aims: The main aim of this longitudinal cohort study was to determine whether the role of novel plasma biomarkers for atherosclerotic carotid artery disease is different in subjects developing symptomatic carotid artery stenosis (CAS), as opposed to those with incident asymptomatic CAS. Methods: The following biomarkers were measured in 5,550 middle-aged subjects in a population-based cohort study: C-reactive protein (CRP), lipoprotein-associated phospholipase A2 mass and activity, proneurotensin, midregional proadrenomedullin (MR-proADM), midregional proatrial natriuretic peptide (MR-proANP), N-terminal pro-B-type natriuretic peptide (NT pro-BNP), copeptin, and cystatin C. After exclusion of those with prevalent CAS, subjects were thereafter followed in national patient registers for 23.4 (interquartile range 19.5–24.3) years regarding incident symptomatic and asymptomatic CAS. Results: Among 110 patients with confirmed incident CAS, 56 were symptomatic and 54 were asymptomatic. When including conventional risk markers in a Cox regression analysis, NT pro-BNP (hazard ratio [HR] 1.59; 95% confidence interval [CI]: 1.20–2.11), MR-proADM (HR 1.40; CI: 1.13–1.73), cystatin C (HR 1.21; CI: 1.02–1.43), and CRP (HR 1.53; CI: 1.13–1.73) were independently associated with incident symptomatic CAS, whereas no plasma biomarker was associated with incident asymptomatic CAS. Conclusion: Plasma biomarkers NT pro-BNP, MR-proADM, cystatin C, and CRP were independently associated with incident symptomatic CAS, whereas no such association could be demonstrated with incident asymptomatic CAS. As these biomarkers indicate future development of clinically relevant atherosclerotic CAS, their potential utility in relation to intensified preventive measures and selection of potential candidates for carotid surgery should be further evaluated.

Функциональные особенности зрительного анализатора у пациентов с хронической ишемической нейрооптикопатией, ассоциированной с гемодинамически значимым атеросклеротическим стенозом внутренней сонной артерии, после проведенной каротидной эндартерэктомии

Purpose. To evaluate effect of carotid endarterectomy (CE) in long-term follow-up period on course of chronic ischemic optic neuropathy (CION) associated with hemodynamically significant atherosclerotic internal carotid artery (ICA) stenosis. Material and methods. The object of study was 30 patients (30 eyes) with CION associated with hemodynamically significant atherosclerotic ICA stenosis. All patients underwent study of visual evoked potential (VEP), optical coherence tomography, Doppler ultrasonography of ophthalmic artery (OA) before and after ICA CE. Results. By the end of observation period (12 months), in patients with CION, despite the improvement blood flow in OA, there was deterioration in VEP and decrease in the thickness of the peripapillary retinal nerve fiber layer, the cause of which can be considered imbalance of energy metabolism that negatively affects the ganglion cells axons, leading to their death. Conclusion. Our studies show that further studies are needed to study the effect of ICA CE on the course of CION. Keywords: chronic ischemic optic neuropathy, ocular ischemic syndrome, hemodynamically significant internal carotid artery stenosis, visual evoked potential, optical coherence tomography.

Prevalence and Prognostic Impact of Carotid Artery Disease in Patients Undergoing Transcatheter Aortic Valve Implantation

To assess the prevalence of atherosclerotic carotid artery disease (ACAD) in patients undergoing transcatheter aortic valve implantation (TAVI) and postoperative cerebrovascular accidents (CVAs) and evaluate its prognostic impact on postoperative CVAs. A retrospective review of all consecutive patients with severe symptomatic aortic valve stenosis (AVS) who underwent TAVI was conducted at a single tertiary university hospital (January 2008-December 2018). Patients with AVS scheduled for TAVI and concomitant carotid stenosis were evaluated for prophylactic carotid revascularization (carotid endarterectomy [CEA] or carotid artery stenting [CAS]). Seven hundred and seventy one consecutive patients (mean age: 80 years, 52% males) were treated by TAVI procedures. Carotid stenosis > 70% was detected in 69 patients (9%); it was unilateral in 47 (68%) and bilateral in 22 (32%) patients. Prophylactic carotid revascularization was performed before TAVI in 45 patients (31%): in 63.1% of patients (30/47) with unilateral carotid stenosis > 70% and in 68.1% (15/22) with bilateral carotid stenosis > 70%. Postoperative CVA following TAVI procedures were recorded in 25 patients (3.2%): 22 cases of stroke (2.8%) and 3 cases of transient ischemic attack (0.4%). At a multiple logistic regression, only bilateral carotid stenosis > 70% (odds ratio [OR] 1.16, confidence interval [CI] 95% 1.03-1.31; P = 0.0009) was found as independent predictors of periprocedural CVA. In patients with severe symptomatic AVS undergoing TAVI, carotid stenosis was frequently observed. Unilateral carotid stenosis > 70% did not show a significant association with early CVA following TAVI. However, in the cohort of patients with bilateral carotid stenosis > 70%, a significant association with postoperative CVA was observed.

Renal Artery Stenting in Consecutive High-Risk Patients With Atherosclerotic Renovascular Disease: A Prospective 2-Center Cohort Study.

BackgroundThe aim of this study was to prospectively evaluate the effects of renal artery stenting in consecutive patients with severe atherosclerotic renal artery stenosis and high‐risk clinical presentations as defined in a national protocol developed in 2015.Methods and ResultsSince the protocol was initiated, 102 patients have been referred for revascularization according to the following high‐risk criteria: severe renal artery stenosis (≥70%) with true resistant hypertension, rapidly declining kidney function, or recurrent heart failure/sudden pulmonary edema. At baseline, the mean 24‐hour ambulatory systolic blood pressure was 166.2 mm Hg (95% CI, 162.0–170.4), the defined daily dose of antihypertensive medication was 6.5 (95% CI, 5.8–7.3), and the estimated glomerular filtration rate was 41.1 mL/min per 1.73m2 (95% CI, 36.6–45.6). In 96 patients with available 3‐month follow‐up data, mean 24‐hour ambulatory systolic blood pressure decreased by 19.6 mm Hg (95% CI, 15.4–23.8; P<0.001), the defined daily dose of antihypertensive medication was reduced by 52% (95% CI, 41%–62%; P<0.001), and estimated glomerular filtration rate increased by 7.8 mL/min per 1.73m2 (95% CI, 4.5–11.1; P<0.001). All changes persisted after 24 month follow‐up. Among 17 patients with a history of hospitalization for acute decompensated heart failure, 14 patients had no new episodes after successful revascularization.ConclusionsIn this prospective cohort study, we observed a reduction in blood pressure and antihypertensive medication, an increase in estimated glomerular filtration rate, and a decrease in new hospital admissions attributable to heart failure/sudden pulmonary edema after renal artery stenting.RegistrationURL: https://clinicaltrials.gov. Identifier: NCT02770066.

Embedded 3D Printing of Ultrasound‐Compatible Arterial Phantoms with Biomimetic Elasticity

AbstractHere, a class of ink materials and an embedded 3D printing strategy for the fabrication of macroscale elastic tissue‐mimetic constructs are presented. Novel inks composed of 10 wt% glycidyl methacrylated poly(vinyl alcohol) (PVAGMA) with different degrees of substitution (DOS) and 4 wt% cellulose nanocrystals (CNCs) (PVAGMA(DOS)/CNC) with strong shear‐thinning property are developed. By controlling the DOS of PVAGMA, hydrogels with desired mechanical stiffness mimicking that of healthy and diseased artery are designed to construct vascular phantoms. Cyclic tensile tests and in vitro hemodynamic study performed on phantoms demonstrate their excellent mechanical stability and low hysteresis. The burst pressure is found to be about 273 mmHg for PVAGMA2/CNC and 102 mmHg for PVAGMA4/CNC and the printed vascular phantoms are able to withstand 863K cycles over 10 days. Further, their suitability for ultrasonic imaging is demonstrated. Via B‐mode imaging, it is found that the vessel strains under a pulsatile flow are 11.7 ± 1.0% and 6.5 ± 1.5% for PVAGMA2/CNC and PVAGMA4/CNC vessels, respectively, perfectly matching the behaviors of healthy and atherosclerotic arteries. It exemplifies that the ink materials and printing strategy can have broad applications in biomedical research, especially for the fabrication of complex elastic tissue phantoms.

Blood Oxygen Level Dependent Magnetic Resonance Imaging To Predict Split Renal Function Improvement After Renal Artery Stenting

Atherosclerotic renal artery stenosis (ARAS) is the most common cause of secondary hypertension.1 Renal artery stenting (RAS) is the first line revascularisation option with a high technical success rate, but the clinical response rate is indeterminate.2 Blood oxygen level dependent magnetic resonance imaging (BOLD-MRI) is a non-invasive imaging technique that can assess the kidney’s oxygenation.3 It uses endogenous deoxygenated haemoglobin as a contrast agent and detects magnetic field disturbances caused by changes of oxygenated haemoglobin.

Impact of Percutaneous Transluminal Renal Angioplasty on Autonomic Nervous System and Natriuresis in Hypertensive Patients With Renal Artery Stenosis.

BackgroundWe investigated the early postoperative effect of percutaneous transluminal renal angioplasty on ambulatory blood pressure (BP) and the circadian characteristics of natriuresis and autonomic nerve activity.Methods and ResultsA total of 64 patients with hypertension with hemodynamically significant renal artery stenosis (mean age, 60.0±21.0 years; 31.3% fibromuscular dysplasia) who underwent angioplasty were included, and circadian characteristics of natriuresis as well as heart rate variability indices, including 24‐hour BP, low‐frequency and high‐frequency (HF) components, and the percentage of differences between adjacent normal R‐R intervals >50 ms were evaluated using an oscillometric device, TM‐2425, both at baseline and 3 days after angioplasty. In both the fibromuscular dysplasia and atherosclerotic stenosis groups, 24‐hour systolic BP (fibromuscular dysplasia, −19±14; atherosclerotic renal artery stenosis, −11±9 mm Hg), percentage of differences between adjacent normal R‐R intervals >50 ms, HF, brain natriuretic peptide, and nighttime urinary sodium excretion decreased (all P<0.01), and heart rate increased (both P<0.05) after angioplasty. In both groups, revascularization increased the night/day ratios of percentage of differences between adjacent normal R‐R intervals >50 ms (both P<0.01) and HF, and decreased those of low frequency/HF (all P<0.05) and nighttime urinary sodium excretion (fibromuscular dysplasia, 1.17±0.15 to 0.78±0.09; atherosclerotic renal artery stenosis, 1.37±0.10 to 0.99±0.06, both P<0.01). Multiple logistic regression analysis indicated that a 1‐SD increase in baseline low frequency/HF was associated with at least a 15% decrease in 24‐hour systolic BP after angioplasty (odds ratio, 2.30 [95% CI, 1.03–5.67]; P<0.05).ConclusionsSuccessful revascularization results in a significant BP decrease in the early postoperative period. Intrarenal perfusion might be a key modulator of the circadian patterns of autonomic nerve activity and natriuresis, and pretreatment heart rate variability evaluation seems to be important for treatment success.

Treatment of Atherosclerotic Femoropopliteal Artery Disease with Supera Interwoven Nitinol Stent: A Real-World Study in China

To analyze the outcomes of Supera stent deployment in Chinese patients with atherosclerotic femoropopliteal artery (FPA) disease in a real-world setting. This retrospective cohort study collected and analyzed the medical records of 246 consecutive patients who received Supera stents for FPA disease at the China Academy of Chinese Medical Sciences Xiyuan Hospital between February 2017 and December 2019. All study patients underwent balloon angioplasty and were treated with Supera stents (Abbott Vascular, Santa Clara, CA, USA). The primary outcome was the rate of primary patency 12months after discharge. The analyses included 246 consecutive patients and 260 lesions. The mean±SD age was 73.2±9.9years and most patients (60.2%) were males. Of the 260 treated lesions, Supera stents were deployed in eight (3.1%) cases after a previous stent fracture. Critical limb ischemia was diagnosed in 87.3% of the limbs, and 84 (32.3%) and 83 (31.5%) cases were classified as TransAtlantic Inter-Society Consensus (TASC) C and D, respectively. Most of the lesions were in situ (80.8%) and located in the superficial femoral artery (45.0%) or the FPA (45.8%). The mean lesion length was 147.7mm. Nominal deployment (-10 to 10% compression) was the most common deployment scenario (84.1%). The 1-year primary patency rate was 80.6%. Lesions that occurred as restenosis (odds ratio [OR]:=3.34, 95% confidence interval [CI]: 1.03-10.85, P=0.045) or in-stent restenosis (OR:=2.88, 95% CI: 1.03-8.07, P=0.045) were independently associated with occlusion or stenosis after stent deployment. No stent fracture was observed in this study. Our study indicates that the use of Supera stents is feasible for the treatment of Chinese patients with FPA disease. The long-term results reveal high primary patency.

Exaggerated natriuresis after renal artery balloon angioplasty for flash pulmonary oedema: a potential complication in one-kidney renovascular hypertension.

Flash pulmonary oedema is a life-threatening complication of renal artery stenosis. We report a very rare complication in a patient with bilateral atherosclerotic renal artery stenosis who underwent unilateral renal artery angioplasty because of recurrent flash pulmonary oedema. Shortly after the procedure, she developed extreme polyuria (over 201 in the first 48 h) with massive natriuresis (>1000 mmol urinary sodium excretion in the first 24 h). Most likely, the occurrence of this phenomenon is related to the fact that her contralateral kidney was atrophic and no longer functioning due to total renal artery occlusion. We provide an overview of the literature and discuss several mechanisms that may contribute to the occurrence of this exaggerated natriuretic response in patients with one-kidney renovascular hypertension who undergo renovascular revascularization. We recommend close monitoring of natriuresis in such patients and - if needed - administration of intravenous isotonic saline (0.9% NaCl) to prevent hypovolemia.

Anti-inflammatory strategies for atherosclerotic artery disease

ABSTRACT Introduction Atherosclerosis is the most frequent cause of coronary artery disease (CAD) and inflammation is a key driver of its pathogenesis. Targeting inflammation represents a novel therapeutic option beyond management of conventional cardiovascular risk factors. Recent efforts in cardiovascular research were aimed at investigating the efficacy and safety of existing and novel anti-inflammatory drugs. Areas covered The multimodal activation of the immune response enables several approaches to mitigate the inflammatory burden of atherosclerosis, which include general cardiovascular preventive measures from healthy lifestyle behaviors to medications with ancillary anti-inflammatory effects, such as lipid-lowering drugs. Clinical development of several specific anti-inflammatory drugs has been halted due to lack of proven efficacy in humans, while a number of trials are ongoing to test drugs targeting the NLRP3-IL1-IL6-hsCRP pathway, including drugs that are already in use for immune disorders (i.e. colchicine). Expert opinion The main challenge associated with specific anti-inflammatory drugs is the risk of immunological suppression. Due to positive results in recent randomized trials and a favorable safety profile, colchicine is expected to gain more popularity in the near future as an anti-inflammatory agent for cardiovascular prevention.

1-Year Outcomes of Fluoropolymer-Based Drug-Eluting Stent in Femoropopliteal Practice: Predictors of Restenosis and Aneurysmal Degeneration.

This study aimed to investigate the 1-year risk of restenosis and aneurysmal degeneration and explore the associated factors after femoropopliteal implantation of fluoropolymer-based drug-eluting stents (FP-DESs) for symptomatic atherosclerotic peripheral artery disease in real-world practice. Although clinical trials have demonstrated that FP-DES implantation has favorable 1-year outcomes, its performance in real-world practice has not been well elucidated. This multicenter, prospective, observational study evaluated 1,204 limbs (chronic limb-threatening ischemia: 34.8%, mean lesion length: 18.6 ± 9.9cm, chronic total occlusion: 53.2%, bilateral wall calcification: 41.9%) of 1,097 patients with peripheral artery disease (age: 75 ± 9 years, men: 69.4%, diabetes mellitus: 60.8%, chronic kidney disease: 66.2%) undergoing Eluvia (Boston Scientific) drug-eluting stent implantation for femoropopliteal lesions. The primary outcome measure was 1-year restenosis, whereas the secondary outcome measures were 1-year occlusive restenosis, stent thrombosis, target lesion revascularization, and aneurysmal degeneration. The 1-year occurrence rates of restenosis (12.9%), occlusive restenosis (9.2%), stent thrombosis (3.3%), target lesion revascularization (6.2%), and aneurysmal degeneration (16.8%) were found. Multivariate analysis demonstrated that dialysis, chronic limb-threatening ischemia, history of revascularization, a smaller reference vessel diameter, chronic total occlusion, and spot stenting were significantly associated with an increased risk of 1-year restenosis, whereas intravascular ultrasound use and subintimal wire passage were significantly associated with an increased risk of 1-year aneurysmal degeneration. This study documented the 1-year clinical outcomes after femoropopliteal endovascular therapy with FP-DES implantation in real-world practice. The 1-year restenosis rate would be clinically acceptable, whereas the occurrence of occlusive restenosis and aneurysmal degeneration should be noted.

Prediction of Split Renal Function Improvement After Renal Artery Stenting by Blood Oxygen Level-Dependent Magnetic Resonance Imaging.

BackgroundThe discrepancy between the high technical success rate and the relatively low clinical response rate of renal artery stenting (RAS) raises the importance to identify atherosclerotic renal artery stenosis (ARAS) patients who are most likely to benefit from RAS. This study aimed to investigate the feasibility and accuracy of blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI) in predicting split renal function (SRF) improvement after RAS in patients with ARAS.MethodsThirty patients with severe ARAS who were treated with RAS were enrolled. Baseline cortical and medullary R2* values of each kidney were measured by BOLD-MRI, and each patient’s SRF was evaluated by nuclear renal dynamic imaging at baseline and 1-month follow-up.ResultsIn total, 35 severe stenotic renal arteries of the 30 patients were analyzed. At 1-month follow-up, 34 kidneys (97.1%) of severe ARAS had acquired SRF. SRF improved in 12 kidneys of 10 patients. The cortical R2* and medullary R2* values in the SRF improvement kidneys were higher than those in the non-improvement kidneys (P ≤ 0.001). The area under the curve of medullary R2* was 0.879 (95% confidence interval [CI] 0.736–1.000). A medullary R2* value ≥29.1 s–1 was noted to provide good sensitivity (0.833, 95% CI 0.552–0.970) and specificity (0.864, 95% CI 0.667–0.953) in predicting SRF improvement. Medullary R2* value was the only independent predictor of SRF improvement in multivariable analysis (P = 0.034, OR 3.017, 95%CI 1.089–8.358).ConclusionThis study showed that a BOLD-MRI medullary R2* value ≥29.1 s–1 was an excellent predictor of SRF improvement in patients with severe ARAS who underwent renal artery stenting.

Interaction between bacteria and cholesterol crystals: Implications for endocarditis and atherosclerosis.

BackgroundThe interaction between pathogenic bacteria and cholesterol crystals (CCs) has not been investigated. However, CCs are found extensively in atherosclerotic plaques and sclerotic cardiac valves. Interactions between pathogenic bacteria and CCs could provide insights into destabilization of atherosclerotic plaques and bacterial adhesion to cardiac valves.MethodsStaphylococcus aureus and Pseudomonas aeruginosa were used to assess in vitro bacterial adhesion to CCs and proliferation in the presence of CCs compared to plastic microspheres and glass shards as controls. Ex vivo studies evaluated bacterial adhesion to atherosclerotic rabbit arteries compared to normal arteries and human atherosclerotic carotid plaques compared to normal carotid arteries. Scanning electron microscopy (SEM) was used to visualize bacterial adhesion to CCs and confocal microscopy was used to detect cholesterol binding to bacteria grown in the presence or absence of CCs.ResultsIn vitro, S. aureus and P. aeruginosa displayed significantly greater adhesion, 36% (p<0.0001) and 89% (p<0.0001), respectively, and growth upon exposure to CCs compared to microspheres or glass shards. Rabbit and human atherosclerotic arteries contained significantly greater bacterial burdens compared to controls (4× (p<0.0004); 3× (p<0.019), respectively. SEM demonstrated that bacteria adhered and appeared to degrade CCs. Consistent with this, confocal microscopy indicated increased cholesterol bound to the bacterial cells.ConclusionsThis study is the first to demonstrate an interaction between bacteria and CCs showing that bacteria dissolve and bind to CCs. This interaction helps to elucidate adhesion of bacteria to sclerotic valves and atherosclerotic plaques that may contribute to endocarditis and plaque destabilization.

Review of Renal Artery Stenosis and Hypertension: Diagnosis, Management, and Recent Randomized Control Trials.

Renal artery stenosis is one of the most common causes of secondary hypertension (HTN). Renal artery stenosis-induced HTN can occur in the presence of unilateral or bilateral narrowing and a solitary kidney with stenotic artery, which may subsequently lead to renal insufficiency (e.g., ischemic kidney disease) or pulmonary edema. Renal artery stenosis can be diagnosed using multiple modalities, including Doppler ultrasound, computed tomography angiography, magnetic resonance angiography, or selective angiogram. Although atherosclerotic renal artery stenosis management in patients with HTN has been greatly controversial, it is inevitable in the treatment of some selected cases. These cases can be treated by either percutaneous angioplasty (with or without stenting) or less common, open surgical approach revascularization, both of which have excellent primary patency rates. Generally, several trials on renal artery angioplasty or stenting in patients with atherosclerotic disease have shown that the long-term benefits in terms of blood pressure control and renal function over pharmacological management is not substantial. Furthermore, studies could not demonstrate a prolongation of event-free survival after renal vascularization. Moreover, endovascular procedures have substantial risks. Careful patient selection is required when considering revascularization, for including those with refractory HTN or progressive renal failure, to maximize the potential benefits. This paper discusses the epidemiology of atherosclerotic renal artery stenosis and its clinical presentation, diagnosis, treatment, prognosis, and future perspectives.