Brachial Artery Research Articles

ESR Essentials: arterial vascular access and closure devices-practice recommendations by the Cardiovascular and Interventional Radiological Society of Europe.

Vascular access is the initial, very important, step of endovascular procedures. Various access sites include the common femoral artery, brachial artery, radial artery, popliteal artery, and distal tibial vessels (pedal arteries). Successful arterial access requires advanced knowledge of anatomy, as well as proper training and experience. Today, vascular access should be obtained using real-time, ultrasound guidance to reduce access time, patient discomfort, and puncture-related complications including dissection, arteriovenous communication, and bleeding. Nevertheless, high-level evidence to support this recommendation in peripheral procedures is limited and level A data are mainly derived from randomized cardiac trials investigating only radial and femoral access. Vascular closure devices (VCDs) for femoral access can be broadly categorized as active closure devices, compression assist devices, and external/topical hemostasis devices. There is high-level evidence demonstrating that their use is related to less time for ambulation and increased patient satisfaction. However, available data failed to clearly demonstrate a benefit in complications compared to standard manual compression in peripheral endovascular arterial procedures, and thrombotic and infectious complications reported following VCD use remain an issue. Heterogeneity noted in the literature, caused by the vast variety of devices, access sites, sheath sizes, clinical scenarios, and procedures, poses difficulties in data analysis and future study design. As a result, an individualized VCD use is currently suggested for ≥ 5 Fr femoral artery access not only to reduce time to hemostasis and ambulation and to improve patient comfort, but also to reduce bleeding complications in cases of femoral access with increased bleeding risk, deranged coagulation, and large-bore access, though a high level of evidence to support this later recommendation is limited. KEY POINTS: US guidance is strongly recommended for femoral access and is mandatory to obtain more challenging access. The use of VCDs for femoral hemostasis is generally safe, effective, and currently supported by level I evidence. Proper training and correct VCD choice, based on the patient's individual characteristics, are imperative to optimize outcomes.

Vascular endothelial function and its response to moderate-intensity aerobic exercise in trained and untrained healthy young men

30 min of moderate-intensity aerobic exercise per day is recommended, but the response and adaptation of endothelial function (EF) to this exercise remains controversial. The purpose of this study was to determine the changes in EF in endurance trained and untrained individuals before and after this exercise and to compare the differences between trained and untrained individuals. Twelve endurance-trained male college athletes (trained group) and 12 untrained male college students (untrained group) performed a 30-min run at an intensity of 60% VO2max. Brachial artery flow-mediated dilation (FMD) was measured before exercise, 30 min and 60 min after exercise, and the following morning. Resting diameter and maximum diameter showed large time effects (p < 0.001, η2 = 0.533; p < 0.001, η2 = 0.502). Resting diameters at 30 and 60 min after exercise were higher than before exercise in both the untrained and trained groups (p < 0.05), and maximum diameters at 30 min after exercise were higher than before exercise in both the untrained and trained groups (p < 0.01). Resting diameter and maximum diameter also exhibited some group effects (p = 0.055, η2 = 0.157; p = 0.041, η2 = 0.176). Resting diameters and maximum diameters were higher in the trained group than in the untrained group before exercise (p < 0.05). FMD (%) showed no time, group, or time-group interaction effects. 30 min of moderate-intensity aerobic exercise can increase resting and maximal arterial diameters in both trained and untrained young men, but has no effect on FMD. Long-term endurance training has the potential to increase resting and maximal arterial diameters in young men, but not necessarily FMD.

Establishing an autogenous vascular access program in a Guatemalan comprehensive pediatric nephrology center.

The Guatemalan Foundation for Children with Kidney Diseases collaborated with Bridge of Life, a not-for-profit charitable organization, to establish a vascular access program. We reviewed our experience with graded surgical responsibility and structured didactic training, creating arteriovenous fistulas (AVF) for Guatemalan children. Pediatric vascular access missions were completed from 2015 to 2023 and analyzed retrospectively. Follow-up was completed by the Guatemalan pediatric surgeons, nephrologists, and nursing staff. AVF patency and patient survival were evaluated by Kaplan-Meier life-table analysis with univariate and multivariable association between patient demographic variables by Cox proportional hazards models. Among a total of 153 vascular access operations, there were 139 new patient procedures, forming the study group for this review. The mean age was 13.6years, 42.6% were female, and the mean BMI was 17.3. Radial or ulnar artery-based direct AVFs were established in 100 patients (71.9%) and ten of the 25 transposition procedures. Brachial artery inflow was required in 29 direct AVFs (20.9%). Two patients underwent femoral vein transpositions. Access-related distal ischemia was not encountered. Seven of the AVF patients later required access banding for arm edema; all had previous dialysis catheters (mean = 9, range 4-12). Primary and cumulative patency rates were 84% and 86% at 12months and 64% and 81% at 24months, respectively. The median follow-up was 12months. Overall patient survival was 84% and 67% at 12 and 24months, respectively. There were no deaths related to AVF access. Safe and functional AVFs were established in a teaching environment within a Guatemalan comprehensive pediatric nephrology center.

Abstract MP27: Pregnant Women of Advanced Maternal Age Have Higher Central Artery Stiffness Than Younger Pregnant Women

The frequency of women undergoing pregnancy at advanced maternal age (AMA, ≥35 years) is increasing in developed countries, including the United States. AMA is associated with an increased risk of adverse pregnancy outcomes such as gestational hypertension, preeclampsia, and preterm birth. Increased risk for adverse pregnancy outcomes at AMA may be mediated in part by altered arterial structure and function or inadequate maternal arterial adaptations during pregnancy. Therefore, we examined central artery stiffness and endothelial function across healthy pregnancy (i.e. no comorbid maternal or fetal conditions, born at term) in women who had enrolled in a longitudinal study between March 2015 and January 2020. We hypothesized that women at AMA (age ≥35 years, mean±SE: 36±0 years, n=18) would have higher arterial stiffness and lower endothelial function compared with younger women (age 21-30 years, mean±SE: 27±0 years, n=51) across pregnancy. Hemodynamic and arterial function measures were collected in the first (6-13 weeks), second (18-26 weeks), and third (27-37 weeks) trimesters and postpartum (4-14 weeks after the delivery). Brachial artery blood pressure was assessed in the supine position and central artery stiffness was assessed via carotid-femoral (aortic) pulse wave velocity (cfPWV) and carotid β-stiffness index. Endothelial function was determined via brachial artery flow-mediated dilation (FMD). Brachial artery systolic, diastolic, and mean blood pressures were not different between AMA and younger women across pregnancy or postpartum (all P &gt;0.05). The AMA group had higher cfPWV ( P &lt;0.01) and carotid β-stiffness index ( P &lt;0.01) across pregnancy and postpartum compared to the younger group. cfPWV decreased among younger women at the second and third trimesters compared with the first trimester ( P &lt;0.01), while cfPWV among women of AMA did not change ( P =0.07). There were no differences in FMD between AMA and younger women across pregnancy or postpartum ( P =0.96). These results demonstrate that healthy women of AMA have increased central artery stiffness, but no difference in endothelial function, compared to younger pregnant women across pregnancy, and that the normal decrease in aortic stiffness is blunted in pregnant women of AMA compared to younger women. The sustained higher central artery stiffness throughout pregnancy among women of AMA may contribute to increased risk of pregnancy complications and future CVD risk in these women.

Trends in Venous Diameter and Brachial Artery Volume Flow of arteriovenous fistula in 12 Weeks Postoperatively

ObjectiveTo explore the trends of venous diameter and brachial artery volume flow (VF) in 12 weeks after arteriovenous fistula (AVF) and the influence of preoperative arterial diameter on this trend. Our goal was to clarify the maturation process within 12 weeks after AVF surgery. MethodsClinical data of 257 patients with end-stage renal disease who had their first radial-cephalic AVF established at our institution from February 1, 2023 to February 1, 2024 were included. The patients were divided into group A (radial artery diameter <1.5 mm), group B (radial artery diameter 1.5-2.0 mm), and group C (radial artery diameter >2.0 mm) according to the preoperative radial artery diameter. After AVF surgery, the artery and vein diameter, brachial artery VF were recorded at 1 day, 2 weeks, 4 weeks, 6 weeks, 8 weeks, 10 weeks and 12 weeks. Results1. The venous diameter and brachial artery VF of AVF showed an upward trend, and increased significantly in 1 day-6 weeks postoperatively (P < 0.05),especially between 1 day and 2 weeks, while no significant difference in the increases at 6-12 weeks. 2. Groups B and C were in line with the above trend, whereas the patients in group A showed best growth in 2-4 weeks postoperatively. 3. The natural maturation rates of AVF in groups B and C were significantly better than that of group A at all postoperative time (P＜0.05). ConclusionThe AVF was in a developmentally dominant stage at 6 weeks postoperatively, with 1 day-2 weeks being particularly prominent. The postoperative natural maturation rate of AVF with arteries diameter of<1.5 mm was low, the direct use of such arteries to establish AVFneed careful consideration.

Acute partial sleep restriction does not impact arterial function in young and healthy humans.

Habitual short sleep durations are associated with several cardiovascular diseases. Experimental research generally supports these findings as metrics of arterial function are impaired after complete deprivation of sleep and after longer periods of partial sleep restriction. The acute influence of a single instance of partial sleep restriction (PSR), however, has not been defined. We evaluated arterial structure and function among 32 university-aged participants on two occasions: once after normal habitual sleep (NS), and again the morning after an acute partial sleep restriction (PSR) intervention involving only 3h of sleep for a single night. Endothelial function was measured using ultrasonography at the brachial artery via flow-mediated dilatation (FMD), and a ramp peak oxygen uptake test was used to evaluate cardiorespiratory fitness. Blood samples were collected from a subset of participants to investigate the influence of circulatory factors on cellular mechanisms implicated in endothelial function. Sleep duration was lower after a night of PSR compared to NS (P<0.001); however, there were no appreciable differences in any haemodynamic outcome between conditions. FMD was not different between NS and PSR (NS: 6.5±2.9%; PSR: 6.3±2.9%; P=0.668), and cardiorespiratory fitness did not moderate the haemodynamic response to PSR (all P>0.05). Ex vivo cell culture results aligned with in vivo data, showing that acute PSR does not alter intracellular processes involved in endothelial function. No differences in arterial structure or function were observed between NS and acute PSR in healthy and young participants, and cardiorespiratory fitness does not modulate the arterial response to acute sleep restriction.

Abstract P223: Impact Of Dynamic Or Static Training On Flow-Mediated Dilatation Following Prolonged Head-Down Tilt Bedrest

Cardiovascular deconditioning, cephalad fluid shifts, and altered sympathetic activity in weightlessness may elicit changes in vascular structure and function akin to vascular ageing. Head-down tilt bedrest is an established terrestrial model for weightlessness and elicits similar cardiovascular responses. We hypothesized that 30 days head-down tilt bedrest (HDTBR) worsens flow mediated dilation (FMD), a non-invasive endothelial function marker, and that daily orthostatic stimuli or physical exercise attenuates the response. Fourty-seven healthy individuals (20 women, age 35±9 years, BMI 23.7±2.6 kg/m 2 ) were assigned to 30 days of strict HDTBR and divided into four groups: Daily 6 hours of upright sitting (positive control, n=11); 6 hours of -25 mmHg lower body negative pressure (n=12); 60 minutes of supine cycling followed by 6 hours of thigh cuff venous occlusion 6 days per week (n=12), or no countermeasure (negative control, n=12). We measured upper arm blood pressure and heart rate 5 days before and immediately after bedrest. We assessed plasma volume by carbon monoxide-rebreathing 2 days before and on day 28 of bedrest. We determined FMD of the brachial artery 5 days before, on day 28 of bedrest, and after 13-day recovery. We collected blood samples to measure pro- and anti-inflammatory cytokines. Heart rate was elevated after bedrest (p&lt;0.0001) but remained constant in seated and cycling groups (seated MD 5±2 /min, cycling MD 5±2, p=0.0051). Systolic blood pressure increased in all groups (MD 4±1 mmHg, p=0.0004). Diastolic blood pressure was higher post-bedrest in the control group (MD 8±2 mmHg, p=0.0002) but remained constant in the countermeasure groups. Plasma volume was reduced after bed rest (MD -400±37 ml, p&lt;0.0001) but maintained in the cycling group (MD 147±72 ml, p=0.0001). FMD did not differ between groups, but was higher at bedrest (MD 1.9±0.8 %, p=0.0481), whereas recovery values did not differ from baseline. Resting brachial artery diameter tended to be higher at bedrest (p=0.0876). Cytokines revealed no clinically relevant inflammatory response. Head-down tilt bedrest-induced cardiovascular deconditioning, which was not completely abolished by any countermeasure, paradoxically increased flow-mediated brachial vasodilation. Additional cardiovascular risk factors may be required to express endothelial dysfunction in the face of reduced physical activity.

Arteriovenous Shunts: Their Location and Role in Physiology, Pathology, and Tissue Transfer. A Preliminary Report in the Upper Limb.

Tiny arteriovenous (AV) shunts of 10-150 µm (0.01-0.15 mm) are documented in the hands and feet. Larger shunts up to 0.5 mm (500 µm) have been discovered by the authors in the inner canthus and the human eye. This study seeks their possible existence in the upper limb. Radiographic lead oxide cadaver injection and dissection studies of 14 archival and six new upper limbs were examined. AV shunts of 0.1-0.5 mm were discovered between the brachial, ulnar, and radial arteries and their venae comitantes and between their arterial perforators and the subcutaneous veins. This pilot study provides insight into the possible function of these large AV shunts associated with blood flow variation in temperature, blood pressure, tissue transfer, flap prefabrication, and flap necrosis.

Coronary and Systemic Vasodilator Responsiveness of Patients Receiving Conventional Intermittent or Nocturnal Hemodialysis.

Nocturnal hemodialysis (nHD) restores the attenuated brachial artery vasodilator responsiveness of patients receiving conventional intermittent hemodialysis (iHD). Its impact on coronary vasodilatation is unknown. We evaluated 25 patients on hemodialysis who fulfilled transplant criteria: 15 on iHD (4-hour sessions, 3 d/wk) and 10 on nHD (≈40 h/wk over 8-10-hour sessions) plus 6 control participants. Following diagnostic angiography, left anterior descending (LAD) coronary flow reserve and mean luminal diameter were quantified at baseline and during sequential intracoronary administration of adenosine (infusion and bolus), nitroglycerin (bolus), acetylcholine (infusion), acetylcholine coinfused with vitamin C, and, finally, sublingual nitroglycerin. Coronary flow reserve in those receiving nHD was augmented relative to iHD (3.28±0.26 versus 2.17±0.12 [mean±SEM]; P<0.03) but attenuated, relative to controls (4.80±0.63; P=0.011). Luminal dilatations induced by intracoronary adenosine and nitroglycerin were similar in nHD and controls but blunted in the iHD cohort (P<0.05 versus both). ACh elicited vasodilatation in controls but constriction in both dialysis groups (both P<0.05, versus control); vitamin C coinfusion had no effect. Sublingual nitroglycerin increased mid-left anterior descending diameter and reduced mean arterial pressure in controls (+15.2±2.68%; -16.00±1.60%) and in nHD recipients (+14.78±5.46%; -15.82±1.32%); iHD responses were markedly attenuated (+1.9±0.86%; -5.89±1.41%; P<0.05, all comparisons). Coronary and systemic vasodilator responsiveness to both adenosine and nitroglycerin is augmented in patients receiving nHD relative to those receiving iHD, whereas vasoconstrictor responsiveness to acetylcholine does not differ. By improving coronary conduit and microvascular function, nHD may reduce the cardiovascular risk of patients on dialysis.

No influence of steady-state postural changes on cerebrovascular compliance in humans.

The aim of this study was to determine the effect of posture changes on vascular compliance in intracranial (brain) versus extracranial vascular beds (forearm). Eighteen young adults (nine females) performed a supine-to-seated-to-standing protocol involving 5 min of rest in each position. Continuous blood pressure, middle cerebral artery (MCA) blood velocity, and brachial artery blood velocity were recorded at each posture. Three to five consecutive steady-state cardiac cycles at each posture were analyzed by a four-element lumped parameter modified Windkessel model to calculate vascular compliance. Mean arterial pressure (MAP) increased from supine to seated (76(9) vs. 81(12) mmHg; P=0.006) and from supine to standing (76(9) vs. 82(13) mmHg; P=0.034). Mean blood flow was greater in the MCA relative to the forearm (forearm: 40(5) mL·min-1, MCA: 224(17) mL·min-1; main effect P<0.001). Conversely, vascular resistance (forearm: 3.25(0.50) mmHg-1·mL·min-1, brain: 0.36(0.04) mmHg-1·mL·min-1; main effect P<0.001) and compliance (forearm: 0.010(0.001) mL·min-1·mmHg-1, brain: 0.005(0.001) mL·min-1·mmHg-1; main effect P=0.001) were greater in the forearm compared to the brain. Significant main effects of posture were observed with decreasing values in upright positions for mean blood flow (P=0.001) in both vascular beds, but not for resistance (P=0.163) or compliance (P=0.385). There were no significant interaction effects between vascular bed and posture for mean flow (P=0.057), resistance (P=0.258), or compliance (P=0.329). This study provides evidence that under steady-state conditions, posture does not affect cerebrovascular compliance.

Abstract 14: Arterial Stiffness in Obese Normotensive Children: The First Cardiovascular Risk Biomarker?

Introduction: Obesity is an emerging pandemic driven by consumption of a diet rich in fat, highly refined carbohydrates and a sedentary lifestyle in both children and adults. In obesity arterial stiffness (AS) often associated with endotelial dysfunction (ED) is an independent and strong predictor of cardiovascular disease (CVD) and is a precursor to atherosclerosis, systolic hypertension, cardiac diastolic dysfunction, and impairment of coronary and cerebral flow. In obese children, AS also promotes fatty liver disease whitch eventually leads to fibrosis. Aim of Study: In obese children (OC), central blood pressuere, arterial stiffness and endothelial dysfunction, liver steatosis/fibrosis were evaluated and compared with control group (CG), non-obese, non-hypertensive children. Methods: Carotid-femoral pulse wave velocity (PWV) is the current non-invasive method of choice to asses AS and PWV carotid-brachial variation pre- and post-induced transient ischemia of brachial artery to evaluate ED. Fibroscan (FS) and Control Attenuation Parameter (CAP) are a non-invasive reliable examination that allows to know the degree of liver steatosis and liver stiffness (fibrosis). Carotid-femoral PWV (AS) and PWV variation of brachial artery (ED) were assessed using Complior System® (Artech-Medical France). We evaluated 31 obese children between 10 and 13 years old (BMI 28.70±3.72) and compared to CG (between 11 and 13 years old, n=16, BMI 19.89±1.75) Results: In obese children (BMI 28.70±3.72 and Z score 2.02±0.42) vs CG (BMI 19.89±0.75 and Z core 0.57±0.24), PWV-CF (arterial stiffness) was significantly increased: 5.8±1.3 m/s vs. 3.4±0.9 m/s, p&lt;0.01. PWV-CB variation were paradogical (endothelial dysfunction) after transient ischemia in obese children (△+9% compared to baseline) and it was as epected in the CG (△-12.2% compared to baseline) (P&lt;0.001). Fibroscan and CAP revealed that the degree of steatosis was significantly higher in OC but no differences were found in the degree of liver fibrosis. Conclusions: We found a significatly increase in arterial stiffness in obese children compared to CG. Arterial stiffness in obese children often precedes the development of hypertension and liver fibrosis (even in the presence of liver steatosis) suggesting that arterial stiffness is one of the earliest biomarkers for increased cardiovascular risk. Interventions aimed at attenuating obesity in chidhood are emerging as important target to improve public health outcomes.

Assessment of Brachial Artery Dimensions and Variations: A Comprehensive Study

Assessment of Brachial Artery Dimensions and Variations: A Comprehensive Study

Endothelial Dysfunction in Youth-Onset Type 2 Diabetes: A Clinical Translational Study.

Youth-onset type 2 diabetes (Y-T2D) is associated with increased risk for coronary atherosclerotic disease, but the timing of the earliest pathological features and evidence of cardiac endothelial dysfunction have not been evaluated in this population. Endothelial function magnetic resonance imaging may detect early and direct endothelial dysfunction in the absence of classical risk factors (severe hyperglycemia, hypertension, and hyperlipidemia). Using endothelial function magnetic resonance imaging, we evaluated peripheral and coronary artery structure and endothelial function in young adults with Y-T2D diagnosed ≤5 years compared with age-matched healthy peers. We isolated and characterized plasma-derived small extracellular vesicles and evaluated their effects on inflammatory and signaling biomarkers in healthy human coronary artery endothelial cells to validate the imaging findings. Right coronary wall thickness, coronary artery flow-mediated dilation, and brachial artery flow-mediated dilation were measured at baseline and during isometric handgrip exercise using a 3.0T magnetic resonance imaging. Human coronary artery endothelial cells were treated with Y-T2D plasma-derived small extracellular vesicles. Protein expression was measured by Western blot analysis, oxidative stress was measured using the redox-sensitive probe dihydroethidium, and nitric oxide levels were measured by 4-amino-5-methylamino-2',7'-difluororescein diacetate. Y-T2D (n=20) had higher hemoglobin A1c and high-sensitivity C-reactive protein, but similar total and LDL (low-density lipoprotein)-cholesterol compared with healthy peers (n=16). Y-T2D had greater coronary wall thickness (1.33±0.13 versus 1.22±0.13 mm; P=0.04) and impaired endothelial function: lower coronary artery flow-mediated dilation (-3.1±15.5 versus 15.9±17.3%; P<0.01) and brachial artery flow-mediated dilation (6.7±14.7 versus 26.4±15.2%; P=0.001). Y-T2D plasma-derived small extracellular vesicles reduced phosphorylated endothelial nitric oxide synthase expression and nitric oxide levels, increased reactive oxygen species production, and elevated ICAM (intercellular adhesion molecule)-mediated inflammatory pathways in human coronary artery endothelial cells. Coronary and brachial endothelial dysfunction was evident in Y-T2D who were within 5 years of diagnosis and did not have severe hyperglycemia or dyslipidemia. Plasma-derived small extracellular vesicles induced markers of endothelial dysfunction, which corroborated accelerated subclinical coronary atherosclerosis as an early feature in Y-T2D. URL: https://www.clinicaltrials.gov; Unique identifier: NCT02830308 and NCT01399385.

Challenging the Controversy Surrounding Percutaneous Brachial Artery Access Related Complications: A Systematic Review and Meta-Analysis.

Endovascular therapy has become increasingly preferred in the diagnosis and treatment of various conditions. The choice of arterial access usually depends on the type of procedure being performed with most via the common femoral artery and increasingly via the radial artery. Percutaneous access via the brachial artery has however been approached with caution due to the perceived increased risk for development of complications. Percutaneous brachial artery access (pBAA) has insufficient evidence when compared to femoral and radial access, with no large-scale studies available. The objective of this study is to review the literature and report the clinical and radiological complications associated with pBAA. EMBASE, EMCARE, CINAHL and Medline were searched for existing data on the complications associated with pBAA. Systematic review and meta-analysis were carried out on the data of 31 studies. The results of this systematic review and meta-analysis indicates that the probability of post procedural haematoma was 4.76%, haemorrhage 1.43%, perforation 1.11% pseudoaneurysm 1.06%, spasm 0.9%, thrombus 0.55%, neuropathy 0.53%, occlusion 0.51%, ischaemia 0.37% and infection 0.24 %. Non-target vessel puncture, stenosis and stroke had a 0% incidence among the assessed population. This study provides evidence to support clinical decision making when it comes to the utility of pBAA in endovascular diagnosis or therapy. The results demonstrate that pBAA is relatively safe with a low incidence of serious complications and thereby provide the clinician with the option of an alternate access point when planning treatment.

Peripheral venous dilation using flow-mediated dilation response: A randomized crossover study.

Venodilation is crucial in enhancing the success rate of peripheral intravenous cannulation. Flow-mediated dilation (FMD) is a vasodilatory response initiated by temporary ischemia followed by reperfusion. This crossover study aimed to test the hypothesis that FMD induces dilation of the peripheral veins of the forearm. Fifteen healthy volunteers underwent the FMD and control conditions in a randomized order. FMD involved a 5-min occlusion of blood flow in the brachial artery, followed by reperfusion, achieved by inflating and deflating a cuff placed on the upper arm. The control condition involved participants remaining at rest. The primary outcome measure was a change in the cross-sectional area of the cephalic vein post-intervention. The secondary outcomes included changes in venous diameter and perfusion index (PI). FMD significantly increased the cross-sectional area of the cephalic vein compared with the control condition (relative change to baseline: 37.7% (31.4) vs 2.2% (11.7)), with a mean difference of 35.4% (95% confidence interval (CI): 16.4-54.5, p = 0.001). Both longitudinal and transverse diameters were significantly expanded with FMD compared to the control (relative change to baseline: 15.7% (15.4) vs 2.6% (3.6), p = 0.004; 18.9% (15.6) vs -0.0 (10.2), p = 0.003, respectively). Additionally, PI significantly increased with FMD compared with the control (relative change to baseline: 77.8% (56.9) vs 14.6% (36.0)), with a mean difference of 63.2% (95% CI: 31.2-95.2, p = 0.001). FMD application induced dilation of the cephalic vein of the forearm. The findings suggest that FMD is an effective technique for dilating the venous area and potentially improving the success rate of peripheral intravenous cannulation.

Comparison of Adiposomal Lipids between Obese and Non-Obese Individuals.

Our recent findings revealed that human adipose tissues (AT)-derived extracellular vesicles (adiposomes) vary in cargo among obese and lean individuals. The main objective of this study was to investigate the adiposomal lipid profiles and their correlation with cardiometabolic risk factors. AT samples were collected from obese subjects and lean controls and analyzed for their characteristics and lipid content. In addition, we measured the correlation between adiposomal lipid profiles and body composition, glucose and lipid metabolic profiles, brachial artery vasoreactivity, AT arteriolar flow-induced dilation, and circulating markers such as IL-6, C-reactive protein, and nitric oxide (NO). Compared to lean controls, adiposomes isolated from obese subjects were higher in number after normalization to AT volume. The two major lipid classes differentially expressed were lysophosphatidylcholine/phosphatidylcholine (LPC/PC) and ceramides (Cer). All lipids in the LPC/PC class were several-fold lower in adiposomes from obese subjects compared to lean controls, on top of which were PC 18:2, PC 18:1, and PC 36:3. Most ceramides were markedly upregulated in the obese group, especially Cer d37:0, Cer d18:0, and Cer d39:0. Regression analyses revealed associations between adiposomal lipid profiles and several cardiometabolic risk factors such as body mass index (BMI), fat percentage, insulin resistance, arteriolar and brachial artery vasoreactivity, NO bioavailability, and high-density lipoproteins (HDL-C). We conclude that the ability of adiposomes from obese subjects to disrupt cardiometabolic function could be partly attributed to the dysregulated lipid cargo.

Cardiac Biomarkers are Associated with Incident Fracture Risk in Advanced Chronic Kidney Disease

Cardiovascular disease is associated with increased fracture risk in the general population. Few data exist on the association between cardiovascular health and incident fracture risk in patients with advanced CKD, a high-risk population for fractures. We aimed to assess the link between fracture risk and cardiovascular health in a prospective cohort of 210 patients with CKD stage G4–5. Incident fractures were recorded during a prospective follow-up of 5 years. Laboratory parameters, abdominal aortic calcification score, echocardiography, ultrasound assessment of brachial artery flow-mediated dilatation and carotid intima-media thickness, and maximal stress ergometry were obtained at baseline. A total of 51 fractures were observed in 40 (19%) patients during follow-up. In separate multivariable Cox proportional hazards models adjusted for age, gender, and baseline eGFR, TnT (HR 1.007, CI 95% 1.003–1.010, p < 0.001) and ProBNP (HR 1.000, CI 95% 1.000–1.000, p = 0.017) were associated with incident fractures and the association persisted after adjusting for coronary artery disease (CAD). The patients unable to perform the ergometry test had a higher risk of incident fractures compared to others (36.1% vs 15.5%, p = 0.009). A cardiovascular composite risk score summarizing TnT, ProBNP, and ergometry data was independently associated with incident fractures in a multivariable Cox model (HR 1.373, CI 95% 1.180–1.599, p < 0.001). Patients with the lowest score were observed with no fractures, while patients with the highest score were observed with a fracture risk of 40.5% during follow-up. Risk of incident fractures is associated with biomarkers of cardiovascular health and a composite cardiovascular risk score in patients with advanced CKD.

Flow-Mediated Dilatation: Learning Curve Study with a Novice Operator

BackgroundPerforming reproducible flow-mediated dilatation (FMD) measurements can be challenging, especially among inexperienced operators. Our aim was to present the detailed learning curve of a novice operator.MethodsFollowing a one-week basic training period, the operator performed duplicate measurements on 6–8 individuals per week, for six weeks. The operator followed the recommendations of the most recent guideline. Duplex ultrasound was used for the simultaneous and continuous measurement of brachial artery diameter and local blood flow velocity. Following a 1-min recording of baseline diameter (D), FMD was measured after a 5-min period of occlusion of the proximal forearm vessels. Inter-session coefficient of variation (CV) values for D and FMD were calculated for each week.ResultsThe number of volunteers assessed each week were the following: 8, 7, 7, 6, 7, 7 individuals. CV values for both D and FMD exhibited a decreasing trend over the training period, ending at 1.73% for D and 14.24% for FMD at week 6. These CV values are within the range outlined in the most recent FMD guideline for proficiency.ConclusionWithin a reasonable timeframe, and with careful adherence to measurement guidelines, the attainment of sound reproducibility in FMD measurements by a novice operator is feasible.

Assessment of Sonographic Parameters for Predicting Primary Patency Rate in Hemodialysis Patients With Venous Valve-Related Stenosis.

Ultrasonography is more frequently used in patients with arteriovenous fistula (AVF) stenosis. The aim of this study is to use sonographic parameters for predicting primary patency in hemodialysis patients with venous valve-related stenosis (VVRS) who are treated by ultrasound-guided percutaneous transluminal angioplasty (PTA). A total of 229 VVRS patients who underwent PTA between January 2017 and December 2021 were enrolled. Clinical characteristics were retrospectively collected. Sonographic parameters were measured both before and after PTA. Univariate and multivariate Cox analyses were performed to identify independent factors associated with primary patency rate. All measured sonographic parameters improved after PTA compared to before PTA. Before PTA, the diameter of VVRS > 1.0 mm, age ≤ 57 years, and body mass index (BMI) > 21.57 kg/m2 were associated with better outcomes. While the diameter of radial artery, proximal radial artery close to the anastomosis, brachial artery, the flow volume of brachial artery, the length and peak velocity (PV) of the VVRS, and the diameter and PV after the VVRS had no association with the primary patency rate. After PTA, only patients with a diameter of VVRS > 4.0 mm had favorable outcome. In addition, patients with a gain of diameter of VVRS > 2.4 mm after PTA had a trend of better outcomes. The diameter of VVRS before and after PTA could be served as markers to predict primary patency rate and second patency rate in AVF patients with VVRS. The gain of diameter of VVRS could also be a potential marker. Using simple markers of sonographic parameters, we could quickly identify patients with a higher risk of restenosis. These patients should be followed more closely in case of restenosis at early. It is also beneficial to the prevention of thrombosis. These measures help to preserve more valuable vascular for a long-term dialysis. Additionally, the physician should pay more attention on the dialysis-related complications in these risky patients, such as hemodialysis-related hypotension.

The stiffness of the brachial artery varies from that of the aorta concerning cardiovascular risk factors

The stiffness of the brachial artery varies from that of the aorta concerning cardiovascular risk factors