Resistive Index Measurements Research Articles

Functional improvement of non-infarct related coronary artery stenosis by extensive LDL-C reduction with a PCSK9 antibody: the FITTER trial, microvascular function analysis

Abstract Background Atherosclerosis and microvascular dysfunction are closely linked. Moreover, impaired microvascular function is strongly associated with increased risk on major adverse cardiac events. In patients presenting with acute coronary syndrome (ACS), microvascular function is reduced. PCSK9-inhibitors have shown to reduce plaque burden and lipid load in epicardial vessels and might exhibit similar results on microvascular vessels, thereby improving microvascular function. The FITTER trial offers the unique opportunity to test this hypothesis. Methods The FITTER trial is a multi-center, randomized, double blind, placebo controlled clinical trial for patients presenting with ACS and multi-vessel disease (MVD). After treatment of the culprit lesion, fractional flow reserve (FFR) measurement of non-infarct related artery (non-IRA) lesions was performed. Patients with intermediate, non-critical lesions (FFR: 0.67-0.85) were included in this trial. For exploratory purpose, additional physiological assessment of the non-IRA included coronary flow reserve (CFR) and microvascular resistance index (IMR) measurements. Microvascular function was evaluated using a pressure- and temperature-sensitive guidewire and a bolus thermodilution method. Participants were randomized and treated for 12 weeks with either evolocumab or placebo in addition to high-intensity statin therapy. Staged reevaluation was done at 12 weeks. After repeated physiology testing, PCI was performed if deemed necessary. Pre-defined exploratory analysis includes the absolute and relative difference in change between CFR and IMR from baseline to follow up in the non-IRA. PCSK9 inhibition might result in a relatively larger increase of CFR and larger decrease of IMR. Results Between March 2020 and August 2023, a total of 150 patients were included in the trial. In 61 patients (88.5% male, age 65.3 ± 9.1 years, 23.0% STEMI, 70.5% non-STEMI, 6.6% UAP) successful baseline and follow-up measurements of microvascular function were performed. Complete results will be available at the beginning of March 2024. The primary- and secondary endpoints will be submitted for late-breaking clinical trials selection. The results of this abstract will include a per vessel analysis of coronary artery microvascular function. Conclusion The FITTER trial will provide new insights on the potential of extensive LDL-C reduction with a PCSK9 antibody on microvascular coronary artery function in patients presenting with ACS and MVD.

Blood Flow of the Infraspinatus Muscle in Individuals With and Without Shoulder Pain and Myofascial Trigger Points: A Color Doppler Ultrasound and Reliability Study.

Myofascial trigger points (MTrPs) are potential contributors to shoulder pain and can lead to local ischemia and hypoxia, thus causing pain. Color Doppler ultrasound (US) has been used to examine the vascular environment around MTrPs, but has not been used to examine blood flow impairments in patients with shoulder pain and MTrPs. The reliability of color Doppler US for measuring infraspinatus muscle blood flow also has not been established. This study aimed to investigate differences in blood flow between individuals with and without shoulder pain and the reliability of Doppler US for measuring infraspinatus muscle blood flow. Forty participants were enrolled, 20 with shoulder pain and MTrPs and 20 without. Color Doppler US examination was performed twice on each participant to measure peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI), and pulsatile index (PI) of the infraspinatus muscle. The symptomatic participants had significantly higher PSV (ie, impaired blood flow) than the asymptomatic participants. There were no significant between-group differences in EDV, RI, and PI. The results also demonstrated good-to-excellent intra-rater reliability for color Doppler US measurements of PSV, EDV, RI, and PI for both groups. This study demonstrated differences in blood flow near MTrPs in the infraspinatus muscle between individuals with and without shoulder pain. It also established good-to-excellent reliability of color Doppler US in measuring infraspinatus muscle blood flow. These findings suggest color Doppler US is a useful tool to identify vascular impairments for shoulder pain associated with MTrPs.

Using Doppler duplex ultrasound to determine hemodynamic alterations in renal vasculature: Crucial pathophysiological event preceding renal dysfunction in decompensated cirrhosis

BackgroundRenal dysfunction is a watershed event in cirrhosis, often preceded by renal vasoconstriction. However, our reliability on elevated serum creatinine often delays interventions. Measurement of Renal Resistive Index (RI) and Renal Venous Stasis Index (RVSI) by Doppler ultrasound offers insight into renal vasoconstriction. MethodsFifty participants with decompensated cirrhosis with ascites and normal serum creatinine underwent renal Doppler ultrasound for the measurement of RI and RVSI. All patients were compliant with a salt-restricted diet. Individuals aged <18 years, hepatocellular carcinoma, non-cirrhosis-related ascites, pre-existing renal disease, obstructive uropathy, or history of nephrotoxic medication use were excluded. Statistical analyses, including Pearson correlation, regression analysis, and Chi-square/Fisher’s exact tests, were performed to assess the statistical significance between RI, RVSI, and renal parameters. Additionally, the association of RI with the model for end-stage liver disease sodium (MELD-Na) and Child-Turcotte-Pugh (CTP) scores was also assessed. ResultsMajority were males (88%), average CTP score was 11.7, mean MELD-Na score was 20.92, and mean serum creatinine was 1.05 mg/dL. Renal parameters had varying RI values among renal arteries, with the main right and left arteries at 0.615 [standard deviation (SD): 0.089] and 0.638 (SD: 0.083), respectively. RI and RVSI are significantly correlated with serum creatinine. Further, significant correlation between, RI, RVSI values noted with MELD-Na score even when serum creatinine values are normal. ConclusionStrong correlations between serum creatinine, RI, and MELD-Na scores hints at predictive clinical potential. Future research with larger cohorts and extended follow-up is required to gauge clinical utility and its impact on outcomes.

Role of endogenous GLP-1 on arterial stiffness and renal haemodynamics following bariatric surgery.

Cardiovascular trials have revealed the positive impact of GLP-1 receptor agonists (GLP-1 RAs) on cardiovascular outcomes in type 2 diabetes (T2D). However, the specific effects of endogenous GLP-1 on arterial stiffness and renal function remain understudied. This study aimed to explore the influence of endogenous GLP-1 response post-bariatric surgery on arterial stiffness and renal haemodynamic. Thirty individuals with morbid obesity and without T2D, scheduled for Roux-en-Y Gastric Bypass (RYGB), were included. Clinical parameters, 3-hour oral glucose tolerance test (OGTT) with serial sampling for glycaemia, GLP-1 and insulin, carotid-femoral pulse wave velocity (cf-PWV), carotid distensibility coefficient (carotid-DC) and renal resistive index (RRI) measurements were conducted pre-surgery and 1-year post-surgery. Participants were categorized into high-response and low-response groups based on their post-surgery increase in GLP-1 (median increase of 104% and 1%, respectively, pre- vs. post-surgery). Post-surgery, high-response group demonstrated a greater reduction in cf-PWV (p = .033) and a greater increase (p = .043) in carotid DC compared to low-response group. These enhancements were observed independently of weight loss or blood pressure changes. High-response group exhibited a reduction in RRI (p = .034), although this association was influenced by improvement in pulse pressure. Finally, a multivariate stepwise regression analysis indicated that the percentage increase of GLP1, Δ-GLP1(AUC)%, was the best predictor of percentage decrease in cf-PWV (p = .014). Elevated endogenous GLP-1 response following RYGB was associated with improved arterial stiffness and renal resistances, suggesting potential cardio-renal benefits. The findings underscore the potential role of endogenous GLP-1 in influencing vascular and renal haemodynamics independent of traditional weight loss.

Effect of different shock conditions on mesenteric hemodynamics

Background: Reduced effective circulating blood volume and impaired peripheral tissue perfusion play an important role in the pathophysiology of shock. However, there have been no studies examining the relationship between Doppler ultrasound of the superior mesenteric artery (SMA) under different shock conditions.Methods: We evaluated a total of 85 patients, including 63 patients with different types of shock and 22 in the control group. we included patients who were diagnosed with shock upon admission or developed shock during their hospital stay. At the same time, patients with stable hemodynamics, no use of vasoactive drugs and normal lactate levels were used as a control group. We collected SMA Doppler ultrasound parameters, including Peak Systolic Velocity (PSV), End Diastolic Velocity (EDV), Resistance Index (RI), pulsatility index (PI), Time-Averaged Mean Velocity (TAMV), and Blood Flow (BF).Results: In the cardiac shock group, SMA PSV, TAMV, and BF were lower compared to the other groups. There was no significant difference in SMA RI and PI between the different types of shock groups, but both were significantly lower than the control group. Cardiac index (CI) is correlated with SMA PSV (r = 0.487, P = 0.000) and TAMV (r = 0.538, P = 0.000), whereas SVRI is not correlated with SMA RI and PI. Lactate levels was correlation with SMA RI (r = -0.307, P = 0.000) and PI (r = -0.287, P = 0.000). The area under the ROC curve of SMA RI and PI to predict hyperlactatemia was 0.85[0.78-0.91] and 0.83[0.76–0.90].Conclusions: The velocity parameters of SMA Doppler ultrasound such as TAMV and PSV can reflect cardiac function. The measurements of SMA RI and PI are correlated with lactate levels, having a positive predictive value for hyperlactatemia and provide guidance for fluid resuscitation in patients with shock in the future.

Renal resistive index measurements by ultrasound in patients with liver cirrhosis: Magnitude and associations with renal dysfunction

BACKGROUND The hemodynamic alterations seen in liver cirrhosis lead to renal vasoconstriction, ultimately causing acute kidney injury (AKI). The renal resistive index (RRI) is the most common Doppler ultrasound variable for measuring intrarenal vascular resistance. AIM To evaluate the association of the RRI with AKI in patients with liver cirrhosis and to identify risk factors for high RRI. METHODS This was a prospective observational study, where RRI was measured using Doppler ultrasound in 200 consecutive hospitalized patients with cirrhosis. The association of RRI with AKI was studied. The receiver operating characteristic (ROC) curve analysis was utilized to determine discriminatory cut-offs of RRI for various AKI phenotypes. Multivariate analysis was conducted to determine the predictors of high RRI. RESULTS The mean patient age was 49.08 ± 11.68 years, with the majority (79.5%) being male; the predominant etiology of cirrhosis was alcohol (39%). The mean RRI for the study cohort was 0.68 ± 0.09, showing a progressive increase with higher Child-Pugh class of cirrhosis. Overall, AKI was present in 129 (64.5%) patients. The mean RRI was significantly higher in patients with AKI compared to those without it (0.72 ± 0.06 vs 0.60 ± 0.08; P &lt; 0.001). A total of 82 patients (41%) had hepatorenal syndrome (HRS)-AKI, 29 (22.4%) had prerenal AKI (PRA), and 18 (13.9%) had acute tubular necrosis (ATN)-AKI. The mean RRI was significantly higher in the ATN-AKI (0.80 ± 0.02) and HRS-AKI (0.73 ± 0.03) groups than in the PRA (0.63 ± 0.07) and non-AKI (0.60 ± 0.07) groups. RRI demonstrated excellent discriminatory ability in distinguishing ATN-AKI from non-ATN-AKI (area under ROC curve: 93.9%). AKI emerged as an independent predictor of high RRI (adjusted odds ratio [OR]: 11.52), and high RRI independently predicted mortality among AKI patients (adjusted OR: 3.18). CONCLUSION In cirrhosis patients, RRI exhibited a significant association with AKI, effectively differentiated between AKI phenotypes, and predicted AKI mortality.

Relation between interleukin-13 and annexin-V levels and carotid intima-media thickness in nephrotic syndrome.

The aim of the current study is to assess the relation between carotid intima-media thickness (CIMT) measurements, renal Doppler resistive index (RI) and serum levels of interleukin-13 (IL-13) and annexin-V (An-V) in children with idiopathic nephrotic syndrome (INS). The present case-control study was conducted on 60 children with INS and 60 age- and sex-matched healthy children. All participants were subjected to evaluation of serum levels of IL-13 and An-V and ultrasound Doppler measurement of CIMT and renal RI. Patients expressed significantly higher An-V (5.9 ± 2.6 vs. 2.1 ± 0.8 ng/mL, p<0.001) and IL-13 (19.2 ± 7.6 vs. 3.4 ± 1.4 ng/L) levels when compared with healthy counterparts. Moreover, it was shown that patients had significantly higher CIMT (0.49 ± 0.06 vs. 0.35 ± 0.03, p<0.001) as compared to controls. No significant differences were noted between the studied groups regarding right or left RIs. Correlation analysis identified significant direct correlation between serum An-V levels and albumin/creatinine ratio (ACR) (r = 0.55), cholesterol (r = 0.48), triglycerides (r = 0.36), IL-13 (r = 0.92) and CIMT (r = 0.53). Similar correlations could be found between serum IL-13 levels and CIMT measurements and the corresponding parameters. The present study suggests an association between higher early atherosclerosis expressed as elevated CIMT measurements in children with INS and elevated serum levels of An-V and IL-13.

Correlation between the radial artery resistance index and the systemic vascular resistance index: a cross-sectional study.

Ultrasound measurement of the radial resistance index (RRI) in the anatomical snuffbox has been proposed as a useful method for assessing the systemic vascular resistance index (SVRI). This study aims to establish the correlation between SVRI measured by pulmonary artery catheter (PAC) and RRI. A cross-sectional study included all consecutive patients undergoing postoperative (POP) cardiac surgery with hemodynamic monitoring using PAC. Hemodynamic assessment was performed using PAC, and RRI was measured with ultrasound in the anatomical snuffbox. The Pearson correlation test was used to establish the correlation between RRI and SVRI measured using PAC. Hemodynamic behavior concerning RRI with a cutoff point of 1.1 (described to estimate under SVRI) was examined. Additionally, consistency between two evaluators was assessed for RRI using the intraclass correlation coefficient and Bland-Altman analysis. A total of 35 measurements were obtained. The average cardiac index (CI) was 2.73 ± 0.64L/min/m², and the average SVRI was 1967.47 ± 478.33 dyn·s·m²/cm5. The correlation between RRI and SVRI measured using PAC was 0.37 [95% CI 0.045-0.62]. The average RRI was 0.94 ± 0.11. RRI measurements > 1.1 had a mean SVRI of 2120.79 ± 673.48 dyn·s·m²/cm5, while RRI measurements ≤ 1.1 had a mean SVRI of 1953.1 ± 468.17 dyn·s·m²/cm5 (p = 0.62). The consistency between evaluators showed an intraclass correlation coefficient of 0.88 [95% CI 0.78-0.93], and Bland-Altman analysis illustrated adequate agreement of RRI evaluators. For patients in cardiac surgery POP, the correlation between the SVRI measured using PAC and the RRI measured in the anatomical snuffbox is low. Using the RRI as a SVRI estimator for patients is not recommended in this clinical scenario.

Non-mass-type ductal carcinoma in situ of the breast on ultrasound: Features and pathological analysis.

The aims of this study were to investigate the ultrasound features of non-mass-type ductal carcinoma in situ (DCIS) of the breast and conduct a pathological analysis. Ultrasound images of 32 cases of non-mass-type DCIS of the breast, collected between September 2014 and June 2016, were analyzed. The characteristics of the lesions, including border, internal echogenicity, local glandular hyperplasia, micro-calcification, and intra-tumoral blood flow resistance index (RI), were analyzed, and a concurrent pathological analysis was conducted. Obvious local glandular hyperplasia was commonly observed in the 32 cases of non-mass-type DCIS of the breast. The internal echogenicity varied in intensity, exhibiting a "leopard pattern" or "zebra pattern." Color Doppler imaging revealed abundant blood flow signals within the lesion with an RI of >0.7. Isolated duct dilatation and micro-calcifications were occasionally observed within the lesions. High-grade DCIS was the predominant pathological type of non-mass-type DCIS. Non-mass-type DCIS of the breast often presents with obvious local glandular hyperplasia and varying internal echogenicity. High-grade DCIS is the frequent pathological type. Color Doppler imaging and RI measurement can assist in diagnosing non-mass-type DCIS of the breast.

Does central venous stenosis affects the brachial artery flow volume and peripheral vascular resistive index in patients on maintenance hemodialysis? A retrospective study.

A well-functioning vascular access (VA) is crucial for the patients on maintenance hemodialysis (HD). Central venous stenosis (CVS) is a common, yet, overlooked complication of VA as its diagnosis is challenging. Moreover, its effect on the flow volume (FV) and the peripheral resistive index (RI) was not well discussed before. Despite the availability of doppler ultrasound (DUS) in most centers, direct visualization of central veins using DUS is quite difficult. This is a retrospective single-center self-controlled cohort study that was conducted in a specialized vascular access management tertiary center in Japan and included all patients with CVS who underwent percutaneous transluminal angiography (PTA) with or without vascular stenting in the period from January 2014 to September 2022. The patients were divided according to their VA type into arteriovenous fistula (AVF), and arteriovenous graft (AVG) groups, then subdivided, according to the type of stenosis, into two subgroups: CVS, and mixed central and peripheral venous stenosis (MVS) groups. The FV and RI of the feeding artery were compared in the same procedure before and after PTA to assess the impact of the procedure itself. Data of 485 percutaneous transluminal angiography procedures (PTA), performed in 95 patients during the period from January 2014 to September 2022, were collected. FV and RI were significantly affected in the patients with MVS than patients with CVS. After PTA, both FV and RI were significantly improved. The improvement rate of FV and RI after PTA were significantly higher in patients with MVS than patients with CVS. However, it was difficult to determine the cut-off value to diagnose or to assess the improvement of CVS. Our findings suggest that FV and RI measurement by DUS are good tools, along with the clinical findings for assessment of CVS in certain situations.

Quantification of brain-wide vascular resistivity via ultrafast Doppler in human neonates helps early detection of white matter injury

Preterm birth is associated with cerebrovascular development disruption and can induce white matter injuries (WMI). Transfontanellar ultrasound Doppler is the most widely used clinical imaging technique to monitor neonatal cerebral vascularisation and haemodynamics based on vascular indexes such as the resistivity index (RI); however, it has poor predictive value for brain damage. Indeed, these RI measurements are currently limited to large vessels, leading to a very limited probing of the brain’s vascularisation, which may hinder prognosis. Here we show that ultrafast Doppler imaging (UfD) enables simultaneous quantification, in the whole field of view, of the local RI and vessel diameter, even in small vessels. Combining both pieces of information, we defined two new comprehensive resistivity parameters of the vascular trees. First, we showed that our technique is more sensitive in the early characterisation of the RI modifications between term and preterm neonates and for the first time we could show that the RI depends both on the vessel diameter and vascular territory. We then showed that our parameters can be used for early prediction of WMI. Our results demonstrate the potential of UfD to provide new biomarkers and pave the way for continuous monitoring of neonatal brain resistivity.

First Real-Life Data on the Diving Response in Healthy Children.

Swimming and diving are popular recreational activities, representing an effective option in maintaining and improving cardiovascular fitness in healthy people. To date, only little is known about the cardiovascular adaption to submersion in children. This study was conducted to improve an understanding thereof. We used a stepwise apnea protocol with apnea at rest, apnea with facial immersion, and at last apnea during whole body submersion. Continuous measurement of heart rate, oxygen saturation, and peripheral resistance index was done. Physiologic data and analysis of influencing factors on heart rate, oxygen saturation, and peripheral vascular tone response are reported. The current study presents the first data of physiologic diving response in children. Data showed that facial or whole body submersion leads to a major drop in heart rate, and increase of peripheral resistance, while the oxygen saturation seems to be unaffected by static apnea in most children, with apnea times of up to 75s without change in oxygen saturation.

Orbital Doppler ultrasonography evaluation in patients with ankylosing spondylitis: A prospective study.

Our aim in this study is to compare patients with ankylosing spondylitis (AS), a rheumatologic disease that can cause eye involvement and the normal population in terms of orbital Doppler findings, which is an inexpensive and easily applicable method that can be used in early diagnosis and follow-up. The study was planned prospectively. The data of patients with AS were compared to those of age- and gender-matched healthy volunteers. A total of 42 participants, 23 (54.8%) males and 19 (45.2%) females, with a mean age of 42.4±12.6 years were included in the study. In addition to demographic information, such as age and gender, the diameter, peak systolic velocity, end-diastolic velocity, mean velocity, resistive index, pulsatility index, and blood flow volumes of the central retinal artery of the left eye were measured using spectral Doppler ultrasonography. According to the comparison of the patients with and without AS according to orbital Doppler ultrasonography findings, the mean velocity, resistive index, and volume measurements of the patients with AS were significantly higher than those without AS (p=0.028, p=0.039, and p=0.038, respectively). However, in the subgroup analysis of the AS group, the Doppler findings did not significantly differ between the patients with and without anterior uveitis. In the patient group with AS, independent of anterior uveitis (AU), there was a difference in Doppler parameters and therefore in ophthalmic vasculature. In patients with AS, orbital vascularity changes can be detected with orbital Doppler US before clinical signs appear.

Argipressin-norepinephrine association in the treatment of septic shock: the use of the polydistrectual resistance index as an assessment of vascular compliance

IntroductionThe hemodynamic management of septic patients involves initial fluid therapy, followed by the use of vasoconstrictors in case of treatment failure. The latest Surviving Sepsis Campaign guidelines suggest the synergistic use of argipressin in addition to norepinephrine when hemodynamic optimization is not achieved with norepinephrine alone.MethodsIn our single-center retrospective observational study, the primary endpoint is the safety of initial norepinephrine-argipressin association treatment, assessed through a reduction in Resistance Index. Our secondary endpoint includes the efficacy of this combination, measured by an increase in Mean Arterial Pressure and a reduction in Resistance Index as an indicator of organ perfusion. The Resistance Index (RI) is evaluated through Power Doppler ultrasound. RI is crucial for assessing multi-district vascular tone and multiorgan perfusion. Patients were categorized into three groups based on their treatment. In Group 1, we analyzed patients treated with norepinephrine alone in incremental doses; in Group 2, we analyzed patients receiving the initial norepinephrine-argipressin association treatment (norepinephrine 0.05 mcg/kg/min-argipressin 0.03 IU/min); in the third group (Group 3), we analyzed patients given argipressin (0.03 IU/min) after norepinephrine (&amp;lt;0.10–0.25≥ mcg/kg/min) to stabilize their hemodynamics (MAP &amp;gt; 65 mmHg). RI measurements were taken in the Renal Artery (ARE), Radial Artery (AR), Central Retinal Artery (CRA), and Superior Mesenteric Artery (AMS) at four different time points: T0 before vasopressor therapy, T1 at 1 h, T2 at 24 h, and T3 at 48 h after vasopressor infusion.ResultsA total of 48 patients were divided into three groups: 17 patients in Group 1, 16 in Group 2, and 15 in Group 3. In Group 1, an increase in Mean Arterial Pressure (MAP) was observed, but there was an increase in RIs in the right CRI and left ARE. In Group 2, there was an improvement in MAP and a reduction in RIs in the right/left CRI, left ARE, AMS, and right AR. In Group 3, there was an increase in MAP and a reduction in RIs in the right/left CRI, left ARE, AMS, and right AR.ConclusionEarly norepinephrine-argipressin association treatment appears to be a valid strategy for hemodynamic optimization in this patient population.

Non-albumin proteinuria marks tubular involvement and is associated with arterial stiffness in subjects affected by severe obesity

IntroductionObesity is a well-established risk factor for kidney disease, and tubular damage can play a pivotal role in the development of obesity-related kidney damage. This study aimed to investigate the pathophysiological pathways involved in the development of non-albumin proteinuria (NAP), a marker of tubular involvement, in a cohort of subjects with severe obesity and preserved kidney function. MethodsA total of 106 subjects with BMI ≥ 35 kg/m2 in waiting list for bariatric surgery underwent blood chemistry analysis including metabolic and lipid profile, vascular tests for cardiovascular risk stratification and a comprehensive assessment of kidney function, including renal resistive index (RRI) and NAP measurement. ResultsNineteen patients with ACR ≥ 30 mg/g regardless of NAP values (ALB+), nineteen with NAP≥ 150 mg/g and albuminuria < 30 mg/g (iNAP) and sixty-eight without proteinuria (No-P) were found. Both ALB+ and iNAP groups exhibited a higher prevalence of hypertension and anti-hypertensive treatment compared to No-P, while the prevalence of diabetes was similar between groups. Concerning lipid profile, no differences in total, HDL and LDL cholesterol were found, while ALB+ patients had higher serum triglyceride levels than the other two groups. RRI and carotid-femoral pulse wave velocity (cf-PWV) was significantly higher in ALB+ and iNAP groups compared to No-P. Remarkably, cf-PWV remained still significant after adjustment for age, sex and MBP (p = 0.0004). In overall population, a multiple regression analysis showed that cf-PWV was an independent determinant of NAP in a model including age, sex, glycated hemoglobin, systolic and mean blood pressure (R2 =0.17, p = 0.031). ConclusioniNAP subjects showed increased arterial stiffness comparable to that observed in ALB+ group, suggesting that they may represent a subgroup at higher cardiovascular risk, often unrecognized in clinical practice.

THU417 Associations Between Glucose Metabolism And Trabecular Bone Score In Subjects With Acromegaly

Abstract Disclosure: M. Kuzma: None. J. Payer: None. P. Vanuga: None. I. Sagova: None. D. Pavai: None. P. Jackuliak: None. Z. Killinger: None. Introduction: Previously, it was thought that increased risk of vertebral fractures (VF) in acromegaly is associated with impaired trabecular bone. More recently, cortical bone was proposed as one of the fracture risk determinant. However, trabecular compartment is still decreased. Glucose intolerance is a frequent complication of acromegaly and is directly attributable to the excess circulating growth hormone and IGF-1 concentrations and thus possibly lead to trabecular bone detoriation.Objectives: To assess effect of glucose metabolism on DXA-derived bone parameters, such as bone mineral density (BMD), trabecular bone score (TBS), cortical and trabecular vBMD, surface BMD and cortical thickness of proximal femur among patients with acromegaly. Patients and methods: In total, 70 consecutive patients (24 males/56 female, mean age = 55.6 years) with acromegaly based on current ADA guidelines were divided in two subgroups according to glucose metabolism(GM): abnormal GM (n=35; 14 males/21 females; 15 with active disease) and normal GM (n=35;10 Males /25 Females; 11 with active disease). Subjects were prospectively followed up for two years. At baseline and year 2; all subjects had pituitary hormonal measures, fasting plasma glucose (FPG), HBA1c, C-peptide, insulin resistance index (IRI) and DXA measurement performed. From DXA, BMD, TBS and 3D-Shaper parameters were derived. Results: At baseline; subjects with abnormal GM had lower TBS (1.166±0.15) in comparison to normal GM subjects (1.232±0.12; p&amp;lt;0.05). Insulin like growth factor 1 (IGF-1), FPG, HBA1c, C-peptide, IRI and bone parameters was correlated in simple regression model. FPG, HBA1c, C-peptide and IRI was negatively associated with TBS. No correlation between GM parameters and other bone measures was observed. Multiple regression model of all GM parameters weighted by IGF-1 revealed HBA1c as a significant predictor of TBS value (Estimate =-0,054; p=0.04). At year 2; FPG and HBA1c was negatively associated with TBS. In multiple regression IGF-1-weighted model, no significant predictor of TBS was observed. Conclusion: Acromegaly subjects with abnormal GM have lower TBS in comparison to those with normal GM. The best GM parameter to predict TBS in acromegaly was HBA1c. This study showed that trabecular bone microstructure, as indirectly assessed by TBS, is likely resulting of impaired glucose metabolism. Presentation: Thursday, June 15, 2023

Water immersion ultrasound can improve the repeatability of ultrasonic measurement of dorsalis pedis artery diameter and hemodynamic parameters.

In comparing the repeatability of the internal diameter and hemodynamic parameters of the dorsalis pedis artery measured by immersion ultrasound and contact ultrasound, the factors affecting the accuracy and repeatability of measurement were analyzed. This study aimed to provide a better method for ultrasound evaluation of the dorsalis pedis artery before flap transplantation. Two senior sonographers measured the diameter of the dorsalis pedis artery (D) of 56 healthy volunteers, measuring at the same location and at different time points using water immersion and contact ultrasound. Color Doppler ultrasound was used to measure the hemodynamics of the dorsalis pedis artery, including peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI). The interclass correlation coefficient (ICC) was used to evaluate the intraobserver and interobserver repeatability for each group's measurements. The intraobserver and interobserver reproducibility of D, PSV, EDV, and RI measurements by water immersion ultrasound was very good. The intraobserver and interobserver reproducibility of the contact ultrasound measurements of D, PSV, EDV, and RI was good. The repeatability of water immersion ultrasound is better than that of contact ultrasound in the measurement of the dorsalis pedis artery. Water immersion ultrasound can improve the near-field resolution of superficial tissues and increase the display of the lengths of blood vessels in images, thereby suggesting its superiority in ultrasound examination of dorsalis pedis arteries.

Utility of renal resistive index measurement in juvenile systemic lupus erythematosus: a cross-sectional single-center study.

Systemic lupus erythematosus (SLE) is a multisystemic autoimmune disease with a complex etiopathogenesis. Renal involvement is the most common and devastating complication of the disease. Renal resistive index (RRI) was suggested as a noninvasive biomarker for lupus nephritis in previous studies. This is the first study to investigate the role of RRI measurement in juvenile SLE patients. This cross-sectional study included 25 juvenile SLE patients and 25 healthy controls. Demographic and clinical features were recruited from the medical files of the patients. RRI measurements were performed with color Doppler ultrasonography from intrarenal arteries when Doppler angles were 30-60 in right and left kidneys. Of 25 (19 female, 6 male) SLE patients, nineteen (76%) patients had urinary abnormalities during follow-up, and renal biopsy was performed in 14 patients, of which 9 (64.3%) had class 2 and 5 (35.7%) had class 4 lupus nephritis. RRI was found significantly higher in SLE group than healthy controls. RRI did not differ between SLE patients, grouped according to the presence of renal involvement and class IV lupus nephritis. RRI did not correlate with serum creatinine, GFR, spot urine protein/creatinine, and albumin/creatinine ratio. Although RRI was found significantly higher in juvenile SLE, it is not affected by GFR, proteinuria level, or the renal biopsy results, even the presence of proliferative nephritis. The underlying pathogenetic mechanisms of increased RRI in SLE should be clarified in further studies. Key Points • Renal resistive index (RRI) is a parameter derived from renal Doppler ultrasound imaging and shows the intrarenal arterial resistance. • This study reveals that RRI is increased in juvenile systemic lupus erythematosus. • RRI was previously related with renal involvement, particularly class 4 lupus nephritis in adults. However, RRI was not affected by the presence or degree of renal involvement in juvenile SLE patients in our study.

Normal umbilical artery doppler values in 18–22 week old fetuses with single umbilical artery

Umbilical cord with a single umbilical artery (SUA) can carry twice the blood volume of a three-vessel cord (TVC). So, the normal hemodynamics of the fetuses with SUA was different from those with TVC. Furthermore, structural abnormalities, fetal aneuploidy, and intrinsic growth retardation may be associated with the presence of a SUA. In order to evaluate these patients, intermittent doppler measurements have been suggested. From this point, we aimed to determine the CDUS flow parameters in SUA cases and to demonstrate that these flow parameters are different from the TVC parameters. Ultrasound (US) examinations were performed in the 18–22 weeks of gestation during routine fetal anatomy screening. Resistance index (RI), Pulsatility index (PI), and S/D: systole to diastole ratio values were measured. The samples were taken from the proximal, mid-portion, and distal of the umbilical cord. In addition to Doppler Ultrasound values, AC and estimated fetal weight (EFW) values were also recorded. The study included 167 pregnant women, 86 of whom were study group with SUA and 81 were control group with TVC. The measurements of RI, PI, and S/D at all three levels were significantly lower in the SUA group compared to the TVC group. The resistance in the UA of fetuses with SUA is lower than in fetuses with TVC. The resistance in the UA of fetuses with SUA decreases from the fetal end to the placental end. Knowing the normal values for fetuses with SUA might provide a better and more reliable Doppler Ultrasoundassessment.

Microcirculatory Disease in Patients after Heart Transplantation.

Although the treatment and prognosis of patients after heart transplantation have significantly improved, late graft dysfunction remains a critical problem. Two main subtypes of late graft dysfunction are currently described: acute allograft rejection and cardiac allograft vasculopathy, and microvascular dysfunction appears to be the first stage of both. Studies revealed that coronary microcirculation dysfunction, assessed by invasive methods in the early post-transplant period, correlates with a higher risk of late graft dysfunction and death during long-term follow-up. The index of microcirculatory resistance, measured early after heart transplantation, might identify the patients at higher risk of acute cellular rejection and major adverse cardiovascular events. It may also allow optimization and enhancement of post-transplantation management. Moreover, cardiac allograft vasculopathy is an independent prognostic factor for transplant rejection and survival rate. The studies showed that the index of microcirculatory resistance correlates with anatomic changes and reflects the deteriorating physiology of the epicardial arteries. In conclusion, invasive assessment of the coronary microcirculation, including the measurement of the microcirculatory resistance index, is a promising approach to predict graft dysfunction, especially the acute allograft rejection subtype, during the first year after heart transplantation. However, further advanced studies are needed to fully grasp the importance of microcirculatory dysfunction in patients after heart transplantation.