Peak Systolic Velocity Research Articles

A proof-of-concept study of ultrasound-guided continuous parasacral ischial plane block for postoperative pain control in patients undergoing total knee arthroplasty

BackgroundContinuous peripheral nerve blocks are widely used for anesthesia and postoperative analgesia in lower limb surgeries. The authors aimed to develop a novel continuous sacral plexus block procedure for analgesia during total knee arthroplasty.MethodsThe study comprised two stages. In Stage I, the authors built upon previous theories and technological innovations to develop a novel continuous sacral plexus block method, ultrasound-guided continuous parasacral ischial plane block (UGCPIPB) and subsequently conducted a proof-of-concept study to assess its effectiveness and feasibility. Stage II involved a historical control study to compare clinical outcomes between patients undergoing this new procedure and those receiving the conventional procedure.ResultsThe study observed a 90% success rate in catheter placement. On postoperative day (POD) 1, POD2, and POD3, the median visual analog scale (VAS) scores were 3 (range, 1.5–3.5), 2.5 (1.6–3.2), and 2.7 (1.3–3.4), respectively. Furthermore, 96.3% of the catheters remained in place until POD3, as confirmed by ultrasound. The study revealed a significant increase in skin temperature and peak systolic velocity of the anterior tibial artery on the blocked side compared with those on the non-blocked side. Complications included catheter clogging in one patient and leakage at the insertion site in two patients. In Stage II, the novel technique was found to be more successful than conventional techniques, with a lower catheter displacement rate than the conventional procedure for continuous sciatic nerve block.ConclusionUGCPIPB proved to be an effective procedure and safe for analgesia in total knee arthroplasty.Chinese Clinical Trial Registry NumberChiCTR2300068902.

A meta-analysis: elucidating diagnostic thresholds of peak systolic flow velocities in thyroid arteries for the discrimination of Graves' disease and destructive thyrotoxicosis.

This meta-analysis examines peak systolic velocities (PSVs) in thyroid arteries as potential biomarkers for thyroid disorders, which includes treated and untreated Graves' disease(GD) and destructive thyrotoxicosis(DT). A search across databases including PubMed, Google Scholar, Embase, and Web of Science identified studies assessing peak systolic flow velocity in the inferior thyroid artery (ITA-PSV) and superior thyroid artery (STA-PSV) diagnostic efficacy in GD and DT.And the search was restricted to publications in the English language.The analysis compared STA-PSV and ITA-PSV across patient groups, evaluating intra-group variances and synthesizing sensitivity and specificity data. The analysis covered 18 studies with 1276 GD, 564 DT patients, and 544 controls. The difference of STA-PSV between GD group, DT group and normal group and the difference of ITA-PSV were analyzed in subgroups, and there was no statistical significance between subgroups when comparing any two groups. Normal subjects displayed intra-group ITA-PSV and STA-PSV differences with established cut-off values of 20.33 cm/s (95% CI, 17.48-23.18) for ITA-PSV and 25.61 cm/s (95% CI, 20.37-30.85) for STA-PSV. However, no significant intra-group differences were observed in the STA-PSV and ITA-PSV cut-off values among groups with GD or DT. The combined cut-off values for these patient groups and normal subjects were 68.63 cm/s (95% CI, 59.12-78.13), 32.08 cm/s (95% CI, 25.90-38.27), and 23.18 cm/s (95% CI, 20.09-26.28), respectively. The diagnostic odds ratio(DOR) for these values was 35.86 (95% CI, 18.21-70.60), and the area under the summary receiver operating characteristic (SROC) curve was 0.91, with a sensitivity estimate of 0.842 (95% CI, 0.772-0.866). PSVs in thyroid arteries are useful diagnostic tools in distinguishing DT from GD. A PSV above 68.63 cm/s significantly improves GD diagnosis with up to 91% efficacy. No notable differences were found between superior and inferior thyroid arteries in these conditions.

The effect of endoscopic renal and ureteral stone surgeries on renal blood flow in children: a prospective trial

Aim: To assess the impact of endoscopic stone surgeries on renal perfusion and blood flow in children. Materials and methods: Children who underwent percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), ureterorenoscopy (URS), endoscopic combined intrarenal surgery (ECIRS) were included to the study. Renal Doppler ultrasonography (RDUS) was performed one day before the operation, and on the postoperative 1st day and 1st month. Peak systolic velocity (PSV) and end-diastolic velocity (EDV) were measured, and resistive index (RI) was calculated with the (PSV-EDV)/PSV formula. RDUS parameters were compared before and after surgery and between ipsilateral and contralateral kidneys. Results: A total of 45 children with a median age was 8 (2–17) years were included (15 (33.3%) girls, 30 (66.7%) boys). PCNL was performed in 13 children (28.9%), RIRS 11 (24.4%), URS 12 (26.7%), and ECIRS 9 (20%). There was no significant difference in renal and segmental PSV, EDV and RI values of operated kidney in the preoperative, postoperative periods. There was no significant difference between RDUS parameters of the ipsilateral and contralateral kidneys in preoperative or postoperative periods. PSV and EDV values were significantly higher in the 1st postoperative month in the group without preoperative DJ stent than in the group with DJ stent (p = 0,031, p = 0,041, respectively). However, RI values were similar. The mean RI were below the threshold value of 0.7 in each period. Conclusion: RDUS parameters didn’t show a significant difference in children. Endoscopic surgeries can be safely performed in pediatric stone disease.

Color Duplex Ultrasonography for the Evaluation of Innominate, Subclavian, and Common Carotid Artery Stenosis.

This study aimed to validate the efficiency of Doppler ultrasonography for predicting the innominate, subclavian, and common carotid artery stenosis. This retrospective multicenter study between 2013 and 2022 enrolled 636 patients who underwent carotid Doppler ultrasonography and subsequent digital subtraction angiography. And 58 innominate artery stenosis, 147 common carotid artery stenosis, and 154 subclavian artery stenosis were included. The peak systolic velocity at innominate, subclavian, and common carotid artery, and velocity ratios of innominate artery to common carotid artery, innominate artery to subclavian artery, and common carotid artery to internal carotid artery were measured or calculated. The threshold values were determined using receiver operating characteristic analysis. The threshold values of innominate artery stenosis were peak systolic velocity >206 cm/s (sensitivity: 82.8%; specificity: 91.4%) to predict ≥50% stenosis and >285 cm/s (sensitivity: 89.2%; specificity: 94.9%) to predict ≥70% stenosis. The threshold values of common carotid artery stenosis were peak systolic velocity >175 cm/s (sensitivity: 78.2%; specificity: 91.9%) to predict ≥50% stenosis and >255 cm/s (sensitivity: 87.1%; specificity: 87.2%) to predict ≥70% stenosis. The threshold values of subclavian artery stenosis were peak systolic velocity >200 cm/s (sensitivity: 68.2%; specificity: 84.4%) to predict ≥50% stenosis and >305 cm/s (sensitivity: 57.9%; specificity: 91.4%) to predict ≥70% stenosis. Symptomatic patients with ultrasonic parameters of velocity at innominate artery ≥206 cm/s, velocity at common carotid artery ≥175 cm/s, or velocity at subclavian artery ≥200 cm/s need to be considered for further verification and whether revascularization is necessary.

Application of modified no-touch technique in rabbit arteriovenous fistula model and its effect on venous neointimal hyperplasia.

To investigate the technical advantages of a modified no-touch technique (MNTT) in constructing arteriovenous fistulas (AVF) compared to the conventional technique (CT) and assess its potential to reduce neointimal hyperplasia in the outflow vein. Forty-seven New Zealand rabbits were randomly divided into three groups: control, CT, and MNTT. Rabbits in control group were observed using ultrasound and then euthanized to obtain external jugular vein (EJV) for Hematoxylin-eosin (H-E). We established common carotid artery (CCA)-EJV AVF using MNTT in the MNTT group and the CT in the CT group. AVF patency and complications were compared between the CT and MNTT groups. Rabbits with patent AVF in both groups were observed using ultrasound 2 weeks after surgery to evaluate changes in the vessel diameter and blood flow spectrum of the AVFs. H-E staining measured the intima thickness of EJV adjacent to the anastomosis and histologic characteristics of the AVF at 2 and 4 weeks after surgery. Five rabbits died after surgery with common symptoms of sneezing, coughing, runny nose, anorexia, and diarrhea; two in the MNTT group and three in the CT group. There were significant differences in the diameter (p = 0.010) and peak systolic velocities (PSV) (p = 0.001) of EJV between the CT and MNTT groups 2 weeks after surgery. Spiral laminar flow (SLF) was observed in CCA and EJV adjacent to anastomosis in the MNTT group. Additionally, histological observations showed less venous neointimal hyperplasia in the MNTT group than in the CT group 4 weeks after surgery. The rabbit model of CCA-EJV AVF established using MNTT demonstrated fewer complications, larger vein diameters, and reduced venous neointimal hyperplasia, indicating that this maybe an ideal animal model to further investigate the application of MNTT in AVF surgery.

A Novel Sirolimus-Coated Balloon for the Treatment of Femoropopliteal Lesions: The SELUTION SFA Japan Trial

BackgroundSirolimus-coated balloons (SCB) for the treatment of femoropopliteal (FP) lesions have not been systematically studied, but initial outcomes from early studies are promising. ObjectivesThe authors sought to evaluate the safety and efficacy of the SELUTION SLR SCB, composed of proprietary microreservoir technology combining sirolimus and biodegradable polymer, when used to treat mild-to-moderate FP disease in a Japanese population. MethodsThis multicenter, prospective, single-arm study (SELUTION SFA JAPAN) enrolled 134 patients with FP disease. It was independently adjudicated by an imaging core laboratory and clinical events committee. The primary endpoint was 12-month primary patency, defined as peak systolic velocity ratio ≥2.5 by duplex ultrasound and compared against a prespecified performance goal of 60% based on established angioplasty data. ResultsThe mean age was 73.8 ± 6.9 years, and 60.3% of patients had diabetes mellitus. The mean lesion length was 127.4 ± 59.7 mm, 17.2% were chronic total occlusions, and 47.8% involved the popliteal artery. Data on 12-month restenosis were available in 127 patients (94.8%). The 12-month primary patency rate was 87.9%, and the freedom from clinically driven target lesion revascularization (CD-TLR) was 97.0% per Kaplan-Meier estimate. The major adverse event rate was 6.7%, driven by 4 CD-TLRs and 5 deaths, none of which were related to the device or procedure. Ankle-brachial index data improved significantly from 0.73 ± 0.16 at baseline to 0.96 ± 0.14 at 30 days postprocedure and was sustained through 12 months (0.94 ± 0.13). ConclusionsThe SELUTION SFA JAPAN trial demonstrated that a novel SELUTION SCB is a safe and effective treatment option for FP disease in symptomatic patients.

Cerebrovascular Effects of Sildenafil in Small Vessel Disease: The OxHARP Trial.

Vascular cognitive impairment due to cerebral small vessel disease is associated with cerebral pulsatility, white matter hypoperfusion, and reduced cerebrovascular reactivity (CVR), and is potentially improved by endothelium-targeted drugs such as cilostazol. Whether sildenafil, a phosphodiesterase-5 inhibitor, improves cerebrovascular dysfunction is unknown. OxHARP trial (Oxford Haemodynamic Adaptation to Reduce Pulsatility) was a double-blind, randomized, placebo-controlled, 3-way crossover trial after nonembolic cerebrovascular events with mild-moderate white matter hyperintensities (WMH), the most prevalent manifestation of cerebral small vessel disease. The primary outcome assessed the superiority of 3 weeks of sildenafil 50 mg thrice daily versus placebo (mixed-effect linear models) on middle cerebral artery pulsatility, derived from peak systolic and end-diastolic velocities (transcranial ultrasound), with noninferiority to cilostazol 100 mg twice daily. Secondary end points included the following: cerebrovascular reactivity during inhalation of air, 4% and 6% CO2 on transcranial ultrasound (transcranial ultrasound-CVR); blood oxygen-level dependent-magnetic resonance imaging within WMH (CVR-WMH) and normal-appearing white matter (CVR-normal-appearing white matter); cerebral perfusion by arterial spin labeling (magnetic resonance imaging pseudocontinuous arterial spin labeling); and resistance by cerebrovascular conductance. Adverse effects were compared by Cochran Q. In 65/75 (87%) patients (median, 70 years;79% male) with valid primary outcome data, cerebral pulsatility was unchanged on sildenafil versus placebo (0.02, -0.01 to 0.05; P=0.18), or versus cilostazol (-0.01, -0.04 to 0.02; P=0.36), despite increased blood flow (∆ peak systolic velocity, 6.3 cm/s, 3.5-9.07; P<0.001; ∆ end-diastolic velocity, 1.98, 0.66-3.29; P=0.004). Secondary outcomes improved on sildenafil versus placebo for CVR-transcranial ultrasound (0.83 cm/s per mm Hg, 0.23-1.42; P=0.007), CVR-WMH (0.07, 0-0.14; P=0.043), CVR-normal-appearing white matter (0.06, 0.00-0.12; P=0.048), perfusion (WMH: 1.82 mL/100 g per minute, 0.5-3.15; P=0.008; and normal-appearing white matter, 2.12, 0.66-3.6; P=0.006) and cerebrovascular resistance (sildenafil-placebo: 0.08, 0.05-0.10; P=4.9×10-8; cilostazol-placebo, 0.06, 0.03-0.09; P=5.1×10-5). Both drugs increased headaches (P=1.1×10-4), while cilostazol increased moderate-severe diarrhea (P=0.013). Sildenafil did not reduce pulsatility but increased cerebrovascular reactivity and perfusion. Sildenafil merits further study to determine whether it prevents the clinical sequelae of small vessel disease. URL: https://www.clinicaltrials.gov/study/NCT03855332; Unique identifier: NCT03855332.

Association of maternal serum vitamin D level with fetal pulmonary artery Doppler indices and neonatal respiratory distress syndrome.

Respiratory distress syndrome (RDS) is potentially fatal in infants. The present study investigated the association of maternal serum vitamin D level with fetal pulmonary artery Doppler indices and neonatal RDS. This cross-sectional-analytical study was conducted on 260 mothers admitted for delivery. The maternal serum 25-hydroxyvitamin D level was measured and fetal main pulmonary artery Doppler indices were evaluated. The neonate's weight, apgar score, RDS, Umbilical cord arterial pH and neonatal intensive care unit admission were recorded. There was a significant relationship between RDS and the low level of vitamin D in the mother's serum. Mothers with low vitamin D had higher fetal pulmonary artery pulsatility index (PI) and peak systolic velocity (PSV) and lower acceleration time (AT) to ejection time (ET) ratio. Also, in neonates with RDS, pulmonary artery PI was higher, and PSV and the ratio of AT to ET were significantly lower than neonates without RDS. Neonates with lower one and 5-min apgar scores were born from mothers with lower vitamin D levels. Serum levels of vitamin D in pregnant mothers as well as fetal pulmonary artery Doppler indices are correlated to RDS. There is a significant relationship between the serum level of vitamin D in pregnant mothers and fetal pulmonary artery Doppler indices.

Ophthalmic artery Doppler in women with hypertensive disorders of pregnancy: relationship to blood pressure control and renal dysfunction at 6-9 weeks postnatally.

To examine the postnatal course of ophthalmic artery (OA) Doppler in women with hypertensive disorders of pregnancy (HDP) and to evaluate the correlation between OA Doppler parameters and poor postnatal blood pressure control and renal dysfunction at 2-3 weeks and 6-9 weeks postnatally. This was a prospective cohort study of women with a singleton pregnancy and HDP seen at a tertiary pregnancy hypertension clinic between 2019 and 2021. Three visits were included: Visit 1, the last visit to the antenatal hypertension clinic within 2 weeks prior to delivery; Visit 2, at 2-3 weeks postnatally; and Visit 3, at 6-9 weeks postnatally. At each visit, maternal demographic characteristics, medical history, blood pressure and OA Doppler were obtained. In addition, fetal growth and fetal Dopplers were examined antenatally and, at 6-9 weeks postnatally, estimated glomerular filtration rate and proteinuria were quantified. Study participants were divided into four hypertension groups, according to longitudinal changes in blood pressure at the three visits. For the postnatal visits, hypertension was defined as systolic blood pressure (SBP) ≥ 140 mmHg and/or diastolic blood pressure (DBP) ≥ 90 mmHg in the absence of antihypertensive medication, and SBP ≥ 130 mmHg and/or DBP ≥ 80 mmHg whilst taking antihypertensives. Group 1 was hypertensive at all three visits; Group 2 was hypertensive at Visits 1 and 2 but normotensive at Visit 3; Group 3 was hypertensive at Visits 1 and 3 but normotensive at Visit 2; and Group 4 was hypertensive at Visit 1 but normotensive at Visits 2 and 3. The longitudinal changes in mean arterial pressure (MAP), peak systolic velocity (PSV) 1, PSV2 and the ratio of PSV2/PSV1 over the three timepoints were examined by a repeated-measures, multilevel, linear mixed-effects analysis, controlling for maternal age, weight at presentation and use of antihypertensive medication. In addition, we examined the longitudinal change in OA Doppler parameters in women with different degrees of postnatal blood pressure control and in those with and those without renal dysfunction at 6-9 weeks postnatally. A total of 108 women were recruited to the study, of whom 86 had new-onset hypertension and 22 had chronic hypertension. When controlling for maternal age, weight at presentation and use of antihypertensive medication, a significant decline in log10 MAP (P < 0.001), log10 PSV1 (P < 0.001) and log10 PSV2 (P = 0.01) was seen between Visits 1 and 3. Log10 PSVR did not change with time. When assessing OA Doppler against hypertension group, log10 PSV1 and log10 PSV2 did not differ between the hypertension groups, whilst Group 4 had a lower log10 PSVR compared with Group 1 (P < 0.01), Group 2 (P = 0.03) and Group 3 (P < 0.01). At 6-9 weeks postnatally, log10 PSVR was lower in those without compared to those with renal dysfunction (-0.021, P = 0.01), whilst log10 MAP, log10 PSV1 and log10 PSV2 values did not differ. Log10 PSVR did not change with time and remained at -0.12 (95% CI, -0.13 to -0.11) across the three visits. In women with HDP, the OA-PSVR was significantly higher in those with labile or persistently raised blood pressure postnatally compared to women whose blood pressure normalized. Similarly, the OA-PSVR at 6-9 weeks postnatally was significantly higher in women with renal dysfunction vs those without dysfunction. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Effect of Trunk Posture on Peak Systolic Flow Velocity, Pulsatility Index, and Rate of Perceived Exertion of Common Carotid Artery during Recumbent Cycle Exercise

Effect of Trunk Posture on Peak Systolic Flow Velocity, Pulsatility Index, and Rate of Perceived Exertion of Common Carotid Artery during Recumbent Cycle Exercise

Splenic Artery Doppler Waveforms in Gestational Diabetes and Association with Fetal Pancreas: A Prospective Case-Control Study

Introduction: This study evaluated fetal pancreas size and echogenicity, and splenic artery (SA) waveforms in pregnant women with gestational diabetes mellitus (GDM). Methods: This prospective case-control study was performed from October 2022 to November 2023 and included 124 pregnant women (62 with GDM and 62 controls). Pancreatic circumference, pancreatic echogenicity, umbilical artery Doppler measurements (systolic/diastolic ratio [S/D] and pulsatility index [PI]), SA Doppler measurements (S/D, PI, peak systolic velocity [PSV], time-averaged maximum velocity, and pressure gradient [PG] mean and maximum) values were compared between the GDM and control groups. Results: The mean pancreatic circumference was higher and grade 2/3 echogenicity was more common in the GDM group, while grade 1 echogenicity was more common in the control group (p < 0.001 and p < 0.001, respectively). SA S/D and PI measurements were significantly higher in the GDM group than in the control group (p < 0.001 and p = 0.001, respectively). Moreover, PGmax was significantly higher in the GDM group than in the control group (p = 0.038). Pancreatic circumference was positively correlated with SA PSV (p = 0.004). Additionally, pancreatic circumference was positively correlated with PGmean and PGmax (p = 0.010 and p = 0.016, respectively). The increase in pancreas echogenicity was positively correlated with SA S/D and PI measurements (p = 0.007 and p = 0.002, respectively). PGmax was also positively correlated with increased pancreas echogenicity (p = 0.023). Conclusion: This study showed that fetal pancreas size and echogenicity were significantly higher in pregnant women with GDM than in controls. SA Doppler waveforms were consistent with an increase in vascular resistance associated with elevations of both S/D and PI in the GDM group.

The effect of fetal renal artery Doppler ultrasound on neonatal outcomes in fetuses with ureteropelvic junction type obstruction

Objective: Fetal urinary tract dilatation (UTD) is one of the common fetal problems with remarkable difficulties in diagnosis and management in the antenatal and postnatal periods. This study aimed to determine the value of Doppler ultrasound assessment of the renal arteries in fetuses with ureteropelvic junction type hydronephrosis (UPJO) for the prediction of neonatal outcomes of infants. Materials and Methods: Fetal renal artery Doppler values were evaluated in pregnant women between 28-32 weeks. Measurements were taken for Doppler values and the fetal obstruction and were classified through the utilization of UTD classification. Based on postnatal ultrasound, these infants were grouped by UTD classification. Results: There was a statistically significant difference between the left renal artery Systolic/Diastolic (S/D) Ratio and bilateral renal artery Peak Systolic Velocity (PSV) values of the control and patient groups, (p&amp;lt;0.05). PSV values were higher in the patient group. The difference between the pulsality index, resistive index, and right renal artery S/D values of the control and patient groups was not statistically significant (p&amp;gt;0.05). Conclusion: Fetal renal artery Doppler is not effective in predicting the degree of hydronephrosis and renal damage in postnatal follow-up of fetuses with a diagnosis of UPJO.

Posterior Tibial Artery Blood Flow Velocity Is Increased in Patients with Plantar Heel Pain.

Background/Objectives: This study aimed to investigate the relationship between posterior tibial artery blood flow velocity and plantar heel pain (PHP). Methods: The PHP group comprised patients diagnosed with plantar fasciitis with plantar heel pain during gait, and the control group comprised healthy participants without plantar heel pain. The peak systolic velocity of the posterior tibial artery was measured using ultrasonography; it was measured three times on each side, and the mean value was calculated. Receiver operating characteristic curve analysis was performed to calculate the peak systolic velocity cutoff value for plantar heel pain. Results: 23 patients (age 58.0 ± 16.5 years; 13 males and 10 females) and 23 healthy participants (age 51.3 ± 17.3 years; 10 males and 13 females) formed the PHP and control groups, respectively. Peak systolic velocity on the affected side was significantly greater in the PHP group (44.1 ± 13.1 cm/s) than in the control group (32.7 ± 5.9 cm/s). No significant difference was observed between the left and right sides in the PHP (7.1 ± 9.8 cm/s) and control (3.7 ± 3.0 cm/s) groups. A cutoff value of 38.2 cm/s was observed on the affected side. Conclusions: We quantified the increase in posterior tibial artery blood flow velocity in patients with plantar heel pain. Peak systolic velocity measurements can aid in quantitatively evaluating these patients. This study was registered as a clinical trial (UMIN000046875) on 1 October 2021.

Hemodynamic parameters and diabetes mellitus in community-dwelling middle-aged adults and elders: a community-based study

Hemodynamic parameters have been correlated with stroke, hypertension, and arterial stenosis. While only a few small studies have examined the link between hemodynamics and diabetes mellitus (DM). This case-control study enrolled 417 DM patients and 3475 non-DM controls from a community-based cohort. Peak systolic velocity (PSV), end-diastolic velocity (EDV), blood flow velocity (MFV), pulsatility index (PI), and the resistance index (RI) of the common carotid arteries were measured by color Doppler ultrasonography. Generalized linear regression analyses showed that as compared to the non-DM controls, the age-sex-adjusted means of PSV, EDV, and MFV were − 3.28 cm/sec, − 1.94 cm/sec, and − 2.38 cm/sec, respectively, lower and the age-sex-adjusted means of RI and PI were 0.013 and 0.0061, respectively, higher for the DM cases (all p-values < 0.0005). As compared to the lowest quartiles, the multivariable-adjusted ORs of DM for the highest quartiles of PSV, EDV, MFV, RI, and PI were 0.59 (95% confidence interval [CI] 0.41–0.83), 0.45 (95% CI 0.31–0.66), 0.53 (95% CI 0.37–0.77), 1.61 (95% CI 1.15–2.25), and 1.58 (95% CI 1.12–2.23), respectively. More importantly, the additions of EDV significantly improved the predictabilities of the regression models on DM. As compared to the model contained conventional CVD risk factors alone, the area under the receiver operating curve (AUROC) increased by 1.00% (95% CI 0.29–1.73%; p = 0.0059) and 0.80% (95% CI 0.15–1.46%; p = 0.017) for models that added EDV in continuous and quartile scales, respectively. Additionally, the additions of PSV and MFV also significantly improved the predictabilities of the regression models (all 0.01 < p-value < 0.05). This study reveals a significant correlation between DM and altered hemodynamic parameters. Understanding this relationship could help identify individuals at higher risk of DM and facilitate targeted preventive strategies to reduce cardiovascular complications in DM patients.

Premature newborns with intraventricular hemorrhage do not have vasospasm pattern by cranial Doppler ultrasound: A pilot study.

Preterm neonates are at risk for neurodevelopmental impairment, especially those with intraventricular hemorrhage (IVH). Cerebral vasospasm (VSP) is a common complication after subarachnoid hemorrhage (SAH) in adult population, but it is unknown if preterm neonates with IVH may develop it. We prospectively enrolled premature newborns < 32weeks with IVH and without IVH. All patients received serial transcranial sonography through the temporal window of the middle cerebral artery, anterior cerebral artery, posterior cerebral artery, and the internal carotid artery with transcranial Doppler sonography days 2, 4, and 10 of life. Cerebral blood velocities (CBFVs) were measured including median velocity flow (MV), peak systolic velocity (PSV), and maximum end-diastolic velocity (EDV). Resistance index and pulsatility index were calculated. VSP was defined as an increase of 50% in the baseline velocity per day and/or a Lindegaard ratio higher than 3. Fifty subjects were enrolled. None of the patients with IVH showed elevation of MV or a Lindegaard ratio > 3. There were no differences between IVH and without IVH groups regarding resistance index and pulsatility index. Conclusion: Preterm infants with IVH do not present a pattern of VSP analyzed by Doppler transcranial ultrasound in this pilot study. What is Known: • In adult population with subarachnoid hemorrhage the most treatable cause of cerebral ischemia is due cerebral vasospasm but is unknown if premature newborn may have vasospasm due the extravasation of blood in the context of intraventricular hemorrhage What is New: •In this pilot study we did not find in premature newborn with intraventricular hemorrhage signs of vasoespam measured by transcranial color doppler ultrasound.

#2169 Transplant renal artery stenosis in recipients with resistant arterial hypertension

Abstract Background and Aims Transplant Renal Artery Stenosis (TRAS) is a vascular complication after kidney transplantation. It worsens the prognosis of the graft and the patient's life. The aim was to study the incidence of TRAS as a cause of resistant arterial hypertension in kidney transplant recipients in the Republic of Belarus and the efficiency of its endovascular treatment. Method The study included 187 kidney transplant recipients. Blood pressure of 72 (38.5%) patients was less than 130/80 mmHg without taking antihypertensive drugs. Arterial hypertension was diagnosed in 115 (61.5%) recipients. The study included clinical, laboratory and instrumental methods (24-hour blood pressure monitoring, Doppler ultrasound, graft scintigraphy with captopril). Results 31 (16.6%) recipients needed to take one antihypertensive drug, 43 (23.0%)—2 drugs, 41 (21.9%)—3 or more. 17 (9.1%) recipients did not have target blood pressure correction while taking more than 4 antihypertensive drugs. There was decreased blood flow in the graft artery with a peak systolic velocity &amp;gt; 200 cm/s in 14 (7.5%) cases. These patients were submitted to the graft nephroscintigraphy with caplopril where 8 grafts (4.3%) were diagnosed signs of TRAS. These recipients were submitted to the renal angiography with the injection of 150 (100; 200) ml of contrast agent. 5 (2.7%) recipients were diagnosed with hemodynamically significant TRAS of more than 70 (65; 75) % and received percutaneous transluminal angioplasty and stenting. All these patients had a decrease of glomerular filtration rate and resistant arterial hypertension before operation. The average age of the patients with TRAS was 57.4 ± 11.0 years, the period after transplantation was 11 ± 3 months. Their blood tests did not show dyslipidemia, but 4 out of 5 cases had diabetes mellitus. Their postoperative period had no complications. The patient was placed on dual antiplatelet therapy with aspirin and clopidogrel. There was an increase in glomerular filtration rate by 27 ± 7 ml/min/1.73 m2 and a decrease in systolic blood pressure by 40 (40; 45) mm Hg in the early postoperative period. Graft artery stenting allowed reducing the number of antihypertensive drugs to one tablet in 4 out of 5 patients. Conclusion Transplant Renal Artery Stenosis is a rare but significant complication of the late postoperative period that may cause resistant hypertension in kidney transplant recipients. Timely identification and stenting of the graft artery improves the graft functioning and reduces blood pressure.

Correlation and risk factors of peripheral and cervicocephalic arterial atherosclerosis in patients with ischemic cerebrovascular disease

Patients with ischemic cerebrovascular disease (ICVD) frequently develop concomitant peripheral artery disease (PAD) or renal artery stenosis (RAS), and multiterritorial atherosclerotic patients usually have a worse prognosis. We aimed to evaluate the status of peripheral atherosclerosis (AS) and cervicocephalic AS (CAS) in ICVD patients with AS, their correlation, and related risk factors contributing to coexisting cervicocephalic-peripheral AS (CPAS). Based on the severity and extent of AS evaluated by computed tomography angiography and ultrasound, the degree of AS was triple categorized to assess the correlation between CAS and PAD/RAS. CAS and PAD/RAS were defined as the most severe stenosis being ≥ 50% luminal diameter in cervicocephalic or lower limb arteries, and a peak systolic velocity at the turbulent site being ≥ 180 cm/s in the renal artery. Among 403 patients with symptom onset within 30 days, CAS, PAD, and RAS occurrence rates were 68.7%, 25.3%, and 9.9%, respectively. PAD was independently associated with the degree of extracranial and intracranial CAS (p = 0.042, OR = 1.428, 95% CI 1.014–2.012; p = 0.002, OR = 1.680, 95% CI 1.206–2.339), while RAS was independently associated with the degree of extracranial CAS (p = 0.001, OR = 2.880, 95% CI 1.556–5.329). Independent CPAS risk factors included an ischemic stroke history (p = 0.033), increased age (p < 0.01), as well as elevated fibrinogen (p = 0.021) and D-dimer levels (p = 0.019). In conclusion, the occurrence rates of RAS and PAD in ICVD patients with AS is relatively high, and with the severity of RAS or PAD increase, the severity of CAS also increase. Strengthening the evaluation of peripheral AS and controlling elevated fibrinogen might be crucial for preventing and delaying the progression of multiterritorial AS in ICVD patients with AS, thereby improving risk stratification and promoting more effective prevention and treatment strategies.

Transcranial volumetric imaging using a conformal ultrasound patch.

Accurate and continuous monitoring of cerebral blood flow is valuable for clinical neurocritical care and fundamental neurovascular research. Transcranial Doppler (TCD) ultrasonography is a widely used non-invasive method for evaluating cerebral blood flow1, but the conventional rigid design severely limits the measurement accuracy of the complex three-dimensional (3D) vascular networks and the practicality for prolonged recording2. Here we report a conformal ultrasound patch for hands-free volumetric imaging and continuous monitoring of cerebral blood flow. The 2 MHz ultrasound waves reduce the attenuation and phase aberration caused by the skull, and the copper mesh shielding layer provides conformal contact to the skin while improving the signal-to-noise ratio by 5 dB. Ultrafast ultrasound imaging based on diverging waves can accurately render the circle of Willis in 3D and minimize human errors during examinations. Focused ultrasound waves allow the recording of blood flow spectra at selected locations continuously. The high accuracy of the conformal ultrasound patch was confirmed in comparison with a conventional TCD probe on 36 participants, showing a mean difference and standard deviation of difference as -1.51 ± 4.34 cm s-1, -0.84 ± 3.06 cm s-1 and -0.50 ± 2.55 cm s-1 for peak systolic velocity, mean flow velocity, and end diastolic velocity, respectively. The measurement success rate was 70.6%, compared with 75.3% for a conventional TCD probe. Furthermore, we demonstrate continuous blood flow spectra during different interventions and identify cascades of intracranial B waves during drowsiness within 4 h of recording.

Hepatic arterial buffer response in monochorionic twins with selective fetal growth restriction.

Monochorionic twins (MC) have higher risk ofperinatal morbi-mortality compared to singletons and dichorionic twins (DC). Selective fetal growth restriction (sFGR) increases the chances of adverse outcome. Hepatic arterial buffer response (HABR) is an important mechanism for maintaining liver perfusion. We hypothesised that HABR is active in monochorionic diamniotic twins (MCDA) with sFGR where restricted fetus may have liver hypoperfusion. The objective of this study is to test whether the HAV-ratio is diminished in pregnancies affected by selective fetal growth restriction pointing to activation of HABR in the growth-restricted fetus. sFGR was defined according to a consensus definition. Hepatic artery (HA) peak systolic velocity (PSV) was measured and its correlation with fetal Dopplers and pregnancy characteristics were determined. A ratio using HA-PSV (HAV-ratio) was calculated and its association with sFGR was established. Further analysis of HA-PSV was performed comparing z-scores between normal and growth restricted fetuses. We included 202 MCDA pregnancies, 160 (79 %) normal and 42 (21 %) with sFGR. HAV-ratio was significant different between groups. The mean HAV-ratio was 1.01 (±0.20) for normal twins and 0.77 (±0.25) for sFGR. Furthermore, HA-PSV z-scores was significant increased in in growth-restricted fetus (0.94±1.45), while in normal fetuses was-0.16 (±0.97). Our findings demonstrate that, in pregnancies with sFGR, HAV-ratio is significantly lower than in normal MCDA pregnancies. The lower HAV-ratio is due to an increase in HA PSV in the growth restricted fetus. This observation indicates an activation of HABR in the small fetus.

The evaluation value of intracranial magnetic resonance angiography combined with carotid ultrasound in cerebral infarction.

To explore the evaluation value of intracranial magnetic resonance angiography (MRA) combined with carotid ultrasound (CU) in patients with cerebral infarction (CI). A retrospective analysis was conducted on 122 patients with CI who underwent intracranial MRA combined with CU examination in Shengzhou People's Hospital from January 2021 to October 2022. Vascular stenosis rate and CU parameters of patients with different degrees of nerve damage (ND) and size of CI lesion were analyzed. The rate of vascular stenosis and ultrasound parameters significantly varied between patients with different degrees of ND and different sizes of CI lesion. Spearman test showed a significant positive correlation between vascular stenosis, pulsatile index (PI), and resistance index (RI) with the degree of ND and the size of CI lesions in patients. There was a significant negative correlation between peak systolic velocity (PSV) and end-diastolic velocity (EDV) and the degree of ND and the size of CI lesions (P<0.05). Intracranial MRA combined with CU can clarify the vascular stenosis and hemodynamic characteristics of patients with CI, and the combined approach closely correlates with the characteristics of CI, which can be used for disease assessment.