Arterial Velocity Research Articles

Serum folic acid: an effective indicator for arteriogenic erectile dysfunction.

The present study is the first to explore the correlation between serum folic acid (FA) level and penile arterial peak systolic velocity (PSV) as measured via penile color Doppler ultrasonography (PDU), which directly reflects endothelial function in the penile artery. A total of 244 consecutive erectile dysfunction (ED) patients and 72 healthy controls, recruited from the Andrology department and the Healthy Physical Examination Center of our hospital, respectively, from June 2020 to April 2022, were included in the study. Serum FA was measured in ED patients and healthy controls, and PDU examinations were conducted for all eligible ED patients. The Pearson method was used to evaluate the correlation between FA levels and PDU parameters in ED patients. A receiver operating characteristic (ROC) curve analysis was also performed to calculate the sensitivity and specificity of these parameters for prediction of arteriogenic ED. After the PDU test, the average serum FA level among patients diagnosed with arteriogenic ED was 8.08 ± 2.64 ng/ml, lower than the average of 10.78 ± 2.87 ng/ml among healthy controls. There were no statistically significant inter-group differences on any basic parameters, including age, body mass index, fasting blood glucose, total cholesterol, and triglyceride. For further analysis, we divided the arteriogenic ED group into three subgroups by PSV range to compare serum FA levels among these subgroups. The mean FA levels in each of these groups were 5.97 ± 1.51ng/ml, and 8.21 ± 2.37ng/ml, and 10.55 ± 2.56ng/ml, while the corresponding PSV values were 15.75 ± 2.39cm/s, 23.53 ± 2.19cm/s, and 32.72 ± 1.64cm/s. Overall, a positive correlation between PSV and FA level was found among patients with arteriogenic ED (r=0.605, P<0.001). Furthermore, when FA level was used, with a cut-off value of 10.045 ng/ml, as a criterion to distinguish patients with arteriogenic ED from healthy controls, the area under the curve (AUC) was 0.772 (95% confidential interval: [0.696, 0.848]), for a sensitivity of 0.611 and specificity of 0.824. Serum FA level is positively correlated with PSV in ED patients, and has the ability to distinguish patients with arteriogenic ED from healthy controls. Taking these findings together, FA deficiency should be regarded as an independent risk factor for arteriogenic ED.

High posterior cerebral artery flow predicts ischemia recurrence in patients with internal carotid artery occlusion.

Recurrent stroke is a dreaded complication of symptomatic internal carotid artery occlusion (ICAO). Transcranial Duplex (TCD)-derived increased flow velocity in the ipsilateral posterior cerebral artery (PCA)-P2 segment indicates activated leptomeningeal collateral recruitment and hemodynamic impairment. Leptomeningeal collaterals are pial vascular connections between the anterior and posterior vascular territories. These secondary collateral routes are activated when primary collaterals via the Circle of Willis are insufficient. Our goal was to test the TCD parameter PCA-P2 flow for prediction of ipsilateral ischemia recurrence. We retrospectively analyzed clinical and ultrasound parameters in patients with ICAO. Together with clinical variables, we tested systolic PCA-P2 flow velocity as predictor of a recurrent ischemic event using logistic regression models. Of 111 patients, 13 showed a recurrent ischemic event within the same vascular territory. Increased flow in the ipsilateral PCA-P2 on transcranial ultrasound (median and interquartile range [IQR]: 60 cm/s [IQR 26] vs. 86 cm/s [IQR 41], p = <0.001), as well as previous transient ischemic attack (TIA) and low NIHSS were associated with ischemia recurrence. Combined into one model, accuracy of these parameters to predict recurrent ischemia was 89.2%. Our data suggest that in patients with symptomatic ICAO, flow increases in the ipsilateral PCA-P2 suggest intensified compensatory efforts when other collaterals are insufficient. Together with the clinical variables, this non-invasive and easily assessable duplex parameter detects ICAO patients at particular risk of recurrent ischemia.

Concomitant evaluation of cardiovascular and cerebrovascular controls via Geweke spectral causality to assess the propensity to postural syncope

The evaluation of propensity to postural syncope necessitates the concomitant characterization of the cardiovascular and cerebrovascular controls and a method capable of disentangling closed loop relationships and decomposing causal links in the frequency domain. We applied Geweke spectral causality (GSC) to assess cardiovascular control from heart period and systolic arterial pressure variability and cerebrovascular regulation from mean arterial pressure and mean cerebral blood velocity variability in 13 control subjects and 13 individuals prone to develop orthostatic syncope. Analysis was made at rest in supine position and during head-up tilt at 60°, well before observing presyncope signs. Two different linear model structures were compared, namely bivariate autoregressive and bivariate dynamic adjustment classes. We found that (i) GSC markers did not depend on the model structure; (ii) the concomitant assessment of cardiovascular and cerebrovascular controls was useful for a deeper comprehension of postural disturbances; (iii) orthostatic syncope appeared to be favored by the loss of a coordinated behavior between the baroreflex feedback and mechanical feedforward pathway in the frequency band typical of the baroreflex functioning during the postural challenge, and by a weak cerebral autoregulation as revealed by the increased strength of the pressure-to-flow link in the respiratory band. GSC applied to spontaneous cardiovascular and cerebrovascular oscillations is a promising tool for describing and monitoring disturbances associated with posture modification.Graphical

Evaluation of Fetal Cardiac Output and Modified Myocardial Performance Index in Pregnant Women with Idiopathic Polyhydramnios: A Case Control Study from a Tertiary Hospital.

This study aimed to investigate fetal cardiac output and myocardial performance index in pregnant women with idiopathic polyhydramnios and compare them to healthy pregnant women. Thirty patients admitted to Ankara City Hospital at 24-39 weeks of gestation with idiopathic polyhydramnios were included as the study group. Clinical characteristics, fetal cardiac output, and fetal modified myocardial performance index (Mod-MPI) were compared between the groups. The combined cardiac output (CCO), left cardiac output (LCO), right cardiac output (RCO), pulmonary artery velocity time integral (PA-VTI), and aortic VTI were statistically significantly higher in the study group (p=0.003, p=0.028, p=0.002, p=0.000, and p=0.017, respectively).The idiopathic polyhydramnios group had a significantly higher Mod-MPI and isovolumetric contraction time (ICT) and a significantly lower ejection time (ET) compared to the controls (p=000, p=0.003, and p=0.023, respectively). In the idiopathic polyhydramnios group, the aortic max (p=0.009) and aortic VTI (p=0.047) values were significantly lower and the left ventricular outflow tract isovolumetric relaxation time (LVOT-IRT) (p=0.021) was significantly higher in cases where the NICU was required. According to the ROC analysis performed in the idiopathic polyhydramnios group, the optimal cut-off values of aortic max, aortic VTI, and LVOT-IRT in the prediction of the NICU requirement were (57.5, 0.089 and 41.5, respective cut-off value) (p=0.010, p=0.048, p=0.021, respectively). Both fetal cardiac output and Mod-MPI values were altered in fetuses with idiopathic polyhydramnios.

NEUROVASCULAR COUPLING AND CEREBROVASCULAR HAEMODYNAIMCS ARE MODIFIED BY EXERCISE TRAINING STATUS AT DIFFERENT STAGES OF MATURATION DURING YOUTH.

Neurovascular coupling (NVC) is mediated via nitric oxide signalling, which is independently influenced by sex hormones and exercise training. Whether exercise training differentially modifies NVC pre- vs. post-puberty, where levels of circulating sex hormones will differ greatly within- and between-sexes, remains to be determined. Therefore, we investigated the influence of exercise training-status on resting intra-cranial haemodynamics and NVC at different stages of maturation. Posterior and middle cerebral artery velocities (PCAv and MCAv) and pulsatility index (PCAPI and MCAPI) were assessed via trans-cranial Doppler ultrasound at rest and during visual NVC stimuli. N=121 exercise-trained (males: n=32, females: n=32) and untrained (males: n=28, females: n=29) participants were characterised as pre- (males: n=33, females: n=29) or post- (males: n=27, females: n=32) peak height velocity (PHV). Exercise-trained youth demonstrated higher resting MCAv (P=0.010). Maturity- and training-status did not affect the ∆PCAv and ∆MCAv during NVC. However, pre-PHV untrained males (19.4±13.5 vs. 6.8±6.0%; P≤0.001) and females (19.3±10.8 vs. 6.4±7.1%; P≤0.001) had a higher ∆PCAPI during NVC than post-PHV untrained counterparts, while the ∆PCAPI was similar in pre- and post-PHV trained youth. Pre-PHV untrained males (19.4±13.5 vs. 7.9±6.0%; P≤0.001) and females (19.3±10.8 vs 11.1±7.3%; P=0.016) also had a larger ∆PCAPI than their pre-PHV trained counterparts during NVC, but the ∆PCAPI was similar in trained and untrained post-PHV youth. Collectively, our data indicate that exercise training elevates regional cerebral blood velocities during youth, but training-mediated adaptations in NVC are only attainable during early stages of adolescence. Therefore, childhood provides a unique opportunity for exercise-mediated adaptations in NVC.

Reliability of Ultrasound Imaging in Examining Integrity and Inflammation in the Dorsalis Pedis Artery

Assessment of small vessel inflammatory diseases such as rheumatoid vasculitis is challenging. Small arteries such as the dorsalis pedis artery (DPA) are difficult to assess for changes in the arterial wall with medical imaging. Ultrasound imaging is a viable tool for examining the integrity and inflammatory changes in the arterial wall; however, no empirical data on its reliability have been described. We measured the intra- and inter-rater reliability of ultrasound measurements across five parameters evaluating arterial integrity of the proximal DPA in participants with and without small vessel disease. We recruited 10 participants with rheumatoid arthritis and 10 healthy controls. Two sonographers using ultrasound independently measured DPA lumen diameter, artery diameter, lumen-to-arterial diameter ratio, arterial Doppler velocity and inflammatory changes in the proximal wall of the DPA. The intraclass correlation coefficient (ICC) was used to evaluate 95% confidence intervals within and between raters. Bland-Altman analyses were used to assess limits of agreement and were compared with minimal clinically important differences (MCID). Four of five selected parameters were found to have excellent intra- and inter-rater reliability within and between raters (ICC=0.903-0.996). Acceptable reliability was found for measurement of arterial blood flow velocity within raters (ICC=0.815-0.909), but not between raters (ICC=0.634). Standard mean errors in all parameters were within minimal clinically important differences. Ultrasound imaging has been found to be a reliable method of assessment of arterial integrity and inflammation of the proximal DPA in people with small vessel disease. Evaluation of arterial blood flow velocity requires cautious interpretation.

The Association of Tacrolimus Formulation on Cerebral Blood Flow and Cognitive Function.

We randomized (2:1) 30 stable KT recipients on IR tacrolimus to intervention (switch to LCP tacrolimus) and control (continue IR tacrolimus) arms. We measured CBF, CVR, and cognitive function at baseline and at 12 wk. We used ANCOVA to evaluate changes in outcome variables, with baseline values and study arm as covariates. We used descriptive statistics with mean changes in outcome variables to compare the 2 groups. Participants were 51 ± 13 y old. There was no difference in plasma tacrolimus levels at baseline and at 12 wk in the 2 arms. The changes in CBF, resting middle cerebral artery velocity, CVR, and cognitive function were more favorable in the intervention arm than in the control group. Changing IR tacrolimus to LCP tacrolimus may improve CBF, cerebrovascular dynamics, and cognitive function in KT recipients. Larger studies are needed to confirm these results.

Ultrasound assessment is useful for evaluating balloon volume of resuscitative endovascular balloon occlusion of the aorta.

Endovascular balloon occlusion of the aorta (EBOA) increases proximal arterial pressure but may also induce life-threatening ischemic complications. Although partial REBOA (P-REBOA) mitigates distal ischemia, it requires invasive monitoring of femoral artery pressure for titration. In this study, we aimed to titrate P-REBOA to prevent high-degree P-REBOA using ultrasound assessment of femoral arterial flow. Proximal (carotid) and distal (femoral) arterial pressures were recorded, and perfusion velocity of distal arterial pressures was measured by pulse wave Doppler. Systolic and diastolic peak velocities were measured among all ten pigs. Total REBOA was defined as a cessation of distal pulse pressure, and maximum balloon volume was documented. The balloon volume (BV) was titrated at 20% increments of maximum capacity to adjust the degree of P-REBOA. The distal/proximal arterial pressure gradient and the perfusion velocity of distal arterial pressures were recorded. Proximal blood pressure increased with increasing BV. Distal pressure decreased with increasing BV, and distal pressure sharply decreased by > 80% of BV. Both systolic and diastolic velocities of the distal arterial pressure decreased with increasing BV. Diastolic velocity could not be recorded when the BV of REBOA was > 80%. The diastolic peak velocity in the femoral artery disappeared when %BV was > 80%. Evaluation of the femoral artery pressure by pulse wave Doppler may predict the degree of P-REBOA without invasive arterial monitoring.

Lower systemic nitric oxide bioactivity, cerebral hypoperfusion and accelerated cognitive decline in formerly concussed retired rugby union players.

What is the central question of this study? What are the molecular, cerebrovascular and cognitive biomarkers of retired rugby union players with concussion history? What is the main finding and its importance? Retired rugby players compared with matched controls exhibited lower systemic nitric oxide bioavailability accompanied by lower middle cerebral artery velocity and mild cognitive impairment. Retired rugby players are more susceptible to accelerated cognitive decline. Following retirement from sport, the chronic consequences of prior-recurrent contact are evident and retired rugby union players may be especially prone to accelerated cognitive decline. The present study sought to integrate molecular, cerebrovascular and cognitive biomarkers in retired rugby players with concussion history. Twenty retired rugby players aged 64±5years with three (interquartile range (IQR), 3) concussions incurred over 22 (IQR, 6) years were compared to 21 sex-, age-, cardiorespiratory fitness- and education-matched controls with no prior concussion history. Concussion symptoms and severity were assessed using the Sport Concussion Assessment Tool. Plasma/serum nitric oxide (NO) metabolites (reductive ozone-based chemiluminescence), neuron specific enolase, glial fibrillary acidic protein and neurofilament light-chain (ELISA and single molecule array) were assessed. Middle cerebral artery blood velocity (MCAv, doppler ultrasound) and reactivity to hyper/hypocapnia ( / ) were assessed. Cognition was determined using the Grooved Pegboard Test and Montreal Cognitive Assessment. Players exhibited persistent neurological symptoms of concussion (U=109(41) , P=0.007), with increased severity compared to controls (U=77(41) , P<0.001). Lower total NO bioactivity (U=135(41) , P=0.049) and lower basal MCAv were apparent in players (F2,39 =9.344, P=0.004). This was accompanied by mild cognitive impairment (P=0.020, 95% CI, -3.95 to -0.34), including impaired fine-motor coordination (U=141(41) , P=0.021). Retired rugby union players with history of multiple concussions may be characterised by impaired molecular, cerebral haemodynamic and cognitive function compared to non-concussed, non-contact controls.

Using Middle Cerebral Artery Doppler Ultrasound to Predict Clinical Chorioamnionitis After Preterm Prelabor Rupture of Membranes.

In neonates, blood flow to the brain as measured by peak systolic velocity (PSV) in the middle cerebral artery (MCA) is altered in pregnancies affected by chorioamnionitis. We aim todetermine whether PSV and other measures of flow in the MCA in the fetus are altered prior to the development of clinical chorioamnionitis following preterm prelabor rupture of membranes (PPROM). This was a prospective observational study. Fifty patients from one institution were recruited after being diagnosed with PPROM between 23 weeks zero days and 33 weeks six days gestation.We performed measurements of the PSV in the fetal MCA on a weekly basis following PPROMand used the value taken closest to the time of delivery for our statistical analysis.The primary outcome assessed was clinical chorioamnionitis, and the exposure of interest was MCA PSV.Additional independent variables of interest were other Doppler measures of the MCA.Secondary outcomes included histological chorioamnionitis and other measures of neonatal health, including sepsis, days in the neonatal intensive care unit(NICU), and death. Of the 50 patients recruited to our study, eight (16%) developed clinical chorioamnionitis, similar to previously reported values in the general population.The PSV in the MCA was not significantly associated with the development of clinical chorioamnionitis. However, an elevated MCA pulsatility index (PI), a measure of resistance to flow, was associated with a higher probability of developing clinical chorioamnionitis. There does not appear to be a difference in the PSV of the MCA of fetuses in pregnancies following PPROM with impending chorioamnionitis.However, elevated PI in the MCA could be a marker of impending chorioamnionitis in PPROM. Larger studies are needed to confirm these findings.

The effects of water temperature on cerebral blood flow during aquatic exercise

PurposeRecent studies suggest that episodic increases in cerebral blood flow (CBF) may contribute to the improvement in brain health associated with exercise training. Optimising CBF during exercise may enhance this benefit. Water immersion in ~ 30–32 °C augments CBF at rest and during exercise; however, the impact of water temperature on the CBF response has not been investigated. We hypothesised that cycle ergometry in water would increase CBF compared to land-based exercise, and that warm water would attenuate the CBF benefits.MethodsEleven young heathy participants (nine males; 23.8 ± 3.1 yrs) completed 30 min of resistance-matched cycle exercise in three separate conditions; non-immersion (Land), 32 °C and 38 °C water immersion up to the level of the waist. Middle cerebral artery velocity (MCAv), blood pressure, and respiratory measures were assessed throughout the exercise bouts.ResultsCore temperature was significantly higher in the 38 °C immersion than 32 °C (+ 0.84 ± 0.24 vs + 0.04 ± 0.16, P < 0.001), whilst mean arterial pressure was lower during 38 °C exercise compared to Land (84 ± 8 vs 100 ± 14 mmHg, P < 0.001) and 32 °C (92 ± 9, P = 0.03). MCAv was higher in 32 °C immersion compared to the Land and 38 °C conditions throughout the exercise bout (68 ± 10 vs 64 ± 11 vs 62 ± 12 cm/s, P = 0.03 and P = 0.02, respectively).ConclusionOur findings suggest that cycle exercise in warm water attenuates the beneficial impact of water immersion on CBF velocity due to redistribution of blood flow to subserve thermoregulatory demand. Our findings suggest that, whilst water-based exercise can have beneficial effects on cerebrovascular function, water temperature is a key determinant of this benefit.

Subclassification of fetal growth restriction type IIa vs type IIb applied to twin-twin transfusion syndrome

Subclassification of monochorionic twins with selective fetal growth restriction (sFGR) type II into IIa vs. IIb has been proposed due to differing neonatal survival outcomes of the growth-restricted fetus after laser surgery based on preoperative Doppler findings in the middle cerebral artery (MCA) and ductus venosus (DV). There is substantial clinical overlap between sFGR and twin-twin transfusion syndrome (TTTS). To compare donor twin neonatal survival after laser surgery in cases of TTTS with concomitant donor FGR type IIa vs. IIb. This is a retrospective study of monochorionic multifetal gestations treated with laser for Stage III TTTS and concomitant donor twin FGR type II at a referral center from 2006-2021. Donor FGR type II was defined as having an estimated fetal weight (EFW) <10th percentile with persistent absent and/or reversed end diastolic velocity in the umbilical artery. Patients were then subclassified as type IIa (having normal MCA peak systolic velocities [psv] and DV Doppler waveforms) vs. type IIb (having MCA psv ≥1.5 multiples of the median and/or DV with persistent absent or reversed atrial systolic flow). We compared 30-day neonatal survival of the donor twin by FGR type IIa vs. IIb using logistic regression to adjust for relevant preoperative covariates (p<0.10 in bivariate analysis). Of 919 patients who underwent laser surgery for TTTS, 262 had Stage III donor or donor/recipient TTTS; of these, 189 (20.6%) had concomitant donor FGR type II. Twelve met exclusion criteria, yielding 177 patients (19.3%) who comprised the study cohort. Patients were subclassified as donor FGR type IIa (146 [82%]) vs. type IIb (31 [18%]). Donor neonatal survival for FGR type IIa vs. IIb was 71.2% vs. 41.9% (p=0.003). Recipient neonatal survival did not differ between the two types (p=1.000). Patients classified with TTTS and concomitant donor FGR type IIb were 66% less likely to have neonatal survival of the donor after laser surgery (adjusted OR=0.34, 95% CI 0.15-0.80; p=0.0127). The logistic regression model was adjusted for gestational age at the procedure, EFW percent discordance, and nulliparity. The c-statistic was 0.702. For patients with Stage III TTTS and concurrent donor FGR with persistent absent or reversed end diastolic velocity in the umbilical artery (i.e., FGR type II), subclassification into FGR type IIb based on elevated MCA psv and/or abnormal DV flow in the donor conveyed poorer prognosis. Although donor neonatal survival after laser surgery was lower for Stage III TTTS patients with donor FGR type IIb compared with type IIa, laser surgery for FGR type IIb in the setting of TTTS (as opposed to pure sFGR type IIb) still allows for the possibility of dual survivorship and should be offered with shared decision-making when counseling patients on management options.

Features of Ocular Blood Flow in Malignant Arterial Hypertension of Renal Origin

Color Doppler imaging allows a detailed non-invasive assessment of the state of blood flow in the retrobulbar vessels in patients with various vascular pathologies. Malignant hypertension (MH) is a clinical syndrome characterized by severe diastolic arterial hypertension (140 mm Hg or more), leading to ischemic damage to various organs — kidneys, heart, brain, eyes. Patients with MH often present with thrombotic microangiopathy (TMA), a rare life-threatening condition characterized by multiple systemic thromboses of the microvasculature.Purpose: to assess the state of blood flow in retrobulbar vessels by color Doppler imaging in TMA associated with MH.Methods: 10 patients (20 eyes) (age 43.5 ± 6.2 years) with TMA associated with MH underwent a study of the state of blood flow in the vessels of the retrobulbar space by color Doppler imaging. Qualitative and quantitative analyzes of retinal and choroidal circulation were assessed.Results. Analysis of the Doppler spectrum of blood flow in TMA associated with MH revealed a statistically significant increase in maximum systolic (Vsyst) and finale diastolic blood flow velocity (Vdiast) in the ophthalmic artery (OA), as well as Vsyst in the medial short posterior ciliary arteries (SPCA), compared with the control group (p &lt; 0.05). In 2 patients (20 %) of the study group, a significant bilateral decrease in the diastolic component of the spectrum was found up to the isoline (Vdiast = 0) and a maximum increase in the peripheral resistance index (RI = 1.0). Statistically significant correlations were found between some laboratory parameters of blood serum (hemoglobin, lactate dehydrogenase, creatinine), as well as the estimated glomerular filtration rate and hemodynamic parameters in the central retinal artery (CRA), lateral (SPCA) and OA (p &lt; 0.05).Conclusion. The results of the study of ocular hemodynamics using color Doppler imaging in TMA associated with MH are presented for the first time. TMA associated with MH is characterized by a statistically significant increase in the maximum systolic blood flow velocity in the OA and SPCA with the development of an ischemic state in the retinal and choroidal microcirculation in some patients. An increase in TMA activity in MH leads to a change in the microcirculation of the retina and choroid of an ischemic nature. An increase in blood creatinine in patients with TMA with MH is statistically significantly associated with a decrease in systolic blood flow velocity in the CRA.

Doppler ocular ultrasound in patients with type 2 diabetes mellitus

Purpose: To determine ocular blood flow parameters by Doppler ultrasound scanning in type 2 diabetic patients with different stages of diabetic retinopathy. Material and Methods: In this prospective study, forty-five patients (90 eyes) with type 2 diabetes mellitus were divided into three groups of 15 patients each: no diabetic retinopathy group (DR0), non-proliferative retinopathy (NPDR), and proliferative retinopathy (PDR) groups. Doppler indices such as systolic blood flow velocity (Vs), diastolic blood flow velocity (Vd), time-averaged maximum velocity (TAMXV), pulsatility index (PI) and resistivity index (RI) in the ophthalmic artery (OA), central retinal artery (CRA) and short posterior ciliary arteries (SPCA) were determined. ANOVA was used for quantitative comparisons between the three groups. Results: There was a significant (р less 0.05) decrease in (a) the Vs from 71.1 +- 20.6 cm/s in the DR0 group to 59.9 +- 16.7 cm/s in the NPDR group and 47.4 +- 16.4 cm/s in the PDR group, (b) Vd from 22.1 +- 6.9 cm/s to 17.0 +- 6.6 cm/s and 12.3 +- 5.9 cm/s, respectively; and (c) TAMXV from 37.2 +- 11.3 cm/s to 31.9 +- 9.1 cm/s and 25.3 +- 9.7 cm/s, respectively, and an increase in the RI from 0.69 +- 0.06 cm/s to 0.71 +- 0.09 cm/s and 0.75 +- 0.08 cm/s, respectively, in the OA. In addition, there was a significant decrease in the Vd from 9.9 +- 5.4 cm/s in the DR0 group to 8.1 +- 3.8 cm/s in the NPDR group and 5.5 +- 3.1 cm/s in the PDR group, and an increase in the PI from 1.34 +- 0.16 cm/s to 1.46 +- 0.28 cm/s and 1.54 +- 0.24 cm/s, respectively, and in the RI from 0.71 +- 0.06 cm/s to 0.75 +- 0.07 cm/s and 0.80 +- 0.05 cm/s, respectively, in the CRA. Moreover, there was a significant decrease in the Vd from 4.3 +- 1.6 cm/s in the DR0 group to 3.2 +- 2.0 cm/s in the NPDR group and 3.1 +- 2.2 cm/s in the PDR group, and an increase in the PI from 1.32 +- 0.21 cm/s to 1.37 +- 0.24 cm/s and 1.54 +- 0.26 cm/s, respectively, and in the RI from 0.76 +- 0.04 cm/s to 0.82 +- 0.06 cm/s and 0.82 +- 0.06 cm/s, respectively, in the SPCA. Conclusion: We found that the arteries examined in patients with diabetic retinopathy tended to have decreased blood flow velocities and increased resistivity and pulsatility indices, with the greatest changes observed in patients with PDR. In addition, the difference in mean values of most Doppler indices between the PDR and NPDR groups was larger than that between the NPDR and DR0 groups.

Relationship between the Central and Regional Pulse Wave Velocity in the Assessment of Arterial Stiffness Depending on Gender in the Geriatric Population.

Artery stiffness is a risk factor for cardiovascular disease (CVD). The measurement of pulse wave velocity (PWV) between the carotid artery and the femoral artery (cfPWV) is considered the gold standard in the assessment of arterial stiffness. A relationship between cfPWV and regional PWV has not been established. The aim of this study was to evaluate the influence of gender on arterial stiffness measured centrally and regionally in the geriatric population. The central PWV was assessed by a SphygmoCor XCEL, and the regional PWV was assessed by a new device through the photoplethysmographic measurement of multi-site arterial pulse wave velocity (MPPT). The study group included 118 patients (35 males and 83 females; mean age 77.2 ± 8.1 years). Men were characterized by statistically significantly higher values of cfPWV than women (cfPWV 10.52 m/s vs. 9.36 m/s; p = 0.001). In the measurement of regional PWV values using MPPT, no such relationship was found. Gender groups did not statistically differ in the distribution of atherosclerosis risk factors. cfPWV appears to be more accurate than regional PWV in assessing arterial stiffness in the geriatric population.

Hands-free continuous carotid Doppler ultrasound for detection of the pulse during cardiac arrest in a porcine model

Background/PurposePulse palpation is an unreliable method for diagnosing cardiac arrest. To address this limitation, continuous hemodynamic monitoring may be a viable solution. Therefore, we developed a novel, hands-free Doppler system, RescueDoppler, to detect the pulse continuously in the carotid artery. MethodsIn twelve pigs, we evaluated RescueDoppleŕs potential to measure blood flow velocity in three situations where pulse palpation of the carotid artery was insufficient: (1) systolic blood pressure below 60 mmHg, (2) ventricular fibrillation (VF) and (3) pulseless electrical activity (PEA). (1) Low blood pressure was induced using a Fogarty balloon catheter to occlude the inferior vena cava. (2) An implantable cardioverter-defibrillator induced VF. (3) Myocardial infarction after microembolization of the left coronary artery caused True-PEA. Invasive blood pressure was measured in the contralateral carotid artery. Time-averaged blood flow velocity (TAV) in the carotid artery was related to mean arterial pressure (MAP) in a linear mixed model. ResultsRescueDoppler identified pulsatile blood flow in 41/41 events with systolic blood pressure below 60 mmHg, with lowest blood pressure of 19 mmHg. In addition the absence of spontaneous circulation was identified in 21/21 VF events and true PEA in 2/2 events. The intraclass correlation coefficient within animals for TAV and MAP was 0.94 (95% CI. 0.85–0.98). ConclusionsIn a porcine model, RescueDoppler reliably identified pulsative blood flow with blood pressures below 60 mmHg. During VF and PEA, circulatory arrest was rapidly and accurately demonstrated. RescueDoppler could potentially replace unreliable pulse palpation during cardiac arrest and cardiopulmonary resuscitation.

Relative contributions of arterial stiffness to cardiovascular disease risk score in Chinese women in framingham and China-PAR model.

Arterial stiffness played an important role in the development of cardiovascular disease (CVD) events. The aim of this study was to verify the relative importance of arterial stiffness for different CVD risk scores in a large sample of Chinese women. We measured arterial velocity pulse index (AVI) and CVD risk scores in 2220 female participants (mean age 57 years). Framingham Risk Score (FRS), and the prediction for Atherosclerotic Cardiovascular Disease Risk in China (China-PAR) were used to estimate CVD risk, respectively. The relationships between AVI and risk scores were investigated by linear regressions and restricted cubic spline (RCS) analysis. To determine the relative importance of AVI in predicting CVD risk scores, random forest analysis was used. There was a significant positive correlation between AVI and FRS, China-PAR in all subgroup groups stratified by age, blood pressure and BMI. AVI showed higher importance in predicting CVD risk scores in FRS model, compared with these traditional risk factors. In China-PAR model, although AVI was not as predictive as SBP, it had better predictive power than many known risk factors such as lipids. Furthermore, AVI had significant J-shaped associations both with FRS and China-PAR scores. AVI was significantly associated with CVD risk score. In FRS and China-PAR model, AVI showed relatively high importance in predicting CVD risk scores. These findings may support the use of arterial stiffness measurements in CVD risk assessment.

#5555 TAKAYASU ARTERITIS IN THE TIME OF SARS-COV-2

Abstract Background and Aims SARS CoV 2 infection is characterized by pulmonary, cardiovascular, neurological and other complications. New onset hypertension after SARS Cov 2 infection was observed in various studies with an unclear mechanism. Vessel inflammation is a common finding in these patients. Case A young woman (24 years old) referred to our Unit for high blood pressure levels appeared few days after SARS COVID 2 infection. She had a positive familiar history of hypertension. A 24 hours blood pressure monitoring confirmed hypertension and the patient was treated with a beta-blocker and referred to the nephrologist. Physical examination was negative and peripheral pulses were palpable. Blood pressure was 150/90 mmHg without significative discrepancy (&amp;lt;10 mmHg) between right and left arm and between upper and lower limbs. Carotid-femoral and carotid-radial pulse wave velocity was in the upper limit of the normal range (9.8 and 8.0 m/sec respectively), renal function was preserved (serum creatinine 0.6 mg/dl, eGFR 154 ml/min) and proteinuria was 450 mg/die. C-reactive protein was 13 mg/L. Complement components C3 and C4 as well as IgG and anti-neutrophil cytoplasmic antibody (ANCA) levels were in the normal range. IgA and IgM were slightly elevated and anti-nuclear antibody (ANA) levels were 1:160. TSH was in the normal range. Patient was switched to calcium channel blockers and a screening to exclude secondary hypertension was performed. Hormonal profile showed hypersecretion of cortex and medullary adrenal gland (high renin and aldosterone, plasma and urinary cortisol, and epinephrine levels). Patient was treated with ACE inhibitor and showed an optimal blood pressure profile. Abdominal-Chest CT angiography detected no increase in adrenal gland dimension. Conversely, a left renal artery stenosis and a mild enlargement of the para-aortic tissue, suggestive of a retroperitoneal fibrosis, was described (Figure 1). A Doppler ultrasound examination confirmed a high systolic peak velocity in left renal artery and a low resistive index in the left kidney. According to the diagnosis of renal fibrosis, patient was treated with oral prednisone at a dosage of 1 mg/Kg/BW. Three months later, Doppler ultrasound and CT were materially unchanged. After a case revision and a negative evidence of inflammation at PET-FDG examination, the Takayasu Arteritis diagnosis was formulated and the patient underwent left renal artery angioplasty. Oral prednisone was tapered and methotrexate was started. One month later blood pressure and Doppler ultrasound velocimetric parameters were normalized. Conclusion This case report suggests that Takayasu arteritis may occur after SARS COVID 2 infection.

#3250 RENAL HAEMODYNAMIC PARAMETERS IN DIABETIC NEPHROPATHY

Abstract Background and Aims Diabetic nephropathy is the leading cause of chronic kidney disease in modern world. Timely diagnosis is of paramount importance, especially after the recent introduction of novel therapies. The presence of an already altered renal haemodynamic profile was investigated in all patients referred with suspected diabetic nephropathy, upon their initial presentation to our renal department. Method During the past seven years, from January 2015 to December 2022, 578 patients were referred to the Renal Department for ultrasound assessment. Additionally to their standard assessment, they underwent renal ultrasound and triplex examination. Diabetic nephropathy (DN) was diagnosed in 149 patients. A group of patients with an estimated GFR&amp;gt; 60 ml/min, without diabetic nephropathy, was randomly selected from the same pull of patients for comparison reasons (control group). Renal haemodynamics assessment, including renal arteries, aorta and intrarenal resistive indexes (RI) of both kidneys, estimated glomerular filtration rate (CKDEPI) and 24h albuminuria, were evaluated in all patients. Results The mean age of the patients was 72.5 ±10.4 vs 65.8 ±6.9 years, for the DN and control group respectively. Renal length was comparable in both groups, renal diameter of left kidney was 10.61 ±1.28 vs. 10.59 ±1.44 cm and renal diameter of right kidney was 10.53 ±1.38 vs. 9.85 ±2.89 cm for DN group and control respectively. The estimated GFR was significantly lower in the DN group, 42.1±23.6 vs. 82.7 ±11.3 ml/min (p&amp;lt;0.05). Both renal arteries presented higher velocity values in the DN group, 53.4 ±22.2 vs. 21.7 ±28.9 cm/sec (p&amp;lt;0.0001) and 52.4 ±23.9 vs. 24.8 ±32.3 (p&amp;lt;0.0001), for the left and right renal artery. DN patients showed RI values above upper normal limit of 0.70, being at the same time significantly higher compared to control group, 0.73 ±0.06 vs. 0.61 ±0.17 (p&amp;lt;0.0001) and 0.72 ±0.06 vs. 0.59 ±0.20 (p&amp;lt;0.0001), for the left and right kidney respectively. Conclusion The presence of significantly increased renal artery velocity in diabetic nephropathy patients compared to control patients has not been described earlier to the best of our knowledge. It represents a new finding that is mainly attributed to the presence of arteriopathy. Evaluation of renal haemodynamics using triplex ultrasound, represents a non – invasive, readily available, inexpensive examination. When performed at initial patient presentation, constitutes an invaluable tool, timely assisting to diagnosis and treatment of diabetic patients.

Quick Assessment of the Lower Limit of Cerebral Autoregulation Using Transcranial Doppler during Cardiopulmonary Bypass in Cardiac Surgery: A Feasibility Study.

During cardiac surgery, maintaining a mean arterial pressure (MAP) within the range of cerebral autoregulation (CA) may prevent postoperative morbidity. The lower limit of cerebral autoregulation (LLA) can be determined using the mean velocity index (Mx). The standard Mx is averaged over a ten second period ( ) while using a two second averaging period ( ) is faster and may record more rapid variations in LLA. The objective of this study is to compare a quick determination of LLA (qLLA) using with the reference LLA (rLLA) using . Single center, retrospective, observational study. Patients undergoing cardiac surgery with cardiopulmonary bypass. From January 2020 to April 2021, perioperative transcranial doppler measuring cerebral artery velocity was placed on cardiac surgery patients in order to correlate with continuous MAP values. Calculation of each patient's Mx was manually determined after the surgery and qLLA and rLLA were then calculated using a threshold value of Mx 0.4. 55 patients were included. qLLA was found in 78% of the cases versus 47% for rLLA. Despite a -3 mmHg mean bias, limits of agreement were large [-19 mmHg (95% CI: -13; -25), and +13 mmHg (95% CI: +6; +19)]. There was an important interobserver variability (kappa rLLA = 0.46; 95% CI: 0.24-0.66; and Kappa qLLA = 0.36; 95% CI: 0.20-0.52). Calculation of qLLA is feasible. However, the large limits of agreement and significant interobserver variability prevent any clinical utility or interchangeability with rLLA.