The Correlation between Carotid Artery Corrected Flow Time and Velocity Time Integral during Central Blood Volume Loss and Resuscitation

Background

Doppler ultrasound of the common carotid artery is used to infer central hemodynamics. For example, change in the common carotid artery corrected flow time (ccFT) and velocity time integral (VTI) are proposed surrogates of changing stroke volume. However, conflicting data exist which may be due to inadequate beat sample size and measurement variability - both intrinsic to handheld systems. In this brief communication, we determined the correlation between changing ccFT and carotid VTI during progressively severe central blood volume loss and resuscitation.

Methods

Measurements were obtained through a novel, wireless, wearable Doppler ultrasound system. Sixteen participants (ages of 18-40 years with no previous medical history) were studied across 25 lower body-negative pressure protocols. Relationships were assessed using repeated-measures correlation regression models.

Results

In total, 33,110 cardiac cycles comprise this analysis; repeated-measures correlation showed a strong, linear relationship between ccFT and VTI. The strength of the ccFT-VTI relationship was dependent on the number of consecutively averaged cardiac cycles (R1 cycle = 0.70, R2 cycles = 0.74, and R10 cycles = 0.81).

Conclusions

These results positively support future clinical investigations employing common carotid artery Doppler as a surrogate for central hemodynamics.

Risk of adverse perinatal outcomes in pregnancies with "small" fetuses not meeting Delphi consensus criteria for fetal growth restriction

BACKGROUND

Previous research endeavors examining the association between clinical characteristics, sonographic indices, and the risk of adverse perinatal outcomes in pregnancies complicated by fetal growth restriction have been hampered by a lack of agreement regarding its definition. In 2016, a consensus definition was reached by an international panel of experts via the Delphi procedure, but as it currently stands, this has not been endorsed by all professional organizations.

OBJECTIVE

This study aimed to assess whether an independent association exists between estimated fetal weight and/or abdominal circumference of <10th percentile and adverse perinatal outcomes when consensus criteria for growth restriction are not met.

STUDY DESIGN

Data were derived from a passive prospective cohort of singleton nonanomalous pregnancies at a single academic tertiary care institution (2010-2022) that fell into 3 groups: (1) consecutive fetuses that met the Delphi criteria for fetal growth restriction, (2) small-for-gestational-age fetuses that failed to meet the consensus criteria, and (3) fetuses with birthweights of 20th to 80th percentile randomly selected as an appropriately grown (appropriate-for-gestational-age) comparator group. This nested case-control study used 1:1 propensity score matching to adjust for confounders among the 3 groups: fetal growth restriction cases, small-for-gestational-age cases, and controls. Our primary outcome was a composite: perinatal demise, 5-minute Apgar score of <7, cord pH of ≤7.10, or base excess of ≥12. Pregnancy characteristics with a P value of <.2 on univariate analyses were considered for incorporation into a multivariable model along with fetal growth restriction and small-for-gestational-age to evaluate which outcomes were independently predictive of adverse perinatal outcomes.

RESULTS

Overall, 2866 pregnancies met the inclusion criteria. After propensity score matching, there were 2186 matched pairs, including 511 (23%), 1093 (50%), and 582 (27%) patients in the small-for-gestational-age, appropriate-for-gestational-age, and fetal growth restriction groups, respectively. Moreover, 210 pregnancies (10%) were complicated by adverse perinatal outcomes. None of the pregnancies with small-for-gestational-age OR appropriate-for-gestational-age fetuses resulted in perinatal demise. Twenty-three of 511 patients (5%) in the small-for-gestational-age group had adverse outcomes based on 5-minute Apgar scores and/or cord gas results compared with 77 of 1093 patients (7%) in the appropriate-for-gestational-age group (odds ratio, 0.62; 95% confidence interval, 0.39-1.00). Furthermore, 110 of 582 patients (19%) with fetal growth restriction that met the consensus criteria had adverse outcomes (odds ratio, 3.08; 95% confidence interval, 2.25-4.20), including 34 patients with perinatal demise or death before discharge. Factors independently associated with increased odds of adverse outcomes included chronic hypertension, hypertensive disorders of pregnancy, and early-onset fetal growth restriction. Small-for-gestational age was not associated with the primary outcome after adjustment for 6 other factors included in a model predicting adverse perinatal outcomes. The bias-corrected bootstrapped area under the receiver operating characteristic curve for the model was 0.72 (95% confidence interval, 0.66-0.74). The bias-corrected bootstrapped area under the receiver operating characteristic curve for a 7-factor model predicting adverse perinatal outcomes was 0.72 (95% confidence interval, 0.66-0.74).

CONCLUSION

This study found no evidence that fetuses with an estimated fetal weight and/or abdominal circumference of 3rd to 9th percentile that fail to meet the consensus criteria for fetal growth restriction (based on Doppler waveforms and/or growth velocity of ≥32 weeks) are at increased risk of adverse outcomes. Although the growth of these fetuses should be monitored closely to rule out evolving growth restriction, most cases are healthy constitutionally small fetuses. The management of these fetuses in the same manner as those with suspected pathologic growth restriction may result in unnecessary antenatal testing and increase the risk of iatrogenic complications resulting from preterm or early term delivery of small fetuses that are at relatively low risk of adverse perinatal outcomes.

Transient ischemic attack due to dynamic evolution of carotid artery web

Carotid artery web (CaW) is a rare focal fibromuscular dysplasia, which is an underappreciated risk factor for transient ischemic attack. This case illustrates the dynamic evolution of secondary thrombus and plaque in CaW, and the importance of carotid doppler ultrasound in early detection and follow-up.

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

Background/Purpose

Pulse 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.

Methods

In 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.

Results

RescueDoppler 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).

Conclusions

In 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.

Contrast-Enhanced Ultrasound and High Sensitive Doppler for Monitoring Outcomes of Uterine Artery Embolization

RATIONALE AND OBJECTIVES

To monitor fibroid microvascularity using contrast-enhanced ultrasound (CEUS) and a new high-sensitive Doppler mode (SMI) for assessment of uterine artery embolization (UAE) outcomes.

MATERIALS AND METHODS

Forty women with symptomatic uterine fibroids scheduled for UAE were enrolled in this Institutional Review Board-approved study. Subjects underwent three examinations (day 0, 15, and 90 post-UAE) with Color Doppler (CDI), power Doppler (PDI), color and monochrome SMI (cSMI and mSMI), and CEUS imaging of the fibroids. Clips were assessed by two radiologists classifying fibroids based on their vascularity. Fibroid fractional vascularity (FV; % of enhanced pixels within the fibroid) and flow intensity (as mean brightness level of the enhanced pixels) were quantified. Results were analyzed using repeated measures ANOVA and nonparametric Wilcoxon sign rank tests. Inter-reader agreement was assessed with κ-values.

RESULTS

There was overall agreement between readers for all imaging modalities and examination times (P = .25; κ = 0.70). The FV analysis showed statistically significant differences between CEUS and the Doppler imaging modes (CDI, PDI, cSMI, and mSMI) for the three examination times were compared (P < .0001). The comparison using CDI, PDI, and cSMI showed no statistically significant difference (P = .53). The flow intensity analysis comparison between the Doppler imaging modes (CDI, PDI, cSMI and mSMI) and examination times showed statistically significant differences between all the Doppler imaging modalities (P = .02), except for the 90days post-UAE (P = .34). When the comparison was made for CDI, PDI, and cSMI there was no statistically significant differences (P < .47).

CONCLUSION

CEUS and SMI can accurately evaluate fibroid microvascularity, and therefore, can be a noninvasive and accurate method for monitoring outcomes following UAE treatment.

[Efficacy of Sildenafil oral spray for the treatment of erectile dysfunction in patients with type 2 diabetes mellitus and prediabetes]

AIM

To evaluate the results of using Sildenafil in the form of an oral spray (Gent) for the treatment of erectile dysfunction (ED) in men with type 2 diabetes mellitus (DM) and prediabetes.

MATERIAL AND METHODS

A total of 60 patients were divided into two groups of 30 people. The group 1 included patients with prediabetes, while group 2 consisted of patients with type 2 DM. All men had proven ED. The severity of ED was assessed using the International Index of Erectile Function (IIEF-5). To assess the state of penile blood flow, all patients underwent Doppler ultrasound before and after treatment. Patients with prediabetes used Sildenafil in the form of oral spray (Gent) 25 mg (2 doses) 1 time per day for 1 month, patients with type 2 diabetes received 50 mg (4 injections) every other day for 1 month. In addition, most of the subjects took metformin and followed diet therapy.

RESULTS

In patients of both groups, the administration of Sildenafil oral spray led to a decrease in body weight, waist circumference, a decrease in insulin and Hemoglobin A1C level without changing of hypoglycemic therapy in those with type 2 DM. In men with prediabetes, a decrease in fasting insulin levels was found. During treatment, half of the persons with impaired glucose metabolism had an increase in the testosterone level. According to IIEF-5, a decrease in the severity of ED in both groups of patients was seen. In men with prediabetes, the average IIEF-5 score increased from 15.98 to 21.57 points (p<0.05), while in patients with type 2 DM it improved from 12.18 to 18.44 points (p<0.05). Doppler ultrasound indicated a significant increase in the maximum systolic blood flow velocity and arterial resistivity index after treatment with Sildenafil oral spray in patients with both prediabetes and type 2 diabetes.

CONCLUSION

Sildenafil oral spray can be effectively used for the treatment of ED in men with type 2 DM and prediabetes.

Associations between prenatal alcohol and tobacco exposure on Doppler flow velocity waveforms in pregnancy: a South African study

BACKGROUND

The negative impact of prenatal alcohol and tobacco exposure (PAE and PTE) on fetal development and birth outcomes are well described, yet pathophysiologic mechanisms are less clear. Our aim was to investigate (1) the associations between quantity, frequency and timing (QFT) of PAE and PTE with blood flow velocities in arteries of the fetal-placental-maternal circulation and (2) the extent to which combined effect of QFT of PAE and/or PTE and Doppler flow velocity waveforms (FWV) predict infant birth weight.

METHODS

The Safe Passage Study is a cohort based in urban Cape Town, South Africa. Recruitment occurred between 2007 and 2015. Information on QFT of PAE and PTE was collected prospectively at up to 4 occasions during pregnancy using a modified Timeline Follow-Back approach. Ultrasound examinations consisted of Doppler flow velocity waveforms of the uterine, umbilical (UA) and fetal middle cerebral arteries for the pulsatility index (PI) at 20-24 and 34-38 weeks. Exclusion criteria included: twin pregnancies, stillbirths, participants exposed to other drugs. The sample was divided into three groups (controls, PAE and PTE) and included 1396 maternal-fetal-dyads assessed during the second trimester; 1398 assessed during the third trimester.

RESULTS

PTE was associated with higher UA PI values in second and third trimesters (p < 0.001), compared to the PAE and control group. The total amount of cigarettes smoked during pregnancy was positively correlated with UA PI values (r = 0.087, p < 0.001). There was a positive correlation between cigarettes smoked per day in trimester one (r = 0.091, p < 0.01), and trimester two (r = 0.075, p < 0.01) and UA PI (in trimester two), as well as cigarettes smoked per day in trimester two (r = 0.058, p < 0.05) and trimester three (r = 0.069, p < 0.05) and the UA PI in trimester three. Generalized additive models indicated that PAE in trimester two, PTE in trimester one and Doppler FWV in trimester three were significant predictors of birth weight in this sample.

CONCLUSION

In our study, PTE in trimesters two and three resulted in increased vascular resistance of the placenta. These findings highlight nuance in associations between PAE, PTE and blood flow velocities in arteries of the fetal-placental-maternal circulation and birth weight, suggesting that quantity and timing are important factors in these relationships.

Doppler Indices of the Uterine, Umbilical and Fetal Middle Cerebral Artery in Diabetic versus Non-Diabetic Pregnancy: Systematic Review and Meta-Analysis

Background and Objectives: The aim of this study was to assess the differences in Doppler indices of the uterine (Ut), umbilical (UA), and middle cerebral artery (MCA) in diabetic versus non-diabetic pregnancies by conducting a comprehensive systematic review of the literature with a meta-analysis. Materials and Methods: PubMed, Web of Science, and SCOPUS were searched for studies that measured the pulsatility index (PI), resistance index (RI), and systolic/diastolic ratio index (S/D ratio) of the umbilical artery, middle cerebral artery, and uterine artery in diabetic versus non-diabetic pregnancies. Two reviewers independently evaluated the eligibility of studies, abstracted data, and performed quality assessments according to standardized protocols. The standardized mean difference (SMD) was used as a measure of effect size. Heterogeneity was assessed using the I2 statistic. Publication bias was evaluated by means of funnel plots. Results: A total of 62 publications were included in the qualitative and 43 in quantitative analysis. The UA-RI, UtA-PI, and UtA-S/D ratios were increased in diabetic compared with non-diabetic pregnancies. Subgroup analysis showed that levels of UtA-PI were significantly higher during the third, but not during the first trimester of pregnancy in diabetic versus non-diabetic pregnancies. No differences were found for the UA-PI, UA-S/D ratio, MCA-PI, MCA-RI, MCA-S/D ratio, or UtA-RI between diabetic and non-diabetic pregnancies. Conclusions: This meta-analysis revealed the presence of hemodynamic changes in uterine and umbilical arteries, but not in the middle cerebral artery in pregnancies complicated by diabetes.

Use of a handheld Doppler to measure brachial and femoral artery occlusion pressure

Objective: Measurement of arterial occlusion pressure (AOP) is essential to the safe and effective use of blood flow restriction during exercise. Use of a Doppler ultrasound (US) is the "gold standard" method to measure AOP. Validation of a handheld Doppler (HHDOP) device to measure AOP could make the measurement of AOP more accessible to practitioners in the field. The purpose of this study was to determine the accuracy of AOP measurements of the brachial and femoral arteries using an HHDOP. Methods: We simultaneously measured AOP using a "gold standard" US and a HHDOP in the dominant and non-dominant arms (15 males; 15 females) and legs (15 males; 15 females). Results: There were no differences in limb circumference or limb volume in the dominant and non-dominant arms and legs between males and females or between the dominant and non-dominant arms and legs of males and females. The differences between US and HHDOP measures of AOP in the dominant and non-dominant arms and legs were either not significant or small (<10 mmHg) and of little practical importance. There were no sex differences in AOP measurements of the femoral artery (p > 0.60). Bland-Altman analysis yielded an average bias (-0.65 mmHg; -2.93 mmHg) and reasonable limits of agreement (±5.56 mmHg; ±5.58 mmHg) between US and HHDOP measures of brachial and femoral artery AOP, respectively. Conclusion: HHDOP yielded acceptable measures of AOP of the brachial and femoral arteries and can be used to measure AOP by practitioners for the safe and effective use of blood flow restriction. Due to the potential differences in AOP between dominant and non-dominant limbs, AOP should be measured in each limb.

Diabetic neuropathy results in vasomotor dysfunction of medium sized peripheral arteries

BACKGROUND

The effect of the sympathetic nervous system on peripheral arteries causes vasoconstriction when smooth muscle cells in the walls of blood vessels contract, which leads to narrowing of arteries and reduction of the blood flow.

AIM

To compare sympathetic vasomotor activation of the brachial arteries in healthy subjects and patients with painful diabetic neuropathy; and therefore, to assess whether there is significant vasomotor dysfunction of medium sized arteries in diabetic neuropathy.

METHODS

The study included 41 diabetic neuropathy patients and 41 healthy controls. Baseline diameter and flow rate of the brachial arteries were measured. Then, using a bipolar stimulus electrode, a 10 mA, 1 Hz electrical stimulus was administered to the median nerve at the wrist level for 5 s. The brachial artery diameter and blood flow rate were re-measured after stimulation.

RESULTS

In the control group, the median flow rate was 70.0 mL/min prior to stimulation and 35.0 mL/min after stimulation, with a statistically significant decrease (P < 0.001), which is consistent with sympathetic nervous system functioning (vasoconstriction). In the diabetic neuropathy group, median flow rate before the stimulation was 35.0 mL/min. After stimulation, the median flow rate was 77.0 mL/min; thus, no significant decrease in the flow rate was detected. In the control group, the median brachial artery diameter, which was 3.6 mm prior to stimulation, decreased to 3.4 mm after stimulation, and this decrease was also statistically significant (P = 0.046). In the diabetic neuropathy group, the median brachial artery diameter increased from 3.4 mm to 3.6 mm following nerve stimulation. Once again, no narrowing was observed.

CONCLUSION

Our research suggests that diabetic neuropathy results in significant vasomotor dysfunction of medium sized peripheral arteries. Physiological vasoconstriction in response to sympathetic activation is impaired in diabetic neuropathy.

Diabetic neuropathy results in vasomotor dysfunction of medium sized peripheral arteries

BACKGROUND

The effect of the sympathetic nervous system on peripheral arteries causes vasoconstriction when smooth muscle cells in the walls of blood vessels contract, which leads to narrowing of arteries and reduction of the blood flow.

AIM

To compare sympathetic vasomotor activation of the brachial arteries in healthy subjects and patients with painful diabetic neuropathy; and therefore, to assess whether there is significant vasomotor dysfunction of medium sized arteries in diabetic neuropathy.

METHODS

The study included 41 diabetic neuropathy patients and 41 healthy controls. Baseline diameter and flow rate of the brachial arteries were measured. Then, using a bipolar stimulus electrode, a 10 mA, 1 Hz electrical stimulus was administered to the median nerve at the wrist level for 5 s. The brachial artery diameter and blood flow rate were re-measured after stimulation.

RESULTS

In the control group, the median flow rate was 70.0 mL/min prior to stimulation and 35.0 mL/min after stimulation, with a statistically significant decrease (P < 0.001), which is consistent with sympathetic nervous system functioning (vasoconstriction). In the diabetic neuropathy group, median flow rate before the stimulation was 35.0 mL/min. After stimulation, the median flow rate was 77.0 mL/min; thus, no significant decrease in the flow rate was detected. In the control group, the median brachial artery diameter, which was 3.6 mm prior to stimulation, decreased to 3.4 mm after stimulation, and this decrease was also statistically significant (P = 0.046). In the diabetic neuropathy group, the median brachial artery diameter increased from 3.4 mm to 3.6 mm following nerve stimulation. Once again, no narrowing was observed.

CONCLUSION

Our research suggests that diabetic neuropathy results in significant vasomotor dysfunction of medium sized peripheral arteries. Physiological vasoconstriction in response to sympathetic activation is impaired in diabetic neuropathy.

Peripheral cord insertion is associated with adverse pregnancy outcome only when accompanied by clinically significant placental pathology

OBJECTIVE

To examine the relationship between umbilical cord insertion site, placental pathology and adverse pregnancy outcome in a cohort of normal and complicated pregnancies.

METHODS

Sonographic measurement of the cord insertion and detailed placental pathology were performed in 309 participants. Associations between cord insertion site, placental pathology and adverse pregnancy outcome (pre-eclampsia, preterm birth, small-for-gestational age) were examined.

RESULTS

A total of 93 (30%) participants were identified by pathological examination to have a peripheral cord insertion site. Only 41 of the 93 (44%) peripheral cords were detected by prenatal ultrasound. Peripherally inserted cords were associated significantly (P < 0.0001) with diagnostic placental pathology (most commonly with maternal vascular malperfusion (MVM)); of which 85% had an adverse pregnancy outcome. In cases of isolated peripheral cords, without placental pathology, the incidence of adverse outcome was not statistically different when compared to those with central cord insertion and no placental pathology (31% vs 18%; P = 0.3). A peripheral cord with an abnormal umbilical artery (UA) pulsatility index (PI) corresponded to an adverse outcome in 96% of cases compared to 29% when the UA-PI was normal.

CONCLUSIONS

This study demonstrates that peripheral cord insertion is often part of the spectrum of findings of MVM disease and is associated with adverse pregnancy outcome. However, adverse outcome was uncommon when there was an isolated peripheral cord insertion and no placental pathology. Therefore, additional sonographic and biochemical features of MVM should be sought when a peripheral cord is observed. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Accuracy of the Society of Radiologists in Ultrasound (SRU) Carotid Doppler Velocity Criteria for Grading North American Symptomatic Carotid Endarterectomy Trial (NASCET) Stenosis: A Meta-Analysis

PURPOSE

The Society of Radiologists in Ultrasound (SRU) consensus panel proposed six Doppler velocity cut points for classifying internal carotid artery (ICA) stenosis of 50% and 70% according to the North American Symptomatic Carotid Endarterectomy Trial (NASCET) method. Their relative accuracies have not been compared.

MATERIALS AND METHODS

Meta-analysis performed following comprehensive literature review and identification of manuscripts with graphs of individual patient NASCET ICA stenosis measured by arteriography versus ICA peak-systolic velocity (PSV), end-diastolic velocity (EDV) and ICA PSV to common carotid artery (CCA) PSV. True positives, true negatives, false positives, and false negatives were calculated and used in two-level mixed effects models. Hierarchical summary receiver operating characteristic (ROC) curves were generated. Areas under the ROC curves were estimated.

RESULTS

Nine studies performed between 1993 and 2016 were identified after review of 337 manuscripts. There were 1738 bifurcation data points extracted for PSV, 1026 for EDV, and 775 for ICA/CCA ratio. The highest sensitivity was 96% (95% CI: 93%, 98%) for PSV of 125 cm/s (50% stenosis) and highest specificity 86% (95% CI: 71%, 93%) for PSV of 230 cm/s (70% stenosis). Areas under the ROC curves ranged from a high of 0.93 (95% CI: 0.92, 0.95) for PSV (50% stenosis) to a low of 0.86 (95% CI: 0.84, 0.88) for EDV (70% stenosis).

CONCLUSIONS

The SRU consensus Doppler cut points vary in their accuracies for predicting ICA stenosis. The PSV cut points have tradeoffs: high sensitivity/low specificity for 50% stenosis and high specificity/moderate sensitivity for 70% stenosis.

Doppler Ultrasound Assessment of Tumor Vascularity in Locally Advanced Breast Cancer at Diagnosis and following Primary Systemic Chemotherapy

Aim

The primary goal of this research is to compare the morphological response, as determined by clinical and sonographic examination, to the gold standard, histology, in assessing the effectiveness of major systemic chemotherapy in patients with locally advanced breast cancer (LABC).

Materials and Methods

During the check and before each example of chemotherapy (FAC schedule), 54 patients with privately progressed, non-metastatic breast disease underwent a comprehensive clinical assessment, ultrasonography of the breast and axillae, and assortment and spooky Doppler appraisal to evaluate response to therapy.

Results

In 90% of instances, Doppler provided early insight into how a patient might respond to treatment. Disappearance of all vascular signals inside the tumor was shown to be the strongest predictor of full pathological response.

Conclusion

Patients with LABC may benefit from using color Doppler to determine how well chemotherapy is working.

Maternal Serum Angiogenic Profile and Its Correlations with Ultrasound Parameters and Perinatal Results in Normotensive and Preeclamptic Pregnancies Complicated by Fetal Growth Restriction

FGR is a complication of pregnancy in which the fetus does not reach its programmed growth potential due to placental reasons and it is the single largest risk factor of stillbirth. Babies with FGR are at increased risk of mortality and morbidity not only in the perinatal period, but also in later life. FGR presents a huge challenge for obstetricians in terms of its detection and further monitoring of pregnancy. The ultrasound is the gold standard here; apart from assessing fetal weight, it is used to measure Doppler flows in maternal and fetal circulation. It seems that additional tests, like biochemical angiogenic factors measurement would be helpful in diagnosing FGR, identifying fetuses at risk and adjusting the surveillance model. The study aimed to assess the potential relationship between the concentration of sEng, sFlt-1, PlGF, and the sFlt-1/PlGF ratio in maternal serum at delivery and maternal and fetal Doppler flow measurements as well as perinatal outcomes in pregnancies complicated by FGR with and without PE, isolated PE cases and normal pregnancies. The use of angiogenic markers is promising not only in PE but also in FGR. Numerous correlations between ultrasound and Doppler studies, perinatal outcomes and disordered angiogenesis marker levels in maternal serum suggest that biochemical parameters have a great potential to be used as a complementary method to diagnose and monitor pregnancies with FGR. The, PlGF in particular, could play an outstanding role in this regard.

Life's Essential 8 and carotid artery plaques: the Swedish cardiopulmonary bioimage study

Background

To quantify cardiovascular health (CVH), the American Heart Association (AHA) recently launched an updated construct of the "Life's Simple 7" (LS7) score, the "Life's Essential 8" (LE8) score. This study aims to analyse the association between both CVH scores and carotid artery plaques and to compare the predictive capacity of such scores for carotid plaques.

Methods

Randomly recruited participants aged 50-64 years from the Swedish CArdioPulmonary bioImage Study (SCAPIS) were analysed. According to the AHA definitions, two CVH scores were calculated: i) the LE8 score (0, worst CVH; 100, best CVH) and two different versions of the LS7 score [(0-7) and (0-14), 0 indicating the worst CVH]. Ultrasound-diagnosed carotid plaques were classified as no plaque, unilateral, and bilateral plaques. Associations were studied by adjusted multinomial logistic regression models and adjusted (marginal) prevalences, while comparison between LE8 and LS7 scores was performed through receiver operating characteristic (ROC) curves.

Results

After exclusions, 28,870 participants remained for analysis (50.3% women). The odds for bilateral carotid plaques were almost five times higher in the lowest LE8 (<50 points) group [OR: 4.93, (95% CI: 4.19-5.79); adjusted prevalence 40.5%, (95% CI: 37.9-43.2)] compared to the highest LE8 (≥80 points) group [adjusted prevalence 17.2%, (95% CI: 16.2-18.1)]. Also, the odds for unilateral carotid plaques were more than two times higher in the lowest LE8 group [OR: 2.14, (95% CI: 1.82-2.51); adjusted prevalence 31.5%, (95% CI: 28.9-34.2)] compared to the highest LE8 group [adjusted prevalence 29.4%, (95% CI: 28.3-30.5)]. The areas under ROC curves were similar between LE8 and LS7 (0-14) scores: for bilateral carotid plaques, 0.622 (95% CI: 0.614-0.630) vs. 0.621 (95% CI: 0.613-0.628), P = 0.578, respectively; and for any carotid plaque, 0.602 (95% CI: 0.596-0.609) vs. 0.600 (95% CI: 0.593-0.607), P = 0.194, respectively.

Conclusion

The new LE8 score showed inverse and dose-response associations with carotid plaques, particularly bilateral plaques. The LE8 did not outperform the conventional LS7 score, which showed similar ability to predict carotid plaques, especially when scored as 0-14 points. We conclude that both the LE8 and LS7 may be useful in clinical practice for monitoring CVH status in the adult population.

Low hepatic artery resistive index on Doppler ultrasound performed on the first post-liver transplant day is associated both with hepatic artery thrombosis and decreased graft survival

PURPOSE

Although liver transplantation (LT) outcomes have improved significantly over the last decades, early vascular complications are still associated with elevated risks of graft failure. Doppler ultrasound (DUS) enables detection of vascular complications, provides hepatic artery Resistive Index (RI). The aim of our study was to evaluate the association of the RI parameters of DUS performed in the first post-transplant week with post-transplant outcomes.

METHODS

All consecutive patients undergoing a first LT between 2001 and 2019 at a single center were included. Patients were divided into two groups: RI < 0.55 and RI ≥ 0.55. Patients were also divided according to the presence or absence of hepatic artery thrombosis (HAT). Graft survival was compared between groups.

RESULTS

Overall, 338 patients were included. HAT occurred in 23 patients (6.8%), of which 7 were partial and 16, complete. Biliary complications were more common in patients with HAT (10 [43.5%]) vs. 38 [12.1%] [p < 0.001]). Graft survival was lower for patients with HAT (p = 0.047). Also, RI < 0.55 was associated with increased incidence of HAT (p < 0.001). Additionally, patients with RI < 0.55 on post-operative day 1 had decreased graft survival as compared to patients with RI > 0.55 (p = 0.041). RI on post-operative day 3 and 5 was not predictive of inferior graft outcomes.

CONCLUSIONS

Intensive use of DUS in the early post-LT period offers the possibility of early diagnosis of vascular complications, guiding medical and surgical management of HAT. Additionally, according to our data, low RI (< 0.55) on the first postoperative day also is a predictor of HAT and decreased graft-survival.

Feasibility and Clinical Value of Intraprocedural Doppler Ultrasonography Blood Flow Parameters During Peripheral Endovascular Procedures for Limb Salvage: A Pilot Study

PURPOSE

To investigate whether Doppler ultrasound (DUS) blood flow parameters could serve as quantifiable functional endpoints of peripheral endovascular arterial procedures for chronic limb-threatening ischemia (CLTI), influencing wound healing.

METHODS

This is a prospective single-center study investigating intraprocedural DUS parameters (pulsatility index [PI] and pedal acceleration time [PAT]) in quantifying immediate hemodynamic alterations in consecutive CLTI patients with wound, ischemia, and foot infection wound class ≥1 undergoing endovascular interventions. Primary endpoints were feasibility of preendovascular and postendovascular treatment measurements of PI/PAT, quantification of immediate PI/PAT modifications of the posterior and anterior foot circulation following revascularization, the correlation between PI and PAT, and 6-month complete wound healing. Secondary endpoints included the 6-month limb salvage (no major amputation) and complete and partial wound healing rates.

RESULTS

A total of 28 patients (75.0% male) were enrolled, and 68 vessels were treated. The overall mean PAT values significantly decreased from 154.15±70.35 ms preprocedural to 107.21±49.6 ms postprocedural (p<0.01), and the mean PI values significantly increased from 0.93±0.99 to 1.92±1.96 (p<0.01). Postprocedural PAT at the anterior tibial (r²=0.804; p=0.346) and the posterior tibial arteries (r²=0.784; p=0.322) had a strong correlation and postprocedural PI at the anterior tibial (r²=0.704; p=0.301) and the posterior tibial arteries (r²=0.707; p=0.369) had a good correlation with 6-month complete wound healing. The 6-month complete and partial wound healing rates were 38.1% and 47.6%, respectively. Limb salvage was 96.4% and 92.4% at 6 and 12 months of follow-up, respectively.

CONCLUSIONS

Pedal acceleration time and PI accurately detected immediate hemodynamic changes of foot perfusion following revascularization and could serve as prognostic factors of wound healing in patients with CLTI.

CLINICAL IMPACT

Intraprocedural measurement of simple Doppler ultrasound blood flow parameters, Pulsatility Index (PI) and Pedal Acceleration Time (PAT), accurately detected immediate hemodynamic changes of foot perfusion following endovascular revascularization and could therefore serve as intraprocedural prognostic factors of wound healing in patients with chronic limb-threatening ischemia. This is the first time that PI has been proposed as a hemodynamic index of successful angioplasty outcome. The optimization of intraprocedural PAT and PI could be used to guide angioplasty and predict clinical success.

Effect of shoeing horses with eggbar shoes and shoes with wedge pads on blood flow parameters in the lateral digital artery in the Doppler ultrasound

A sound knowledge of horseshoe impact on blood flow parameters is required for making shoeing decisions and selecting the most appropriate types of shoes. The aim of this study was to determine the effect of horse shoeing with egg bar shoes and shoes with wedge pads on blood flow parameters in the lateral palmar digital artery measured by Doppler ultrasound. The study was conducted on 16 horses divided into two groups. Horses from group 1 were shod with egg bar shoes. Horses from group 2 were shod with shoes with wedge pads. Doppler ultrasound parameters of the lateral palmar digital artery at the level of the metacarpophalangeal joint were evaluated. Doppler tests were performed before and after shoeing within a monthly interval. The results of the study indicate that egg bar shoes have a greater impact on blood circulation in the distal part of the equine limb than shoes with wedge pads. However, the only parameters to have changed substantially after shoeing with egg bar shoes were end-diastolic velocity (EDV) and mean velocity (Vmn) in the lateral palmar digital artery. A low-resistance blood flow pattern was noted before shoeing. After shoeing in group 1, it remained unchanged in 5 horses, whereas a high-resistance pattern was observed in 3 animals. A low-resistance blood flow pattern was noted in all group 2 horses after shoeing. The difference between the analyzed shoeing techniques could be attributed to increased pressure in the heel bulb area in horses shod with egg bar shoes. Wedge pads shift the load away from the heel bulbs, which might reduce the pressure on the palmar digital vessels and exert a smaller influence on the parameters measured in the Doppler ultrasound test.

The role of different Doppler parameters in predicting adverse neonatal outcomes in fetuses with late-onset fetal growth restriction

Objective

The aim of this study is to clarify the role of different Doppler parameters such as umbilicocerebral ratio (UCR), cerebroplacentouterine ratio (CPUR), aortic isthmus, renal artery, and umbilical vein flow Doppler in predicting adverse neonatal outcomes in fetuses with late -onset fetal growth restriction.

Materials and Methods

The study included all patients diagnosed with fetal growth restriction at 32-39 weeks' gestation between 01/02/2020 and 01/02/2022 and treated at the Department of Obstetrics and Gynecology, Inonu University School of Medicine.

Results

Patients included in the study had a median gestational week at delivery of 37 (minimum 33+0-maximum 39+0), median CPR of 1.42 (minimum-maximum 0.43-3.57), and median UCR of 0.7 (minimum-maximum 0.28-2.3). Receiver operating characteristic analysis was performed to determine the performance of the measured obstetric Doppler parameters in predicting the development of adverse neonatal outcomes. Umbilical venous blood flow showed the best performance in predicting adverse neonatal outcomes [area under the curve 0.952, 95% confidence interval (CI) 0.902-0.981, p<0.001]. Multivariate logistic regression analysis showed that fetuses with abnormal CPUR had a 4.5-fold (95% CI 0.084-0.583, p=0.02) increased risk of adverse neonatal outcome, whereas fetuses with abnormal umbilical venous flow had a 1.07-fold (95% CI 0.903-0.968, p<0.001) increased risk of adverse neonatal outcome.

Conclusion

The results of this study demonstrate that the use of UCR, CPUR, umbilical venous flow, and aortic isthmus PI Doppler parameters along with umbilical artery PI and CPR are effective in predicting adverse neonatal outcomes in fetuses with late -onset fetal growth restriction.

Development and Evaluation of a Multifrequency Ultrafast Doppler Spectral Analysis (MFUDSA) Algorithm for Wall Shear Stress Measurement: A Simulation and In Vitro Study

Cardiovascular pathology is the leading cause of death and disability in the Western world, and current diagnostic testing usually evaluates the anatomy of the vessel to determine if the vessel contains blockages and plaques. However, there is a growing school of thought that other measures, such as wall shear stress, provide more useful information for earlier diagnosis and prediction of atherosclerotic related disease compared to pulsed-wave Doppler ultrasound, magnetic resonance angiography, or computed tomography angiography. A novel algorithm for quantifying wall shear stress (WSS) in atherosclerotic plaque using diagnostic ultrasound imaging, called Multifrequency ultrafast Doppler spectral analysis (MFUDSA), is presented. The development of this algorithm is presented, in addition to its optimisation using simulation studies and in-vitro experiments with flow phantoms approximating the early stages of cardiovascular disease. The presented algorithm is compared with commonly used WSS assessment methods, such as standard PW Doppler, Ultrafast Doppler, and Parabolic Doppler, as well as plane-wave Doppler. Compared to an equivalent processing architecture with one-dimensional Fourier analysis, the MFUDSA algorithm provided an increase in signal-to-noise ratio (SNR) by a factor of 4-8 and an increase in velocity resolution by a factor of 1.10-1.35. The results indicated that MFUDSA outperformed the others, with significant differences detected between the typical WSS values of moderate disease progression (p = 0.003) and severe disease progression (p = 0.001). The algorithm demonstrated an improved performance for the assessment of WSS and has potential to provide an earlier diagnosis of cardiovascular disease than current techniques allow.

Hepatic and portal vein Doppler ultrasounds in assessing liver inflammation and fibrosis in chronic HBV infection with a normal ALT level

Aims

To discuss the clinical value of hepatic and portal vein Doppler ultrasounds in assessing liver inflammation and fibrosis in patients with chronic hepatitis B virus (HBV) infection, and a normal alanine transaminase (ALT) level.

Methods

94 patients with chronic HBV infections who had undergone ultrasound-guided liver biopsies were enrolled and grouped by the liver tissue pathological results. Analyzed the differences and correlation between parameters of the hepatic and portal vein Doppler ultrasounds are discussed across different degrees of liver inflammation and fibrosis.

Results

There were 27 patients with no significant liver damage and 67 patients with significant liver damage, there were significant differences in the parameters of the hepatic and portal vein Doppler ultrasounds between them (p < 0.05). As liver inflammation was aggravated, the inner diameter of the portal vein increased, and the blood flow velocities of the portal and superior mesenteric veins decreased (p < 0.05). When liver fibrosis became more severe, the inner diameter of the portal vein increased, while the blood flow velocities of the portal, superior mesenteric, and splenic veins decreased, and the Doppler waveforms of hepatic veins became unidirectional or flat (p < 0.05). The receiver operating characteristic (ROC) curve showed the assessment efficacy of hepatic and portal vein Doppler ultrasounds was superior to abdominal Doppler ultrasound alone in assessing liver fibrosis, and the combination of the two examination techniques outperformed any technique used alone.

Conclusion

The hepatic and portal vein Doppler ultrasounds have important clinical value for assessing liver fibrosis in patients with chronic HBV infection, to aid improve the diagnosis of liver fibrosis.

Continuous fetal cerebral blood flow monitoring during labor: A feasibility study

BACKGROUND

Current methods for fetal surveillance during labor have significant limitations. Since continuous fetal cerebral blood flow velocity (CBFV) monitoring during labor may add valuable information about fetal well-being, we developed a new ultrasound system called VisiBeam. VisiBeam consists of a flat probe (diameter 11 mm) with a cylindric plane wave beam, a vacuum attachment (diameter 40 mm), a scanner, and a display.

AIMS

To assess the feasibility of VisiBeam for continuous fetal CBFV monitoring during labor, and to study changes in CBFV during uterine contractions.

STUDY DESIGN

Descriptive observational study.

SUBJECTS

Twenty-five healthy women in labor with a singleton fetus in cephalic presentation at term. A transducer was placed over a fontanelle and attached to the fetal head with vacuum suction.

OUTCOME MEASURES

Achievement of continuous good quality fetal CBFV measures, such as peak systolic velocity, time averaged maximum velocity and end diastolic velocity. Trend plots of velocity measures display changes in CBFV between and during uterine contractions.

RESULTS

Good quality recordings during and between contractions were achieved in 16/25 fetuses. In twelve fetuses, CBFV measures were stable during uterine contractions. Four fetuses showed patterns of reduced CBFV velocity measures during contractions.

CONCLUSIONS

Continuous fetal CBFV monitoring by VisiBeam was feasible in 64 % of the subjects during labor. The system displayed variations of fetal CBFV not available by today's monitoring techniques and motivates for further studies. However, improvement of the probe attachment is required to ensure good quality signal in a higher proportion of fetuses during labor.

Influence of hyperthermic intraperitoneal chemotherapy on renal blood perfusion

PURPOSE

Hyperthermic intraperitoneal chemotherapy (HIPEC) is accompanied with an increased risk of acute kidney injury (AKI). Whether AKI is induced by chemotoxicity or hyperthermia-related changes in renal perfusion remains controversial. The influence of HIPEC on renal perfusion has not been evaluated in patients yet.

METHODS

Renal blood perfusion was assessed in ten patients treated with HIPEC by intraoperative renal Doppler pulse-wave ultrasound. Ultrasound (US) examinations were performed pre-, intra-, and postoperative with analyses of time-velocity curves. Patient demographics, surgical details, and data regarding renal function were recorded perioperatively. For evaluation of renal Doppler US to predict AKI, patients were divided in two groups with (AKI +) and without (AKI -) kidney injury.

RESULTS

Throughout HIPEC perfusion, neither significant nor consistent changes in renal perfusion could be observed. Postoperative AKI occurred in 6 of 10 participating patients. Intraoperative renal resistive index (RRI) values > 0.8 were observed in one patient developing stage 3 AKI according KDIGO criteria. At 30 min in perfusion, RRI values were significantly higher in AKI + patients.

CONCLUSION

AKI is a common and frequent complication after HIPEC, but underlying pathophysiology remains elusive. High intraoperative RRI values may indicate an increased risk of postoperative AKI. Present data challenges the relevance of hyperthermia-derived hypothesis of renal hypoperfusion with prerenal injury during HIPEC. More attention should be drawn towards chemotoxic-induced hypothesis of HIPEC-induced AKI and caution applying regimens containing nephrotoxic agents in patients. Further confirmatory and complementary studies on renal perfusion as well as pharmacokinetic HIPEC studies are required.

FLUST: A fast, open source framework for ultrasound blood flow simulations

BACKGROUND AND OBJECTIVE

Ultrasound based blood velocity estimation is a continuously developing frontier, where the vast number of possible acquisition setups and velocity estimators makes it challenging to assess which combination is better suited for a given imaging application. FLUST, the Flow-Line based Ultrasound Simulation Tool, may be used to address this challenge, providing a common platform for evaluation of velocity estimation schemes on in silico data. However, the FLUST approach had some limitations in its original form, including reduced robustness for phase sensitive setups and the need for manual selection of integrity parameters. In addition, implementation of the technique and therefore also documentation of signal integrity was left to potential users of the approach.

METHODS

In this work, several improvements to the FLUST technique are proposed and investigated, and a robust, open source simulation framework developed. The software supports several transducer types and acquisition setups, in addition to a range of different flow phantoms. The main goal of this work is to offer a robust, computationally cheap and user-friendly framework to simulate ultrasound data from stationary blood velocity fields and thereby facilitate design and evaluation of estimation schemes, including acquisition design, velocity estimation and other post-processing steps.

RESULTS

The technical improvements proposed in this work resulted in reduced interpolation errors, reduced variability in signal power, and also automatic selection of spatial and temporal discretization parameters. Results are presented illustrating the challenges and the effectiveness of the solutions. The integrity of the improved simulation framework is validated in an extensive study, with results indicating that speckle statistics, spatial and temporal correlation and frequency content all correspond well with theoretical predictions. Finally, an illustrative example shows how FLUST may be used throughout the design and optimization process of a velocity estimator.

CONCLUSIONS

The FLUST framework is available as a part of the UltraSound ToolBox (USTB), and the results in this paper demonstrate that it can be used as an efficient and reliable tool for the development and validation of ultrasound-based velocity estimation schemes.

Ultrasound evaluation of normal rhesus macaque fetal biometry and uteroplacental hemodynamics

Nonhuman primates are important preclinical models for translational, reproductive, and developmental science. Clinical evaluation of human fetal development is performed using standard sonographic-derived fetal biometry, assessments of amniotic fluid, and uteroplacental hemodynamics. These noninvasive in utero measurements provide important information regarding fetal growth and pregnancy well-being. Abnormalities in fetal growth, amniotic fluid volume, or placental vascular function are associated with placental insufficiency and adverse perinatal outcomes including stillbirth. The fetal biometric parameters most commonly assessed are biparietal diameter, head circumference, abdominal circumference, and femur diaphysis length. Evaluation of amniotic fluid volume includes measuring the fluid in four quadrants of the uterus to generate an Amniotic Fluid Index. Measures of uteroplacental hemodynamics typically include doppler assessment of the umbilical artery and ductus venosus, but can also include interrogation of the uterine artery and umbilical vein. In this study, we compile prenatal ultrasound data of fetal biometry, amniotic fluid measurements, and uteroplacental hemodynamics obtained from pregnancy studies conducted at the Oregon National Primate Research Center. The data included are from control unperturbed pregnant animals who have not undergone in utero experimental manipulations. This is the first report of comprehensive sonographic measurements following standardized clinical obstetric protocols utilized in rhesus macaques. The outcome is a large, prenatal ultrasound resource to be used by laboratory animal researchers in future nonhuman primate pregnancy studies for antenatal assessment.

Ultrasound Evaluation of Extracranial Cerebral Circulation (The Common, External and Internal Carotid Artery) in Different Breeds of Dogs

Noninvasive Doppler ultrasonography (US) examination is a standard method for the clinical evaluation of the carotid arteries. Extracranial cerebral circulation includes the common carotid artery (CCA), the external carotid artery (ECA), and the extracranial part of the internal carotid artery (ICA). The present study was conducted with the objective of assessing physiological normative values and describing the appearance of spectral waveforms of extracranial arteries in 104 healthy dogs of eight breeds divided into four groups according to weight. We also focused on searching for correlations for carotid blood velocities with the resistive index (RI), body weight and diameter, and differences between observers and the influence of sex in the calculations of Doppler parameters. In the evaluated breeds, significant differences were found in the velocity of peak systolic velocity (PSV) and end diastolic velocity (EDV). There was a strong correlation between body weight and peak systolic velocity, the RI index and CCA diameter. The intra-observer agreement for the PSV and EDV parameters in each vessel was considered excellent reliability, and overall interobserver agreement showed very good reliability. This study could improve the descriptions of physiological values and waveforms recorded in carotid arteries. Defining the physiological values of velocity and the resistive index (RI) helps in the easier identification of pathology and diagnosis of disease. Our results may be used for further studies of vascular diseases in veterinary medicine that correlate with the pathology of neurological disorders of ischemic origin, further in thromboembolism, oncologic disease and degenerative, proliferative and inflammatory diseases of the arteries that lead to stenosis.

Detecting the Change in Total Circulatory Flow with a Wireless, Wearable Doppler Ultrasound Patch: A Pilot Study

Measuring fluid responsiveness is important in the management of critically ill patients, with a 10-15% change in cardiac output typically being used to indicate "fluid responsiveness." Ideally, these changes would be measured noninvasively and peripherally. The aim of this study was to determine how the common carotid artery (CCA) maximum velocity changes with total circulatory flow when confounding factors are mitigated and determine a value for CCA maximum velocity corresponding to a 10% change in total circulatory flow.

DESIGN

Prospective observational pilot study.

SETTING

Patients undergoing elective, on-pump coronary artery bypass grafting (CABG) surgery.

PATIENTS

Fourteen patients were referred for elective coronary artery bypass grafting surgery.

INTERVENTIONS

Cardiopulmonary bypass (CPB) pump flow changes during surgery, as chosen by the perfusionist.

MEASUREMENTS

A hands-free, wearable Doppler patch was used for CCA velocity measurements with the aim of preventing user errors in ultrasound measurements. Maximum CCA velocity was determined from the spectrogram acquired by the Doppler patch. CPB flow rates were recorded as displayed on the CPB console, and further measured from the peristaltic pulsation frequency visible on the recorded Doppler spectrograms.

MAIN RESULTS

Changes in CCA maximum velocity tracked well with changes in CPB flow. On average, a 13.6% change in CCA maximum velocity was found to correspond to a 10% change in CPB flow rate.

CONCLUSIONS

Changes in CCA velocity may be a useful surrogate for determining fluid responsiveness when user error can be mitigated.

A Novel Spectral Index for Tracking Preload Change from a Wireless, Wearable Doppler Ultrasound

A wireless, wearable Doppler ultrasound offers a new paradigm for linking physiology to resuscitation medicine. To this end, the image analysis of simultaneously-acquired venous and arterial Doppler spectrograms attained by wearable ultrasound represents a new source of hemodynamic data. Previous investigators have reported a direct relationship between the central venous pressure (CVP) and the ratio of the internal jugular-to-common carotid artery diameters. Because Doppler power is directly related to the number of red cell scatterers within a vessel, we hypothesized that (1) the ratio of internal jugular-to-carotid artery Doppler power (V/A_POWER) would be a surrogate for the ratio of the vascular areas of these two vessels and (2) the V/A_POWER would track the anticipated CVP change during simulated hemorrhage and resuscitation. To illustrate this proof-of-principle, we compared the change in V/A_POWER obtained via a wireless, wearable Doppler ultrasound to B-mode ultrasound images during a head-down tilt. Additionally, we elucidated the change in the V/A_POWER during simulated hemorrhage and transfusion via lower body negative pressure (LBNP) and release. With these Interesting Images, we show that the Doppler V/A_POWER ratio qualitatively tracks anticipated changes in CVP (e.g., cardiac preload) which is promising for both diagnosis and management of hemodynamic unrest.

Umbilical Vein Blood Flow in Uncomplicated Pregnancies: Systematic Review of Available Reference Charts and Comparison with a New Cohort

The objectives of the study were (1) to perform a systematic review of the available umbilical vein blood flow volume (UV-Q) reference ranges in uncomplicated pregnancies; and (2) to compare the findings of the systematic review with UV-Q values obtained from a local cohort. Available literature in the English language on this topic was identified following the PRISMA guidelines. Selected original articles were further grouped based on the UV sampling sites and the formulae used to compute UV-Q. The 50th percentiles, the means, or the best-fitting curves were derived from the formulae or the reported tables presented by authors. A prospective observational study of uncomplicated singleton pregnancies from 20⁺⁰ to 40⁺⁶ weeks of gestation was conducted to compare UV-Q with the results of this systematic review. Fifteen sets of data (fourteen sets belonging to manuscripts identified by the research strategy and one obtained from our cohort) were compared. Overall, there was a substantial heterogeneity among the reported UV-Q central values, although when using the same sampling methodology and formulae, the values overlap. Our data suggest that when adhering to the same methodology, the UV-Q assessment is accurate and reproducible, thus encouraging further investigation on the possible clinical applications of this measurement in clinical practice.

Prediction of adverse neonatal outcome at admission for early-onset preeclampsia with severe features

BACKGROUND

Preeclampsia remains the leading cause of maternal morbidity and mortality. Consequently, research has focused on validating tools to predict maternal outcomes regarding clinical and biochemical features from the maternal compartment. However, preeclampsia also leads to neonatal complications due to placental insufficiency and prematurity, being the early-onset type associated with the poorest outcome. Hence, it is imperative to study whether these existing tools can predict adverse neonatal outcome.

OBJECTIVE

To assess the predictive value for adverse neonatal outcome of Doppler ultrasound, angiogenic factors and multi-parametric risk-score models in women with early-onset severe preeclampsia.

STUDY DESIGN

This is a prospective cohort study of consecutive singleton pregnancies complicated by early-onset (developed before 34 week's gestation) severe preeclampsia.

RESULTS

63 women with early-onset severe preeclampsia, 18 (28.6%) presented an adverse neonatal outcome. Placental growth factor (PlGF) showed the best discrimination between neonatal outcomes among angiogenic factors. PREP-L score is a multi-parametric risk-score for the prediction of complications in early-onset preeclampsia which includes maternal characteristics and clinical and analytical data obtained at admission. Good predictive values for the prediction of neonatal complications were found with the combination of PREP-L score with advanced Doppler (AUC ROC 0.9 95% CI 0.82-0.98]) and with PlGF levels (AUC ROC 0.91 [95% CI 0.84-0.98]).

CONCLUSIONS

The combination of maternal risk scoring (PREP-L score) with angiogenic factors or fetal Doppler ultrasound at the time of diagnosis of early-onset preeclampsia with severe features performs well in predicting adverse neonatal outcome.

Elevation of the head of bed reduces splanchnic blood flow in patients with intra-abdominal hypertension

BACKGROUND

Elevation of the head of bed (HOB) increases intra-abdominal pressure (IAP), but the effect of body position on abdominal splanchnic perfusion is not clear. The current study aimed to evaluate the effect of body position on the superior mesenteric artery (SMA) and the celiac artery (CA) blood flow by Doppler ultrasound in mechanically ventilated patients with intra-abdominal hypertension (IAH).

METHODS

This prospective cohort study included 53 mechanically ventilated patients with IAH. IAP, hemodynamic variables, and Doppler parameters of the SMA and CA were measured in the supine position. The measurements were repeated after the HOB angle was raised to 15° for 5 min and similarly at HOB angles of 30° and 45°. Finally, the patient was returned to the supine and these variables were re-measured.

RESULTS

The median (interquartile range, IQR) superior mesenteric artery blood flow (SMABF) decreased from 269 (244-322) to 204 (183-234) mL/min and the median (IQR) celiac artery blood flow (CABF) from 424 (368-483) to 376 (332-472) mL/min (both p<0.0001) while median (IQR) IAP increased from 14(13-16) to 16(14-18) mmHg (p<0.0001) when the HOB angle was changed from 0° to 15°. However, SMABF and CABF were maintained at similar levels from 15° to 30°, despite median (IQR) IAP increased to 17(15-18) mmHg (p = 0.0002). Elevation from 30° to 45° further reduced median (IQR) SMABF from 200(169-244) to 164(139-212) mL/min and CABF from 389(310-438) to 291(241-383) mL/min (both p<0.0001), Meanwhile, median (IQR) IAP increased to 19(18-21) mmHg (p<0.0001).

CONCLUSIONS

In mechanically ventilated patients with IAH, progressive elevation of the HOB from a supine to semi-recumbent position was associated with a gradual reduction in splanchnic blood flow. However, the results indicate that splanchnic blood flow is not further reduced when the HOB is elevated from 15° to 30°.This study confirms the influence of head-up angle on blood flow of the splanchnic organs and may contribute to the selection of the optimal position in patients with abdominal hypertension.

Relationship of cerebral blood volume with arterial and venous flow velocities in extremely low-birth-weight infants

Unstable cerebral blood flow is theorised to contribute to the occurrence of intraventricular haemorrhage (IVH) in extremely low-birth-weight infants (ELBWIs), which can be caused by increased arterial flow, increased venous pressure, and impaired autoregulation of brain vasculature. As a preliminary step to investigate such instability, we aimed to check for correlations of cerebral blood volume (CBV), as measured using near-infrared spectroscopy, with the flow velocities of the anterior cerebral artery (ACA) and internal cerebral vein (ICV), as measured using Doppler ultrasonography. Data were retrospectively analysed from 30 ELBWIs uncomplicated by symptomatic patent ductus arteriosus, which can influence ACA velocity, and severe IVH (grade ≥ 3), which can influence ICV velocity and CBV. The correlation between tissue oxygen saturation (StO₂₎ and mean blood pressure was also analysed as an index of autoregulation. CBV was not associated with ACA velocity; however, it was significantly correlated with ICV velocity (Pearson R = 0.59 [95% confidence interval: 0.29-0.78], P = 0.00061). No correlation between StO₂ and mean blood pressure was observed, implying that autoregulation was not impaired.    Conclusion: Although our findings are based on the premise that cerebral autoregulation was unimpaired in the ELBWIs without complications, the same result cannot be directly applied to severe IVH cases. However, our results may aid future research on IVH prediction by investigating the changes in CBV when severe IVH occurs during ICV velocity fluctuation. What is Known: • The pathogenesis of IVH includes unstable cerebral blood flow affected by increased arterial flow, increased venous pressure, and impaired cerebral autoregulation. • The approaches that can predict IVH are under discussion. What is New: • ACA velocity is not associated with CBV, but ICV velocity is significantly correlated with CBV. • CBV measured using NIRS may be useful in future research on IVH prediction.

Emergency scrotal exploration in children: Following a change in mindset in the UK

A survey of 200 emergency scrotal explorations done over four paediatric surgical centres in the UK revealed that the incidence of finding testicular torsion (TT) was 24% and the preoperative utilisation of Doppler ultrasound (DUS) was 10% [1]. We changed our practice to include better preoperative utilisation of a clinical risk score (TWIST) and DUS. This led to a significant increase in the incidence of finding TT from 18% to 53%. Obtaining a DUS did not lead to an increase in our orchidectomy rate. Adopting this change is possible in an NHS setting and it has significant clinical and economic benefits.

The Role of Ultrasound in Venous Thoracic Outlet Syndrome: Lesson Based on a Case Report

Thoracic outlet syndrome is a rare neurovascular disease, usually caused by compression of subclavian vessels and/or brachial plexus by a cervical rib or hypertrophic scalene muscles. When the subclavian artery is compressed, it can cause perfusion deficiency with cyanosis and greater fatigue of the upper limb; if the subclavian vein is compressed, it can cause venous congestion with swelling and pain in the upper limb. When compression affects the brachial plexus, it can cause tingling or paresthesia of the upper limb. It can be mono or bilateral, congenital, or acquired. The diagnosis of vascular alterations is difficult due to the rarity, poor knowledge, and nonspecificity of symptoms. Ultrasound allows to localize and measure the vascular stenosis degree. Failure to diagnose can expose patients to serious health risks. We describe a rare case of venous compression caused by anterior scalene muscle hypertrophy.

Standardization and quality control of Doppler and fetal biometric ultrasound measurements in low-income setting

OBJECTIVE

The aim of this study was to determine the quality of fetal biometry and pulsed-wave Doppler ultrasound measurements in a prospective cohort study in Uganda.

METHODS

This was an ancillary study of the Ending Preventable Stillbirths by Improving Diagnosis of Babies at Risk (EPID) project, in which women enroled in early pregnancy underwent Doppler and fetal biometric assessment at 32-40 weeks of gestation. Sonographers undertook 6 weeks of training followed by onsite refresher training and audit exercises. A total of 125 images for each of the umbilical artery (UA), fetal middle cerebral artery (MCA), left and right uterine arteries (UtA), head circumference (HC), abdominal circumference (AC) and femur length (FL) were selected randomly from the EPID study database and evaluated independently by two experts in a blinded fashion using objective scoring criteria. Inter-rater agreement was assessed using modified Fleiss' kappa for nominal variables and systematic errors were explored using quantile-quantile (Q-Q) plots.

RESULTS

For Doppler measurements, 96.8% of the UA images, 84.8% of the MCA images and 93.6% of the right UtA images were classified as of acceptable quality by both reviewers. For fetal biometry, 96.0% of the HC images, 96.0% of the AC images and 88.0% of the FL images were considered acceptable by both reviewers. The kappa values for inter-rater reliability of quality assessment were 0.94 (95% CI, 0.87-0.99) for the UA, 0.71 (95% CI, 0.58-0.82) for the MCA, 0.87 (95% CI, 0.78-0.95) for the right UtA, 0.94 (95% CI, 0.87-0.98) for the HC, 0.93 (95% CI, 0.87-0.98) for the AC and 0.78 (95% CI, 0.66-0.88) for the FL measurements. The Q-Q plots indicated no influence of systematic bias in the measurements.

CONCLUSIONS

Training local healthcare providers to perform Doppler ultrasound, and implementing quality control systems and audits using objective scoring tools in clinical and research settings, is feasible in low- and middle-income countries. Although we did not assess the impact of in-service retraining offered to practitioners deviating from prescribed standards, such interventions should enhance the quality of ultrasound measurements and should be investigated in future studies. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Recent Advances in Ultrasound of Soft Tissue Lesions

The superficial soft tissue lesions are commonly discovered during routine clinical practice. However, their diagnosis can be challenging. Non-invasive imaging can differentiate the features of various superficial soft tissue lesions. Moreover, imaging-based evaluations can help guide treatment and surgical planning, evaluate tumor extension, and perform staging and follow-up. Novel imaging modalities and techniques have been developed to improve diagnostic performance and differentiate between benign and malignant lesions in vivo. The authors reviewed the literature to determine how ultrasound has been utilized to diagnose and treat superficial soft tissue lesions.

A comparison between the superb microvascular imaging technique and conventional Doppler ultrasound in evaluating chronic allograft damage in renal transplant recipients

PURPOSE

The present study comparatively evaluates the performance of conventional Doppler ultrasound and superb microvascular imaging (SMI) in delineating the cortical microvessels of the transplanted kidney and compares the chronic allograft damage index (CADI) based on the examination of biopsy specimens with Doppler ultrasound and SMI findings.

METHODS

Sixty-eight renal transplant recipients underwent kidney biopsy with the pre-diagnosis of rejection before undergoing renal Doppler ultrasound examination between January 2020 and October 2020. The distance between the kidney capsule and the vascular structure closest to the kidney capsule was measured at the level of the lower pole in the transplanted kidney using color Doppler ultrasound (CDUS), power Doppler ultrasound (PDUS), and the SMI technique. The kidney size, resistive index at the level of the arcuate artery in the lower pole of the kidney, and renal artery flow rates were also measured.

RESULTS

The mean distance between the kidney capsule and the vessel was 2.44 ± 2.0 mm on CDUS, 1.34 ± 1.2 mm on PDUS, 0.99 ± 1.8 mm using the color SMI (cSMI) technique, and 0.86 ± 1.8 mm using the monochrome SMI (mSMI) technique. The study found that the SMI technique was superior to CDUS and PDUS in delineating the cortical microvasculature of the kidney. Both Doppler ultrasound examinations and the SMI technique proved effective in predicting the CADI (P = 0.006 for CDUS, P = 0.002 for PDUS, P = 0.018 for cSMI, and P = 0.027 for mSMI). Among conventional Doppler ultrasound examinations and the SMI technique, PDUS had the highest sensitivity, and cSMI had the highest specificity in differentiating high and low CADI values. Both the cSMI and mSMI techniques had similar sensitivity values, whereas only cSMI exhibited high specificity. CDUS had the lowest specificity value (P = 0.003 for CDUS, P = 0.002 for PDUS, P = 0.005 for cSMI, and P = 0.004 for mSMI).

CONCLUSION

The present study is the first in the literature to demonstrate the utility of the distance between the kidney capsule and the vessels in predicting the CADI score and to compare the Doppler ultrasound examinations and SMI technique in doing so.

Fetal adrenal gland size and umbilical artery Doppler in growth-restricted fetuses

OBJECTIVES

In fetal growth restriction (FGR), Doppler ultrasound is the most important method for the detection and management. However, additional parameters are needed to improve the distinction between constitutionally small fetuses and fetuses affected by FGR.

METHODS

A total of 445 singleton pregnancies between 23 and 40 weeks of gestation were included in our retrospective study, of which 67 with FGR and 378 normal fetuses. A 2D-plane of the fetal adrenal gland was obtained and the adrenal gland ratio was measured. Spearman's correlation coefficient was calculated to assess the association of fetal Doppler and adrenal gland ratio with outcome parameters. Logistic regression analysis was performed to assess the statistical significance of "PI of the umbilical artery" and "adrenal gland ratio" as prognostic factors for intrauterine growth restriction (IUGR).

RESULTS

PI of the umbilical artery was shown to correlate with outcome parameters (WG_Delivery: r=-0.125, p=0.008; birth weight: r=-0.268, p<0.001; birth weight centile: r=-0.248, p<0.001; APGAR at 5 min: r=-0.117, p=0.014). Adrenal gland ratio showed no correlation with any of the outcome parameters. In logistic regression however, both PI of the umbilical artery and the adrenal ratio were shown to be significantly associated with fetal IUGR. When combining the two parameters, predictive value was superior to the predictive value of each individual parameter (AUC 0.738 [95% CI 0.670; 0.806]).

CONCLUSIONS

The adrenal gland ratio can be a useful addition to Doppler ultrasound when it comes to the detection of fetal FGR. Prospective studies are needed to establish references ranges and cut-off values for clinical decision-making.

Transplant renal artery stenosis: utilization of machine learning to identify ancillary sonographic and doppler parameters to predict stenosis in patients with graft dysfunction

PURPOSE

To determine if ancillary sonographic and Doppler parameters can be used to predict transplant renal artery stenosis in patients with renal graft dysfunction.

MATERIALS AND METHODS

IRB-approved, HIPAA-compliant retrospective study included 80 renal transplant patients who had renal US followed by renal angiogram between January 2018 and December 2019. A consensus read of two radiologists recorded these parameters: peak systolic velocity, persistence of elevated velocity, grayscale narrowing, parvus tardus, delayed systolic upstroke, angle of the systolic peak (SP angle), and aliasing. Univariate analysis using t-test or chi-square was performed to determine differences between patients with and without stenosis. P values under 0.05 were deemed statistically significant. We used machine learning algorithms to determine parameters that could better predict the presence of stenosis. The algorithms included logistic regression, random forest, imbalanced random forest, boosting, and CART. All 80 cases were split between training and testing using stratified sampling using a 75:25 split.

RESULTS

We found a statistically significant difference in grayscale narrowing (p = 0.0010), delayed systolic upstroke (p = 0.0002), SP angle (p = 0.0005), and aliasing (p = 0.0024) between the two groups. No significant difference was found for an elevated peak systolic velocity (p = 0.1684). The imbalanced random forest (IRF) model was selected for improved accuracy, sensitivity, and specificity. Specificity, sensitivity, AUC, and normalized Brier score for the IRF model using all parameters were 73%, 81%, 0.82, and 69 in the training set, and 78%, 58%, 0.78, and 80 in the testing set. VIMP assessment showed that the combination of variables that resulted in the most significant change of the training set performance was that of grayscale narrowing and SP angle.

CONCLUSION

Elevated peak systolic velocity did not discriminate between patients with and without TRAS. Adding ancillary parameters into the machine learning algorithm improved specificity and sensitivity similarly in the training and testing sets. The algorithm identified the combination of lumen narrowing coupled with the angle of the systolic peak as better predictor of TRAS. This model may improve the accuracy of ultrasound for transplant renal artery stenosis.

Renal blood flow during exercise: understanding its measurement with Doppler ultrasound

The sympathetic nervous system (SNS) has a critical role in continuously coordinating responses to stimuli internal and external to the human body by appropriately modulating the activity of the organs it innervates. The SNS is activated in response to various physiological stressors, including exercise, which can involve a significant increase in SNS activity. An increase in SNS activity directed towards the kidneys causes vasoconstriction of afferent arterioles within the kidneys. This sympathetically mediated renal vasoconstriction decreases renal blood flow (RBF), causing significant blood flow redistribution towards active skeletal muscles during exercise. In research studies, different modes, intensities, and durations of exercise have been used to investigate the sympathetically mediated RBF response to exercise, and several methodological approaches have been used to quantify RBF. Doppler ultrasound provides noninvasive, continuous, real-time measurements of RBF and has emerged as a valid and reliable technique to quantify RBF during exercise. This innovative methodology has been applied in studies in which the RBF response to exercise has been examined in healthy young and older adults and patient populations such as those with heart failure and peripheral arterial disease. This valuable tool has enabled researchers to produce clinically relevant findings that have furthered our understanding of the effect of SNS activation on RBF in populations of health and disease. Therefore, the focus of this narrative review is to highlight the use of Doppler ultrasound in research studies that has provided important findings furthering our knowledge of the impact of SNS activation on RBF regulation in humans.

Effect of Obesity and Bariatric Surgery on Saphenous Veins

PURPOSE

Obesity is a risk factor for chronic venous disease (CVD) of the lower limbs (LL), affecting venous anatomy and physiology. Weight loss after bariatric surgery (BS) can reduce intra-abdominal pressure, improve mobility, and ultimately improve venous hemodynamics and CVD-related symptoms. There are no studies in the literature that adequately assess the effect of the obesity and BS on the LL veins, especially the saphenous veins (SV). The aim of this study was to evaluate the effects of obesity and BS on the saphenous veins.

METHODS

This is a longitudinal prospective study carried out from 2019 to 2021 with 19 patients, totaling 38 LL, underwent clinical evaluation (CEAP Classification) and by Doppler ultrasonography, to analyze their SV diameter and reflux measurements, in the preoperative period and again 6 months to 2 years after BS being performed.

RESULTS

There was no statistical difference between the groups regarding the characteristics of reflux in the SV among the evaluated LL. There was no significant increase in the diameter of the great SV in the majority of its segments. The groups were similar in terms of the small SV diameters. Moreover, a significant reduction in the clinical class of CEAP was observed after BS.

CONCLUSION

Obesity and bariatric surgery had no influence on diameter or reflux in saphenous veins, but a reduction in the CEAP Clinical Classification was observed in the postoperative period.

Use of new microcirculation software allows the demonstration of dermis vascularization

AIMS

Current ultrasound (US) Doppler techniques cannot demonstrate the vascularization of the dermis. The purpose of this study was to investigate whether the new Superb Vascular Imaging (SMI) and Microvascular Flow (MV-Flow) techniques improve the detection of normal dermis vessels. SMI and MV-Flow were compared side-by-side to conventional power-Doppler (PD) imaging.

METHODS

By using US, 50 healthy volunteers were evaluated at level of five body areas: forehead, forearm, palm, buttock, and thigh. Two off-site operators evaluated the images to assess the difference between SMI and PD imaging and between MV-Flow and PD imaging in terms of dermis flow amount. A 0-3 scoring system was adopted.

RESULTS

SMI scored grade 0 in 0% of body areas, grade 1 in 58%, grade 2 in 33%, and grade 3 in 9%. In comparison with SMI, PD scored grade 0 in 38% of body areas, grade 1 in 56%, grade 2 in 6%, and grade 3 in 0%. MV-Flow scored grade 0 in 0% of body areas, grade 1 in 52%, grade 2 in 43%, and grade 3 in 6%. Comparted to MV-Flow, PD scored grade 0 in 53% of body areas, grade 1 in 34%, grade 2 in 13%, and grade 3 in 0%. The difference in terms of sensitivity was statistically significant for all the body areas investigated.

CONCLUSIONS

We found both SMI and MV-Flow to be superior to PD imaging and capable to demonstrate normal vascularization of the dermis.

Topography of the Heart: Mapping the Fetal Heart Through SlowflowHD

SlowflowHD is a Doppler Ultrasound modality that is typically geared toward visualization of small-size vessels and low velocity blood flow. In this commentary, we emphasize the importance of implementing the use of SlowflowHD as an adjunct to traditional Doppler modalities in the echocardiography screening in both the first and second trimester. This modality carries many characteristics that allow it to overcome the limitations of our current ultrasound modalities and facilitate mapping of the entirety of the fetal heart. The clinical implications are significant in regard to earlier acquisition of diagnostic information to guide decision-making and patient counseling.

Grayscale median (GSM) post-processing, posterizing, and color mapping for carotid ultrasound

Factors related to atherosclerotic plaques may indicate instability, such as ulcerations, intraplaque hemorrhages, lipid core, thin or irregular fibrous cap, and inflammation. The grayscale median (GSM) value is one of the most widespread methods of studying atherosclerotic plaques and it is therefore important to comprehensively standardize image post-processing. Post-processing was performed using Photoshop 23.1.1.202. Images were standardized by adjusting the grayscale histogram curves, setting the darkest point of the vascular lumen (blood) to zero and the distal adventitia to 190. Posterization and color mapping were performed. A methodology that presents the current state of the art in an accessible and illustrative way should contribute to the dissemination of GSM analysis. This article describes and illustrates the process step by step.

The time cost of physiologically ineffective intravenous fluids in the emergency department: an observational pilot study employing wearable Doppler ultrasound

BACKGROUND

Little data exist on the time spent by emergency department (ED) personnel providing intravenous (IV) fluid to 'responsive' versus 'unresponsive' patients.

METHODS

A prospective, convenience sample of adult ED patients was studied; patients were enrolled if preload expansion was indicated for any reason. Using a novel, wireless, wearable ultrasound, carotid artery Doppler was obtained before and throughout a preload challenge (PC) prior to each bag of ordered IV fluid. The treating clinician was blinded to the results of the ultrasound. IV fluid was deemed 'effective' or 'ineffective' based on the greatest change in carotid artery corrected flow time (ccFT_∆) during the PC. The duration, in minutes, of each bag of IV fluid administered was recorded.

RESULTS

53 patients were recruited and 2 excluded for Doppler artifact. There were 86 total PCs included in the investigation comprising 81.7 L of administered IV fluid. 19,667 carotid Doppler cardiac cycles were analyzed. Using ccFT_∆ ≥  + 7 ms to discriminate 'physiologically effective' from 'ineffective' IV fluid, we observed that 54 PCs (63%) were 'effective', comprising 51.7 L of IV fluid, whereas, 32 (37%) were 'ineffective' comprising 30 L of IV fluid. 29.75 total hours across all 51 patients were spent in the ED providing IV fluids categorized as 'ineffective.'

CONCLUSIONS

We report the largest-known carotid artery Doppler analysis (i.e., roughly 20,000 cardiac cycles) in ED patients requiring IV fluid expansion. A clinically significant amount of time was spent providing physiologically ineffective IV fluid. This may represent an avenue to improve ED care efficiency.

Association of Prenatal Placental Function with Anthropometry and Body Composition through 2 years of Age in South African Infants: The UmbiBaby Study

BACKGROUND

Placental insufficiency negatively impacts fetal growth and body composition (BC), potentially affecting lifelong health. Placental insufficiency, detectable as an abnormal umbilical artery resistance index (UmA-RI) on Doppler ultrasonography, is highly prevalent in otherwise healthy South African pregnant women. Appropriate intervention reduces stillbirth and perinatal death, but research on long-term outcomes of surviving infants is lacking.

OBJECTIVES

To describe and compare anthropometry and BC during the first 2 y of life in a cohort of term-born infants with normal and abnormal prenatal UmA-RI.

METHODS

Term-born infants (n = 81; n = 55 normal, n = 26 abnormal UmA-RI on third trimester Doppler screening) were followed up at 8-time points until age 2 y. Anthropometric measurements were taken, and FFM and FM were assessed by deuterium dilution. Age- and sex-specific z-scores were calculated for anthropometric indices, FM, FFM, FM index (FMI), and FFM index (FFMI) using appropriate reference data. Anthropometry and BC of infants with normal and abnormal UmA-RI were compared using an independent t-test or Mann-Whitney test.

RESULTS

At most ages, group mean z-scores were <0 for length-for-age and FM and >0 for weight-for-length and FFM. Compared with infants with normal UmA-RI, infants with abnormal UmA-RI had significantly lower weight-for-age z-scores at birth (-0.77 ± 0.75 compared with -0.30 ± 1.10, P = 0.026), ages 10 wk to 9 mo (-0.4 ± 0.87 to -0.2 ± 1.12 compared with 0.3 ± 0.85 to 0.6 ± 1.09; P = 0.007-0.017) and 18 mo (-0.6 ± 0.82 compared with 0.1 ± 1.18; P = 0.037); length-for-age z-scores at ages ≤14 wk (-1.3 ± 1.25 to -0.9 ± 0.87 compared with -0.2 ± 1.04 to -0.1 ± 1.00; P = 0.004-0.021); and FFM-for-age z-scores at ages ≤9 mo (-0.1 ± 0.82 to 0.7 ± 0.71 compared with 0.7 ± 1.00 to 1.3 ± 0.85; P = 0.002-0.028). FFMI, percentage FFM, FM, percentage FM, and FMI showed no consistent significant differences.

CONCLUSIONS

Infants with abnormal UmA-RI had lower weight-for-age and length-for-age z-scores, particularly at younger ages, with proportionally lower FFM but no consistent differences in percentage FFM and FFMI. These findings merit further investigation in larger cohorts. J Nutr 2023;xx:xx-xx.

Developmental Ultrasound Characteristics in Guinea Pigs: Similarities with Human Pregnancy

BACKGROUND

Biometrical and blood flow examinations are fundamental for assessing fetoplacental development during pregnancy. Guinea pigs have been proposed as a good model to study fetal development and related gestational complications; however, longitudinal growth and blood flow changes in utero have not been properly described. This study aimed to describe fetal and placental growth and blood flow of the main intrauterine vascular beds across normal guinea pig pregnancy and to discuss the relevance of this data for human pregnancy.

METHODS

Pregnant guinea pigs were studied from day 25 of pregnancy until term (day ~70) by ultrasound and Doppler assessment. The results were compared to human data from the literature.

RESULTS

Measurements of biparietal diameter (BPD), cranial circumference (CC), abdominal circumference, and placental biometry, as well as pulsatility index determination of umbilical artery, middle cerebral artery (MCA), and cerebroplacental ratio (CPR), were feasible to determine across pregnancy, and they could be adjusted to linear or nonlinear functions. In addition, several of these parameters showed a high correlation coefficient and could be used to assess gestational age in guinea pigs. We further compared these data to ultrasound variables from human pregnancy with high similarities.

CONCLUSIONS

BPD and CC are the most reliable measurements to assess fetal growth in guinea pigs. Furthermore, this is the first report in which the MCA pulsatility index and CPR are described across guinea pig gestation. The guinea pig is a valuable model to assess fetal growth and blood flow distribution, variables that are comparable with human pregnancy.

Usefulness of Systemic Venous Ultrasound Protocols in the Prognosis of Heart Failure Patients: Results from a Prospective Multicentric Study

Mortality and re-admission rates for decompensated acute heart failure (AHF) is increasing overall and risk stratification might be challenging. We sought to evaluate the prognostic role of systemic venous ultrasonography in patients hospitalized for AHF. We prospectively recruited 74 AHF patients with a NT-proBNP level above 500 pg/mL. Then, multi-organ ultrasound assessments (lung, inferior vena cava (IVC), pulsed-wave Doppler (PW-Doppler) of hepatic, portal, intra-renal and femoral veins) were performed at admission, discharge, and follow-up (for 90 days). We also calculated the Venous Excess Ultrasound System (VExUS), a new score of systemic congestion based on IVC dilatation and pulsed-wave Doppler morphology of hepatic, portal and intra-renal veins. An intra-renal monophasic pattern (area under the curve (AUC) 0.923, sensitivity (Sn) 90%, specificity (Sp) 81%, positive predictive value (PPV) 43%, and negative predictive value (NPV) 98%), a portal pulsatility > 50% (AUC 0.749, Sn 80%, Sp 69%, PPV 30%, NPV 96%) and a VExUS score of 3 corresponding to severe congestion (AUC 0.885, Sn 80%, Sp 75%, PPV 33%, and NPV 96%) predicted death during hospitalization. An IVC above 2 cm (AUC 0.758, Sn 93.l% and Sp 58.3) and the presence of an intra-renal monophasic pattern (AUC 0. 834, sensitivity 0.917, specificity 67.4%) in the follow-up visit predicted AHF-related re-admission. Additional scans during hospitalization or the calculation of a VExUS score probably adds unnecessary complexity to the assessment of AHF patients. In conclusion, VExUS score does not contribute to the guidance of therapy or the prediction of complications, compared with the presence of an IVC greater than 2 cm, a venous monophasic intra-renal pattern or a pulsatility > 50% of the portal vein in AHF patients. Early and multidisciplinary follow-up visits remain necessary for the improvement of the prognosis of this highly prevalent disease.