Dynamic Ultrasound Localization Microscopy Without ECG-Gating.

OBJECTIVE: Dynamic Ultrasound Localization Microscopy (DULM) has first been developed for non-invasive Pulsatility measurements in the rodent brain. DULM relies on the localization and tracking of microbubbles (MBs) injected into the bloodstream, to obtain highly resolved velocity and density cine-loops. Previous DULM techniques required ECG-gating, limiting its application to specific datasets, and increasing acquisition time. The objective of this study is to eliminate the need for ECG-gating in DULM experiments by introducing a motion-matching method for time registration. METHODS: We developed a motion-matching algorithm based on tissue Doppler that leverages the cyclic tissue motion within the brain. Tissue Doppler was estimated for each group of frames in the acquisitions, at multiple locations identified as local maxima in the skin above the skull. Subsequently, each group of frames was time-registered to a reference group by delaying it based on the maximum correlation value between their respective tissue Doppler signals. This synchronization ensured that each group of frames aligned with the brain tissue motion of the reference group, and consequently, with its cardiac cycle. As a result, velocities of MBs could be averaged to retrieve flow velocity variations over time. RESULTS: Initially validated in ECG-gated acquisitions in a rat model (n = 1), the proposed method was successfully applied in a mice model in 2D (n = 3) and in a feline model in 3D (n = 1). Performing time-registration with the proposed motion-matching method or by using ECG-gating leads to similar results. For the first time, dynamic velocity and density cine-loops were extracted without the need for any information on the animal ECG, and complex dynamic markers such as the Pulsatility index were estimated. CONCLUSION: Results suggest that DULM can be performed without external gating, enabling the use of DULM on any ULM dataset where enough MBs are detectable. Time registration by motion-matching represents a significant advancement in DULM techniques, making DULM more accessible by simplifying its experimental complexity.

Dissecting the vascular-cognitive nexus: energetic vs. conventional hemodynamic parameters.

Blood pressure or flow measurements have been associated with vascular health and cognitive function. We proposed that energetic hemodynamic parameters may provide a more nuanced understanding and stronger correlation with cognitive function, in comparisons with conventional aortic and carotid pressure and flow parameters. The study comprised 1858 participants, in whom we assessed cognitive function via MoCA method, and measured central aortic and carotid pressure and flow waveforms. In addition to various pressure and flow parameters, we calculated energetic hemodynamic parameters through integration of pressure multiplying flow with respect to time. Energetic hemodynamic parameters, particularly aortic and carotid mean and pulsatile energy and pulsatility index (PI), were significantly associated with MoCA score more than any aortic and carotid pressure and flow parameters, after adjusting for age, sex, education, depression score, heart rate, BMI, HDL-cholesterol, and glucose levels. MoCA exhibited a strong positive relationship with carotid mean energy (standardized beta = 0.053, P = 0.0253) and a negative relationship with carotid energy PI (standardized beta = -0.093, P = 0.0002), exceeding the association with all traditional pressure- or flow-based parameters. Aortic pressure reflection coefficient at the aorto-carotid junction was positively correlated with mean carotid energy and negatively correlated with PI. Aortic characteristic impedance positively correlated with carotid energy PI but not mean energy. Our research indicates that energetic hemodynamic parameters, particularly carotid mean energy and carotid energy PI, have a stronger association with MoCA scores than traditional pressure- or flow-based metrics. This correlation with cognitive function is notably influenced by the properties of the aorto-carotid interface.

Assessment of childhood intracranial pressure: a comparative study of transcranial Doppler ultrasound indices and findings at ventriculoperitoneal shunt.

PURPOSE: This study compares transcranial Doppler (TCD) Pulsatility Index (PI) and Resistivity Index (RI) with intra-operative CSF opening pressure measured by manometric technique during ventriculoperitoneal (V-P) shunt in children with hydrocephalus. METHODS: It was a prospective, hospital-based study performed among patients diagnosed with hydrocephalus. Patients had TCD ultrasonography before V-P shunt. The TCD sonography was repeated within 1 week post-op, and at 1 month post-op. The PI and RI were retrieved after insonating the middle cerebral artery. Ventricular CSF opening pressure was measured. Associations between TCD indices and CSF pressure were determined using the t-test and the Wilcoxon rank /Mann-Whitney tests where the normality test failed. A p-value of < 0.05 was considered significant for associations. RESULTS: Fifty-two patients were enrolled with a mean age of 9.9 ± 11.5 months. Of these, 41 (78.8%) were aged ≤ 12 months. The mean CSF opening pressure was 21.4 ± 9.0. When raised, ICP was defined as opening pressure > 15 cm of H2O, high PI (≥ 1.19), and high RI (> 0.8) diagnosed it with a sensitivity of 55% and 50%, respectively. The mean pre-operative PI (1.17 ± 0.56) reduced to 0.96 (Z = - 2.032, p = 0.042), while that of RI (0.66 ± 0.17) also decreased to 0.58 (t = 2.906, p = 0.044) after V-P shunt surgery. A strong positive correlation exists between a reduction in PI and RI after V-P shunt (r = 0.743, p = 0.014). CONCLUSION: Both PI and RI significantly decrease following V-P shunt, but a single reading has a poor sensitivity in predicting ICP.

Rapid changes in cerebrovascular compliance during vasovagal syncope.

PURPOSE: The compensatory mechanisms supporting cerebral perfusion throughout head-up tilt (HUT) in patients with vasovagal syncope (VVS) remain unclear. We tested the hypothesis that increased cerebrovascular compliance (Ci) and decreased cerebrovascular resistance (CVR) support cerebral blood velocity (CBV) during pre-syncope in VVS. METHODS: Finger arterial blood pressure (ABP) and right middle cerebral artery blood velocity (CBV) were recorded in 15 individuals diagnosed with VVS (n = 11 female, mean age: 40 ± 16 years, mean body mass index: 24.9 ± 4.0 kg/m2) at supine rest and during HUT (80 degree angle). Individual ABP and CBV waveforms during VVS were input into a modified Windkessel model to calculate Ci and ohmic CVR. Gosling's pulsatility index (Pi; pulse amplitude/mean CBV) was calculated. RESULTS: Diastolic ABP, systolic ABP, mean ABP (72 ± 11 to 51 ± 12 mmHg), and CVR decreased progressively during presyncope (all P ≤ 0.04). As expected, systolic CBV was sustained (all P ≥ 0.29) while diastolic and mean CBV (51 ± 13 to 38 ± 13 mmHg) fell during presyncope (all P ≤ 0.04). Both Ci and Pi increased during presyncope (128 ± 97 and 60 ± 41%, respectively; all P ≤ 0.049) and were positively correlated (R2 = 0.79, P < 0.01). Increased Ci contributed to changes in mean CBV (P < 0.01) but decreased CVR did not (P = 0.28). CONCLUSIONS: These data provide evidence that Ci increases during presyncope in patients with VVS and is likely involved in the maintenance of systolic CBV during a fall in diastolic CBV. However, this regulation is not sufficient to preserve CBV in the presence of such extreme and progressive reductions in ABP.

Association of pulsatility index with total burden of cerebral small vessel disease and cognitive impairment.

OBJECTIVE: This study investigated the correlation between the pulsatility index (PI) of the middle cerebral artery with the total burden of cerebral small vessel disease and cognitive impairment. METHOD: Information on patients hospitalized in the Department of Neurology was collected retrospectively. These patients had complete clinical and laboratory data. The middle cerebral artery PI was measured using transcranial Doppler, a Mini-Mental State Examination (MMSE) was used to assess cognitive function, and the total cerebral small vessel disease burden was assessed using magnetic resonance imaging. Patients were grouped according to their scores for total imaging burden of cerebral small vessel disease and cognitive function. Logistic regression analysis assessed the association between the PI, total imaging burden, and cognitive impairment. Spearman analysis was used to evaluate the correlation between the PI and total imaging burden and cognitive impairment, and receiver operating characteristic (ROC) curves were used to determine the predictive value of the PI for cognitive function. RESULTS: The PI was higher in the cognitive impairment (CI) group than in the no-CI group. Binary logistic regression analysis showed that increased PI was an independent risk factor for CI (OR = 1.582; 95% CI: 1.043-2.401; p = .031) and total imaging burden (OR = 1.842; 95% CI: 1.274-2.663; p = .001). Spearman analysis found that the PI correlated negatively with the MMSE score (r = -.627, p < .001). ROC curve analysis showed the PI predicted CI with an area under the curve of 0.784. The PI combined with the total imaging burden predicted CI in cerebral small vessel disease with an area under the curve of 0.832. CONCLUSION: An increased PI was associated with CI and a high imaging burden in cerebral small vessel disease patients. The PI combined with the total burden score shows a high predictive value for CI.

Assessment of Pulmonary Arterial Vascular Impedance in Fetuses With Tetralogy of Fallot.

OBJECTIVE: To evaluate the vascular impedance of the pulmonary arteries in fetuses with tetralogy of Fallot (TOF) by Doppler echocardiography. METHODS: A total of 42 fetuses with TOF (TOF group) and 84 gestational age-matched normal fetuses (control group) were prospectively collected from the Second Xiangya Hospital of Central South University from August 2022 to January 2023. The severity of TOF was classified into mild TOF (z score ≥-2), moderate TOF (-4 < z score < -2), or severe TOF (z score ≤-4) according to the z score value of the pulmonary annulus diameter. The pulsatility index (PI) of the main pulmonary artery (MPA), distal left pulmonary artery (DLPA), and distal right pulmonary artery (DRPA) were measured by pulsed-wave Doppler. The differences in clinical data and echocardiographic parameters between TOF group, control group, and TOF subgroups were compared. RESULTS: Compared with the control group, MPA-PI increased significantly, whereas DLPA-PI and DRPA-PI decreased in TOF group (all P < .001). There were no significant differences in MPA-PI and DRPA-PI among mild TOF, moderate TOF, and severe TOF (all P > .05). However, DLPA-PI decreased significantly in severe TOF compared with mild TOF (P < .05). CONCLUSION: Fetuses with TOF presented increased vascular impedance in the pulmonary trunk and decreased impedance in distal pulmonary artery branches. Further large and follow-up studies are needed to demonstrate the associations between those changed vascular impedances and the development of PA in patients with TOF.

Pulmonary artery elastance as a predictor of hospital mortality in heart failure cardiogenic shock.

AIMS: The initial bundle of cares strongly affects haemodynamics and outcomes in acute decompensated heart failure cardiogenic shock (ADHF-CS). We sought to characterize whether 24 h haemodynamic profiling provides superior prognostic information as compared with admission assessment and which haemodynamic parameters best predict in-hospital death. METHODS AND RESULTS: All patients with ADHF-CS and with available admission and 24 h invasive haemodynamic assessment from two academic institutions were considered for this study. The primary endpoint was in-hospital death. Regression analyses were run to identify relevant predictors of study outcome. We included 127 ADHF-CS patients [65 (inter-quartile range 52-72) years, 25.2% female]. Overall, in-hospital mortality occurred in 26.8%. Non-survivors were older, with greater CS severity. Among admission variables, age [odds ratio (OR) = 1.06; 95% confidence interval (CI): 1.02-1.11; Padj = 0.005] and CPIRAP (OR = 0.62 for 0.1 increment; 95% CI: 0.39-0.95; Padj = 0.034) were found significantly associated with in-hospital death. Among 24 h haemodynamic univariate predictors of in-hospital death, pulmonary elastance (PaE) was the strongest (area under the curve of 0.77; 95% CI: 0.68-0.86). PaE (OR = 5.98; 95% CI: 2.29-17.48; Padj < 0.001), pulmonary artery pulsatility index (PAPi, OR = 0.77; 95% CI: 0.62-0.92; Padj = 0.013) and age (OR = 1.06; 95% CI: 1.02-1.11; Padj = 0.010) were independently associated with in-hospital death. Best cut-off for PaE was 0.85 mmHg/mL and for PAPi was 2.95; cohort phenotyping based on these PaE and PAPi thresholds further increased in-hospital death risk stratification; patients with 24 h high PaE and low PAPi exhibited the highest in-hospital mortality (56.2%). CONCLUSIONS: Pulmonary artery elastance has been found to be the most powerful 24 h haemodynamic predictor of in-hospital death in patients with ADHF-CS. Age, 24 h PaE, and PAPi are independently associated with hospital mortality. PaE captures right ventriclar (RV) afterload mismatch and PAPi provides a metric of RV adaptation, thus their combination generates four distinct haemodynamic phenotypes, enhancing in-hospital death risk stratification.

Verification of a simplified aneurysm dimensionless flow parameter to predict intracranial aneurysm rupture status.

OBJECTIVES: Aneurysm number (An) is a novel prediction tool utilizing parameters of pulsatility index (PI) and aneurysm geometry. An has been shown to have the potential to differentiate intracranial aneurysm (IA) rupture status. The objective of this study is to investigate the feasibility and accuracy of An for IA rupture status prediction using Australian based clinical data. METHODS: A retrospective study was conducted across three tertiary referral hospitals between November 2017 and November 2020 and all saccular IAs with known rupture status were included. Two sets of An values were calculated based on two sets of PI values previously reported in the literature. RESULTS: Five hundred and four IA cases were included in this study. The results demonstrated no significant difference between ruptured and unruptured status when using An ≥1 as the discriminator. Further analysis showed no strong correlation between An and IA subtypes. The area under the curve (AUC) indicated poor performance in predicting rupture status (AUC1 = 0.55 and AUC2 = 0.56). CONCLUSIONS: This study does not support An ≥1 as a reliable parameter to predict the rupture status of IAs based on a retrospective cohort. Although the concept of An is supported by hemodynamic aneurysm theory, further research is needed before it can be applied in the clinical setting. ADVANCES IN KNOWLEDGE: This study demonstrates that the novel prediction tool, An, proposed in 2020 is not reliable and that further research of this hemodynamic model is needed before it can be incorporated into the prediction of IA rupture status.

Urinary sFlt-1 and PlGF as preeclampsia predictors: sFlt-1/creatinine ratio improves the prediction value.

OBJECTIVES: To evaluate the correlation between maternal serum and urinary soluble Fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) levels and to assess their potential value in preeclampsia and fetal growth restriction. STUDY DESIGN: This case-control longitudinal prospective study was performed in 49 singleton pregnant women, divided into two clinical groups, low risk pregnancy (n = 23) and pregnancy complicated by preeclampsia (n = 26). Maternal serum and urinary sFlt-1 and PlGF levels were quantified by electrochemiluminescence. Every patient underwent an ultrasound for fetal biometry. Doppler assessment was done when estimated fetal weight was under the 10th centile. ROC curves were used to evaluate the predictive capability of serum and urinary angiogenic biomarkers and their ratios on preeclampsia. Linear regression was used to compare the values of serum and urinary sFlt-1 and PlGF and their ratios. RESULTS: Urine biomarkers were positively associated with their serum values, being the best associated urinary PlGF (R2 = 0.73), which also showed the highest predictive capability of preeclampsia of urine biomarkers (AUC 0.866). The predictive capability of urinary sFlt-1 was much lower (AUC 0.640), but increased when adjusting by serum creatinine, a more precise parameter (AUC 0.863). CONCLUSIONS: Urinary PlGF could be a lesser invasive alternative to circulating biomarkers to monitor pregnancies complicated with preeclampsia that need repeated controls of their pregnancy complication. Urinary sFlt-1 values need adjustment by serum creatinine to be reliable.

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

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

Validation of the first-trimester machine learning model for predicting pre-eclampsia in an Asian population.

OBJECTIVES: To evaluate the performance of an artificial intelligence (AI) and machine learning (ML) model for first-trimester screening for pre-eclampsia in a large Asian population. METHODS: This was a secondary analysis of a multicenter prospective cohort study in 10 935 participants with singleton pregnancies attending for routine pregnancy care at 11-13+6 weeks of gestation in seven regions in Asia between December 2016 and June 2018. We applied the AI+ML model for the first-trimester prediction of preterm pre-eclampsia (<37 weeks), term pre-eclampsia (≥37 weeks), and any pre-eclampsia, which was derived and tested in a cohort of pregnant participants in the UK (Model 1). This model comprises maternal factors with measurements of mean arterial pressure, uterine artery pulsatility index, and serum placental growth factor (PlGF). The model was further retrained with adjustments for analyzers used for biochemical testing (Model 2). Discrimination was assessed by area under the receiver operating characteristic curve (AUC). The Delong test was used to compare the AUC of Model 1, Model 2, and the Fetal Medicine Foundation (FMF) competing risk model. RESULTS: The predictive performance of Model 1 was significantly lower than that of the FMF competing risk model in the prediction of preterm pre-eclampsia (0.82, 95% confidence interval [CI] 0.77-0.87 vs. 0.86, 95% CI 0.811-0.91, P = 0.019), term pre-eclampsia (0.75, 95% CI 0.71-0.80 vs. 0.79, 95% CI 0.75-0.83, P = 0.006), and any pre-eclampsia (0.78, 95% CI 0.74-0.81 vs. 0.82, 95% CI 0.79-0.84, P < 0.001). Following the retraining of the data with adjustments for the PlGF analyzers, the performance of Model 2 for predicting preterm pre-eclampsia, term pre-eclampsia, and any pre-eclampsia was improved with the AUC values increased to 0.84 (95% CI 0.80-0.89), 0.77 (95% CI 0.73-0.81), and 0.80 (95% CI 0.76-0.83), respectively. There were no differences in AUCs between Model 2 and the FMF competing risk model in the prediction of preterm pre-eclampsia (P = 0.135) and term pre-eclampsia (P = 0.084). However, Model 2 was inferior to the FMF competing risk model in predicting any pre-eclampsia (P = 0.024). CONCLUSION: This study has demonstrated that following adjustment for the biochemical marker analyzers, the predictive performance of the AI+ML prediction model for pre-eclampsia in the first trimester was comparable to that of the FMF competing risk model in an Asian population.

Sequential carotid Doppler study in acute stroke and its clinical correlation: A prospective study.

Objectives: Resistive index (RI) and pulsatility index (PI) assessed on carotid Doppler assess the hemodynamic status of cranial vasculature. They are related to the severity of stroke and help determine the overall outcome. This study was done to compare the hospital stay and stroke severity with RI and PI of both internal carotid arteries. Materials and Methods: Patients >18 years of age presenting within 48 h of anterior circulation stroke (either ischemic or hemorrhagic) were included. They were divided into two groups based on their length of stay (LOS). They were assessed clinically on days 1, 3, and 5, and underwent a carotid Doppler study on the same days. The Doppler parameters were correlated with the LOS and stroke severity for possible associations. Results: One hundred and one patients were included. Forty-seven patients had a favorable outcome based on LOS. In this group, significant decrease in RI and PI scores was seen from days 1 to 3. In patients with unfavorable outcome, there was a significant increase in PI on days 1-3 and days 1-5. The National Institutes of Health Stroke Scale decreased significantly from days 1 to 5 in favorable group. Conclusion: For those with an unfavorable outcome and prolonged LOS, PI continues to increase suggesting a failure of autoregulation. Carotid Doppler can be a simple bedside tool to predict outcome in patients with acute stroke.

Pulsatile Femoral Vein Doppler Pattern is a Parameter of Venous Congestion in ICU Patients.

OBJECTIVES: The aim of this study was to evaluate if the presence of a pulsatile femoral vein pattern is an indicator of venous congestion in the intensive care unit (ICU). DESIGN: Retrospective observational study. SETTING: Three medico-surgical university-affiliated ICUs. PARTICIPANTS: Adult patients who had an ultrasound evaluation at several time points during their ICU stay: at baseline (within 24 hours of admission to ICU), daily during their ICU stay, and within 24 hours before ICU discharge. INTERVENTIONS: At each time point, the hemodynamic, respiratory, and cardiac ultrasound parameters were recorded. The common femoral vein was studied with pulsed-wave Doppler at the level of the femoral trigonum, with high frequency (5-13 MHz) linear array vascular probe and venous vascular mode, in supine patients. MEASUREMENTS AND MAIN RESULTS: One hundred eight patients who underwent 400 ultrasound evaluations (3.7 ± 1 ultrasound evaluations per patient) during their ICU stay were included. Seventy-nine of 108 patients (73%) had a pulsatile femoral vein pattern at least at 1 time point. The multivariable mixed effects logistic regression model demonstrated an association among pulsatile femoral vein pattern, body mass index (OR: 0.91[95% CI 0.85-0.96], p = 0.002), inferior vena cava mean diameter (OR: 2.35 [95% CI 1.18-4.66], p = 0.014), portal vein pulsatility (OR: 2.3 [95% CI 1.2-4.4], p = 0.012), and congestive renal vein flow pattern (OR: 4.02 [95% CI 2.01-8.03], p < 0.001). The results were confirmed by principal component analysis. CONCLUSION: In the ICU, a pulsatile femoral vein pattern is associated with parameters of venous congestion, independently of the patient's volume status, and ventilatory treatment. These results suggest the femoral vein Doppler pulsatility as a parameter of congestion in ICU patients.

A longitudinal and cross-sectional study of placental circulation between normal and placental insufficiency pregnancies.

INTRODUCTION: To longitudinally and cross-sectionally study the differences in the uterine artery pulsatility index (UTPI), umbilical artery pulsatility index (UAPI) and placental vascularization indices (PVIs, derived from 3-dimensional power Doppler) between normal and placental insufficiency pregnancies throughout gestation. METHODS: UTPI, UAPI and PVI were measured 6 times at 4- to 5- week intervals from 11 to 13+6 weeks-36 weeks. Preeclampsia (PE) and fetal growth restriction (FGR) were defined as placental insufficiency. Comparisons of UTPI, UAPI and PVI between normal and insufficiency groups were performed by one-way repeated measures analysis of variance. RESULTS: A total of 125 women were included: monitored regularly from the first trimester to 36 weeks of gestation: 109 with normal pregnancies and 16 with placental insufficiency. Longitudinal study of the normal pregnancy group showed that UTPI and UAPI decreased significantly every 4 weeks, while PVIs increased significantly every 8 weeks until term. In the placental insufficiency group however, this decrease occurred slower at 8 weeks intervals and UTPI stabilized after 24 weeks. No significant difference was noted in PVIs throughout pregnancy. Cross-sectional study from different stages of gestation showed that UTPI was higher in the insufficiency group from 15 weeks onward and PVIs were lower after 32 weeks. DISCUSSION: Compared to high-risk pregnancies with normal outcome, UTPI and UAPI needed a longer time to reach a significant change in those with clinical confirmation of placental insufficiency pregnancies and no significant change was found in PVI throughout gestation. UTPI was the earliest factor in detecting adverse outcome pregnancies.

Assessment of arterial pulsatility of cerebral perforating arteries using 7T high-resolution dual-VENC phase-contrast MRI.

PURPOSE: Directly imaging the function of cerebral perforating arteries could provide valuable insight into the pathology of cerebral small vessel diseases (cSVD). Arterial pulsatility has been identified as a useful biomarker for assessing vascular dysfunction. In this study, we investigate the feasibility and reliability of using dual velocity encoding (VENC) phase-contrast MRI (PC-MRI) to measure the pulsatility of cerebral perforating arteries at 7 T. METHODS: Twenty participants, including 12 young volunteers and 8 elder adults, underwent high-resolution 2D PC-MRI scans with VENCs of 20 cm/s and 40 cm/s at 7T. The sensitivity of perforator detection and the reliability of pulsatility measurement of cerebral perforating arteries using dual-VENC PC-MRI were evaluated by comparison with the single-VENC data. The effects of temporal resolution in the PC-MRI acquisition and aging on the pulsatility measurements were investigated. RESULTS: Compared to the single VENCs, dual-VENC PC-MRI provided improved sensitivity of perforator detection and more reliable pulsatility measurements. Temporal resolution impacted the pulsatility measurements, as decreasing temporal resolution led to an underestimation of pulsatility. Elderly adults had elevated pulsatility in cerebral perforating arteries compared to young adults, but there was no difference in the number of detected perforators between the two age groups. CONCLUSION: Dual-VENC PC-MRI is a reliable imaging method for the assessment of pulsatility of cerebral perforating arteries, which could be useful as a potential imaging biomarker of aging and cSVD.

The association between discordant umbilical arterial resistance in growth-restricted fetuses and adverse outcomes.

BACKGROUND: Assessing the umbilical artery pulsatility index via Doppler measurements plays a crucial role in evaluating fetal growth impairment. OBJECTIVE: This study aimed to investigate perinatal outcomes associated with discordant pulsatility indices of umbilical arteries in fetuses with growth restriction. STUDY DESIGN: In this retrospective cohort study, all singleton pregnancies were included if their estimated fetal weight and/or abdominal circumference fell below the 10th percentile for gestational age (2017-2022). Eligible cases included singleton pregnancies with concurrent sampling of both umbilical arteries within 14 days of birth at the ultrasound evaluation closest to delivery. The exclusion criteria included births before 22 weeks of gestation, evidence of absent or reverse end-diastolic flow in either umbilical artery, and known fetal genetic or structural anomalies. The study compared cases with discordant umbilical artery pulsatility index values (defined as 1 umbilical artery pulsatility index at ≤95th percentile and the other umbilical artery pulsatility index at >95th percentile for gestational age) to pregnancies where both umbilical artery pulsatility indices had normal pulsatility index values and those with both umbilical arteries displaying abnormal pulsatility index values. The primary outcome assessed was the occurrence of composite adverse neonatal outcomes. Multivariable logistic regressions were performed, adjusting for relevant covariates. RESULTS: The study encompassed 1014 patients, including 194 patients (19.1%) with discordant umbilical artery pulsatility index values among those who had both umbilical arteries sampled close to delivery, 671 patients (66.2%) with both umbilical arteries having normal pulsatility index values, and 149 patients (14.7%) with both umbilical arteries exhibiting abnormal values. Pregnancies with discordant umbilical artery pulsatility index values displayed compromised sonographic parameters compared with those with both umbilical arteries showing normal pulsatility index values. Similarly, the number of abnormal umbilical artery pulsatility index values was associated with adverse perinatal outcomes in a dose-response manner. Cases with 1 abnormal (discordant) umbilical artery pulsatility index value showed favorable sonographic parameters and perinatal outcomes compared with cases with both abnormal umbilical artery pulsatility index values, and cases with both abnormal umbilical artery pulsatility index values showed worse sonographic parameters and perinatal outcomes compared with cases with discordant UA PI values. Multivariate analysis revealed that discordant umbilical artery pulsatility indices were significantly and independently associated with composite adverse perinatal outcomes, with an adjusted odds ratio of 1.75 (95% confidence interval, 1.24-2.47; P = .002). CONCLUSION: Evaluating the resistance indices of both umbilical arteries may provide useful data and assist in assessing adverse perinatal outcomes among fetuses with growth restriction.

Standing middle cerebral artery velocity predicts cognitive function and gait speed in older adults with cognitive impairment, and is impacted by sex differences.

Upright posture challenges the cerebrovascular system, leading to changes in middle cerebral artery velocity (MCAv) dynamics which are less evident at supine rest. Chronic alterations in MCAv have been linked to hypoperfusion states and the effect that this may have on cognition remains unclear. This study aimed to determine if MCAv and oscillatory metrics of MCAv (ex. pulsatility index, PI) during upright posture are i) associated with cognitive function and gait speed (GS) to a greater extent than during supine rest, and ii) are different between sexes. Beat-by-beat MCAv (transcranial Doppler ultrasound) and mean arterial pressure (MAP, plethysmography) were averaged for 30-seconds during supine-rest through a transition to standing for 53 participants (73±6yrs, 17 females). While controlling for age, multiple linear regressions predicting MoCA scores and GS from age, supine MCAv metrics, and standing MCAv metrics, were completed. Simple linear regressions predicting Montreal Cognitive Assessment (MoCA) score and GS from MCAv metrics were performed separately for females and males. Significance was set to p<0.05. Lower standing diastolic MCAv was a significant (p = 0.017) predictor of lower MoCA scores in participants with mild cognitive impairment, and this relationship only remained significant for males. Lower standing PI was associated with slower GS (p = 0.027, r=-0.306) in both sexes. Our results indicate a relationship between blunted MCAv and altered oscillatory flow profiles during standing, with lower MoCA scores and GS. These relationships were not observed in the supine position, indicating a unique relationship between standing measures of MCAv with cognitive and physical functions.

Successful management of HeartMate 3 in a patient with arrhythmogenic right ventricular cardiomyopathy.

The management of right heart failure during durable left ventricular assist device (LVAD) support remains an unsolved issue so far. We had a 44-year-old male patient who was diagnosed with arrhythmogenic right ventricular cardiomyopathy and received HeartMate 3 LVAD (Abbott, USA) implantation as a bridge-to-transplant indication. The pump speed was adjusted as low as 4500 rpm to avoid the left ventricular narrowing and interventricular septal leftward shift. Riociguat was administered to decrease the afterload of the right ventricle and increase the preload of the left ventricle, in addition to the combination of neurohormonal blockers. Frequent low-flow alarm events eventually disappeared after amlodipine administration, and he was successfully returned to work. We here present a unique management in a patient with right heart failure due to arrhythmogenic right ventricular cardiomyopathy during HeartMate 3 LVAD support.

Incidence and first trimester risk factors of stillbirth in Indonesia.

OBJECTIVES: To determine the incidence and the risk factors of stillbirth from maternal biophysical, ultrasound, and biochemical markers at 11-13 weeks of gestation in the Indonesian population. METHODS: This was a retrospective cohort study of pregnant women for first-trimester preeclampsia screening at 11-13 weeks of gestation in some clinics and hospital in Jakarta. Maternal characteristics and history, mean arterial pressure (MAP) measurement, uterine artery pulsatility index (UtA-PI) ultrasound, maternal ophthalmic peak ratio (Oph-PR) Doppler, and placental growth factor (PlGF) serum were collected during the visit. Stillbirth was classified into placental dysfunction-related when it occurred with preeclampsia or birth weight <10th percentile and non-placental dysfunction-related. Bivariate and multivariate logistic regression analyses were employed to determine the risk factors associated with stillbirth. RESULTS: Of 1,643 eligible participants, 13 (0.79 %) stillbirth cases were reported. More than half of the stillbirths (7) were placental dysfunction-related. After adjusted with maternal age, body mass index (BMI), and parity status, chronic hypertension (aOR (adjusted odds ratio)) 24.41, 95 % CI {confidence interval} 5.93-100.43), previous pregnancy with preeclampsia (aOR 15.79, 95 % CI 4.42-56.41), MAP >101.85 (aOR 26.67, 95 % CI 8.26-86.06), UtA-PI >1.90 (aOR 10.68, 95 % CI 2.34-48.58, and PlGF <28.77 pg/mL (aOR 18.60, 95 % CI 5.59-61.92) were associated with stillbirth. CONCLUSIONS: The incidence of stillbirth in the population is comparable to studies conducted in developed countries. Most routine variables assessed at the 11-13 weeks combined screening for preeclampsia are associated with the risk of stillbirth.

The role of the cerebroplacental ratio in predicting pregnancy outcomes at 40-42 gestational weeks: a prospective observational trial.

PURPOSE: The cerebroplacental ratio is a sonographic tool used to predict poor pregnancy outcomes. Data are insufficient regarding its use in postdate pregnancy. We evaluated the cerebroplacental ratio's prediction of unfavorable pregnancy outcomes in women at 40-42 weeks gestation with normal amniotic fluid index. METHODS: This prospective observational study included 101 women with low-risk singleton pregnancy and gestational age > 40 weeks who delivered in a university affiliated hospital during 2020-2021. The middle cerebral artery pulsatility index, the umbilical artery pulsatility index, and the cerebroplacental ratio, which is their quotient, were compared between women with favorable and unfavorable pregnancy outcomes. The latter included: meconium-stained amniotic fluid, cesarean or vacuum-assisted delivery due to pathological cardiotocography (category 2 or 3), 5-min Apgar score < 7, umbilical cord pH < 7.1, neonatal intensive care unit admission, and neonatal death. RESULTS: Fetal Doppler, performed at a median gestational age of 40.3 (40.0-41.6), did not differ between 75 (74.3%) women with favorable obstetrical outcomes and 26 (25.7%) with unfavorable outcomes. In multivariate analysis, advanced maternal age and a history of a cesarean section were correlated with unfavorable outcomes, while Doppler indices were not found to be predictive. Among women at 41-42 weeks' gestation, for those with intrapartum fetal monitor category 2-3 vs. category 1, the mean umbilical artery pulsatility index was higher: 0.92 ± 0.34 vs. 0.71 ± 0.11 (p = 0.044). CONCLUSION: According to the study results, fetal Doppler indices, including the cerebroplacental ratio, are not predictive of unfavorable outcome in women with pregnancies exceeding 40 weeks. Larger prospective studies are needed.