Systolic Flow Research Articles

Multimodal evaluation of the bloodstream alteration before and after combined revascularization for Moyamoya disease.

This study aimed to explore the hemodynamic changes before and after anastomosis in patients with Moyamoya disease (MMD) using multiple models. We prospectively enrolled 42 MMD patients who underwent combined revascularization. Intraoperative FLOW800 was performed before and after anastomosis, and parameters was collected, including maximum intensity, delay time, rise time, slope, blood flow index, and microvascular transit time (MVTT). Additionally, preoperative and postoperative hemodynamic parameters were measured using color Doppler ultrasonography (CDUS), including peak systolic velocity, end-diastolic velocity, resistance index (RI), pulsatility index (PI), and flow volume. Subsequently, the correlation between FLOW800 and CDUS parameters was explored. A total of 42 participants took part with an average age of 46.5 years, consisting of 19 men and 23 women. The analysis of FLOW800 indicated that both the delay time and rise time experienced a substantial decrease in both the recipient artery and vein. Additionally, the MVTT was found to be significantly reduced after the surgery (5.7 ± 2.2 s vs. 4.9 ± 1.6, p = 0.021). However, no statistically significant differences were observed among the other parameters. Similarly, all postoperative parameters in CDUS hemodynamics exhibited significant alterations in comparison to the preoperative values. The correlation analysis between FLOW800 and CDUS parameters indicated a significant association between MVTT and RI and PI, no significant relationships were found among the other parameters in the two groups. The hemodynamic outcomes of the donor and recipient arteries demonstrated significant changes following bypass surgery. The parameter of time appears to be more precise and sensitive in assessing hemodynamics using FLOW800. Multiple evaluations of hemodynamics could offer substantial evidence for perioperative management.

Triglyceride-glucose index and cervical vascular function: outpatient-based cohort study

ObjectivesThe purpose of this study was to investigate the correlation between triglyceride-glucose (TyG) index and cervical vascular function parameters in the general population without cerebrovascular disease.Materials and MethodsThis was a cross-sectional study that recruited a total of 1996 participants without cerebrovascular disease. TyG index was calculated based on fasting triglycerides and glucose. All patients were divided into two groups based on the median TyG index: the high TyG group and the low TyG group. The differences in basic clinical characteristics and neck vascular function parameters between the two groups of participants were compared, and then the correlation between TyG index and neck vascular function parameters was investigated.ResultsParticipants with a high TyG index had lower systolic, diastolic, and mean flow velocities in the basilar, vertebral, and internal carotid arteries compared with those with a low TyG index. Participants with a high TyG index had higher pulsatility index in the left vertebral artery and right internal carotid artery, but this difference was not observed in the basilar artery. In addition, TyG index was significantly negatively correlated with systolic, diastolic, and mean flow velocities in the basilar, vertebral, and internal carotid arteries, and the correlation remained after adjusting for confounding factors.ConclusionIn the general population, there was a well-defined correlation between TyG index and cervical vascular function parameters, and increased TyG index was independently associated with reduced cervical vascular blood flow velocity.

Effects of liraglutide on extraglycemic inflammatory markers and renal hemodynamic parameters in diabetic kidney disease (DKD).

Diabetic kidney disease (DKD) was the leading cause of kidney disease, which has been a crucial public health. Liraglutide is a drug, widely used for DKD treatment globally. However, the extraglycemic inflammatory markers and renal hemodynamic parameters of DKD patients treated with liraglutide has been not reported. In this study, 160 patients with early DKD were enrolled, 80 cases in the control group and 80 cases in the treatment group, respectively. The individuals in the control group were treated with metformin, while the individuals in the treatment group were treated with liraglutide and metformin for 3 months. The urinary microalbumin and urinary creatinine was measured to calculate the ratio (UACR), while the Doppler ultrasound were measured before and after treatment. After 3 months of treatment, body mass index (BMI), waist circumference (WC) and low-density lipoprotein cholesterol (LDL) in the treatment group were significantly decreased compared with before and after treatment in the control group; the levels of cystatin and UACR in treatment group were lower than before treatment and control group; The end-diastolic blood flow velocity (EDV) of renal artery and segment artery in treatment group was significantly higher than that before treatment and control group; The levels of CRP, TNF-α and IL-6 in the treatment group after treatment were lower than those before treatment and those in the control group. After 3 months of treatment, blood cystatin in the treatment group decreased significantly compared with before treatment and after treatment in the control group, with statistical significance After 3 months of treatment, the EDV of renal artery and renal segment in treatment group was significantly higher than that before treatment and control group, the peak systolic blood flow velocity (PSV) and EDV of renal interlobar artery in treatment group were significantly higher than those before treatment and control group. The resistance index (RI) was significantly lower than that before treatment and control group. Liraglutide can reduce inflammatory indicators, renal artery blood flow and renal function indicators in early DKD patients.

Is There A Structural Basis For Vasovagal Syncope? Cardiac Functions In Patients With Vasovagal Syncope

Aim: The pathophysiology of vasovagal syncope (VVS) is not completely understood. Some echocardiographic parameters have been defined to contribute to its pathophysiology. However. whether right atrial (RA) and right ventricular (RV) functions have any impact on development of VVS is not well known. In this study we aimed to evaluate the baseline echocardiographic parameters in patients with VVS with special focus on right ventricle and atrium functions.
 Material and methods: We evaluated the medical records of 42 patients with VVS and 41 age and sex matched healthy subjects. Patients with at least two syncopal attack and positive head-up-tilt test were enrolled in the study. All medical records of echocardiography and head-up-tilt test were obtained.
 Results: Among left ventricular function parameters, there were no significant difference between the groups. Right ventricle myocardial performance index (p= 0.003) and maximal pulmoner systolic flow velocity (PVmax) (p=0.03) were significantly differ between the groups. RAA was significantly larger (p=0.04) and the ratio of tricuspid filling velocities (E/A), (p=0.01) was significantly lower in VVS group. 
 Conclusions: The findings of the present study indicate a subtle right atrial diastolic dysfunction in patients with VVS. Decreased right atrial contribution to RV filling may cause a lower RV stroke volüme which explains the lower PVmax values in our VVS group. All together, those findings may serve for a tendency to low output states and hypotension as in VVS.

Asymmetry of flow in aortic root and its application in hypertrophic obstructive cardiomyopathy.

The aortic root (AR) performs sophisticated functions regulating the blood dynamics during the cardiac cycle. Such complex function depends on the nature of flow in the AR. Here, we investigate the potential of new quantitative parameters of flow asymmetry that could have clinical implications. We developed a MATLAB program to study the AR hemodynamics in each sinus of Valsalva using two-dimensional (2-D) cardiac magnetic resonance imaging during systole and particularly at peak systolic flow in 13 healthy volunteers and compared with 10 patients with hypertrophic obstructive cardiomyopathy (HOCM). We show that the effective area of the aortic jet in healthy volunteers is significantly higher at peak systolic flow and on average during systole. The flow asymmetry index, indicating how the jet is skewed away from the left coronary sinus (LCS), is small in healthy volunteers and much larger in HOCM at peak systole. The average of this index over systole is significantly more different between cohorts. Looking in more detail at the flow in the sinuses during systole, we show that the AR jet in healthy volunteers is more symmetrical, affecting the three sinuses almost equally, unlike the asymmetric AR jet in patients with HOCM that has decreased flow rate in the LCS and increased fractional area of backward flow in the LCS. The percentage of backward flow in the sinuses of Valsalva calculated over systole is a potential indicator of perturbed AR hemodynamics and the distribution of vortical flow and could be used as a measure of flow asymmetry.NEW & NOTEWORTHY The aortic root is a vital organ responsible for performing sophisticated functions to regulate the blood flow dynamics during the cardiac cycle. Such synchronized complex performance affects and is affected by the flow symmetry and type of flow reaching the aorta. Here, we report flow asymmetry in the aortic root which could have clinical implications, and we investigate the potential of various quantitative parameters as measures of flow asymmetry in hypertrophic obstructive cardiomyopathy.

Effectiveness of Duplex Doppler Sonography of Portal Vein as a Supplementary Tool in Diagnosis of Pediatric Appendicitis

Background Acute appendicitis is the most common surgical emergency in pediatric patients. Ultrasound is the preferred initial imaging modality to evaluate children with clinically- suspected appendicitis. whether by directly visualizing the inflamed appendix or by using secondary signs. However. rate of falsely negative or equivocal exams is still high, leading to a risk of complications from negative appendectomies as well as delayed diagnosis. Objective To evaluate the diagnostic accuracy of portal vein flow velocity and diameter in diagnosis of pediatric acute appendicitis Patients and Methods A cross-sectional study over the course of 6 months from June until November 2021. Portal vein diameter and peak systolic flow velocity were measured for 75 pediatric patients with clinically suspected appendicitis referred to radiodiagnosis department at Ain Shams University Hospitals for a pelvi-abdominal ultrasound examination. The largest appendix diameter secondary sonographic signs, and total leucocytic count were recorded if available. Results The mean age of the population was 112 ± 4.12 years (range. 3-18 years). Mean portal vein flow velocity was 38.94 ± 9.59 cm/s in the appendicitis group and 27.96 ± 6.98 cites in the non-appendicitis group. Median portal vein flow velocity was significantly higher in the appendicitis group (p < 0.001 with an overall diagnostic accuracy 82.1% at cut-off value of > 33.3 cm/sec. Mean portal vein diameter was 9.37±2.01 mm in the appendicitis group and 8.84 ± 2.19 mm in the non-appendicitis group, showing no statistically significant difference (P = 0.27). The presence of right iliac fossa echogenic fat was highly significant (P < 0.001) in predicting acute appendicitis. Conclusion The use of portal vein velocity as a supplementary tool improved the diagnostic performance and increased the sensitivity of ultrasound in diagnosing acute appendicitis. thus, decreasing the incidence of delayed appendectomies that have an increased risk of complications as well as decreasing the incidence of unnecessary appendectomies. Further studies are required to establish a comprehensive guideline to use it as a tool in ultrasound examinations of these patients.

Cerebrospinal Fluid Flow in Patients with Huntington's Disease.

Investigations of cerebrospinal fluid (CSF) flow aberrations in Huntington's disease (HD) are of growing interest, as impaired CSF flow may contribute to mutant Huntington retention and observed heterogeneous responsiveness to intrathecally administered therapies. We assessed net cerebral aqueduct CSF flow and velocity in 29 HD participants (17 premanifest and 12 manifest) and 51 age- and sex matched non-HD control participants using 3-Tesla magnetic resonance imaging methods. Regression models were applied to test hypotheses regarding: (i) net CSF flow and cohort, (ii) net CSF flow and disease severity (CAP-score), and (iii) CSF volume after correcting for age and sex. Group-wise analyses support a decrease in net CSF flow in HD (mean 0.14 ± 0.27 mL/min) relative to control (mean 0.32 ± 0.20 mL/min) participants (p = 0.02), with lowest flow in the manifest HD cohort (mean 0.04 ± 0.25 mL/min). This finding was explained by hyperdynamic CSF movement, manifesting as higher caudal systolic CSF flow velocity and higher diastolic cranial CSF flow velocity across the cardiac cycle, in HD (caudal flow: 0.17 ± 0.07 mL/s, cranial flow: 0.14 ± 0.08 mL/s) compared to control (caudal flow: 0.13 ± 0.06 mL/s, cranial flow: 0.11 ± 0.04 mL/s) participants. A positive correlation between cranial diastolic flow and disease severity was observed (p = 0.02). Findings support aqueductal CSF flow dynamics changing with disease severity in HD. These accelerated changes are consistent with changes observed over the typical adult lifespan, and may have relevance to mutant Huntington retention and intrathecally administered therapeutics responsiveness. ANN NEUROL 2023;94:885-894.

Effect of Ropivacaine Hydrochloride Nanoliposomes on Delayed Cerebral Vasospasm After Subarachnoid Hemorrhage in Rabbits

This research was aimed to investigate the effect of ropivacaine hydrochloride (RP-HCl) nanoliposome (NLP) on delayed cerebral vasospasm (DCVS) after subarachnoid hemorrhage (SAH) in rabbits. RP-HCl liposomes were prepared with RP-HCl, chloroform-ether, soybean phospholipid, dipalmitoyl phosphatidyl glycerol, and L-lysine 5% glucose solution by secondary emulsification, and blank NLP (without RP-HCl) was constructed at the same time. Additionally, an SAH model was also established by secondary blood injection into the large occipital pool. Forty New Zealand rabbits were randomly assigned into sham operation group (the injected liquid was 0.9% sodium chloride injection), control (Ctrl) group (the injected liquid was autologous blood and sodium chloride injection in sequence), no-load group (the injected liquid was autologous blood and blank liposomes in sequence), drug-loaded group (the injected liquid was autologous blood and RP-HCl NLP in sequence), and conventional group (the injected liquid was sodium chloride injection and ropivacaine in sequence), with eight rabbits in each group. The effects of RP-HCl NLP were analyzed through the changes in mean blood flow velocity (Vm), peak systolic blood flow velocity (Vp), neuron-specific enolase (NSE), S100B, diameter and apoptosis of the basilar artery (BA), vascular endothelial cell (EC) (VEC) endothelin-1 (ET-1), and endothelial nitric oxide synthase (eNOS). Results: the average particle size of RP-HCl NLP was 17.73±3.22 μm, and the average encapsulation efficiency was 86.40%. Relative to those before modeling, the Vm, Vp, NSE, and S100B levels in the BA of the five groups were increased on the 1st, 5th, and 10th days after modeling (P <0.05). In contrast to sham group, Vm, Vp, NSE, S100B, ET-1, and the apoptosis index were increased on the 1st, 5th, and 10th days after modeling in the other four groups, while the caliber and eNOS were decreased (P <0.05). The Vm, Vp, NSE, S100B, ET-1, and apoptosis index on the 1st, 5th, and 10th days after modeling in Ctrl and no-load groups were increased versus drug-loaded group, while the pipe diameter and eNOS were decreased (P <0.05). In conclusions, RP-HCl NLP can regulate the balance between ET-1 and eNOS, enhance neurological function, alleviate EC apoptosis, and reduce cerebral blood flow velocity to relieve DCVS after SAH.

Hemodynamic parameters impact the stability of distal stent graft-induced new entry

Stent graft-induced new entry tear (SINE) is a serious complication in aortic dissection patients caused by the stent-graft itself after thoracic endovascular aortic repair (TEVAR). The stability of SINE is a key indicator for the need and timing of reinterventions. This study aimed to understand the role of hemodynamics in SINE stability by means of computational fluid dynamics (CFD) analysis based on patient-specific anatomical information. Four patients treated with TEVAR who developed a distal SINE (dSINE) were included; two patients had a stable dSINE and two patients experienced expansion of the dSINE upon follow-up examinations. CFD simulations were performed on geometries reconstructed from computed tomography scans acquired upon early detection of dSINE in these patients. Computational results showed that stable dSINEs presented larger regions with low time-averaged wall shear stress (TAWSS) and high relative residence time (RRT), and partial thrombosis was observed at subsequent follow-ups. Furthermore, significant systolic antegrade flow was observed in the unstable dSINE which also had a larger retrograde flow fraction (RFF) on the SINE plane. In conclusion, this pilot study suggested that high RRT and low TAWSS may indicate stable dSINE by promoting thrombosis, whereas larger RFF and antegrade flows inside dSINE might be associated with its expansion.

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

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

A machine learning approach to predict cerebral perfusion status based on internal carotid artery blood flow

Background and objectiveCerebral blood flow (CBF), or perfusion, is a prerequisite for maintaining brain metabolism and normal physiological functions. Diagnosing and evaluating cerebral perfusion status is crucial to managing brain disease. However, cerebral perfusion imaging devices are complicated to operate, should be controlled by specialized technicians, are often large, and are usually installed in fixed places such as hospitals. It is significantly difficult for clinicians to obtain the cerebral perfusion status in time. Considering that CBF is mainly supplied by the internal carotid artery (ICA), this study proposes a cerebral perfusion status prediction model that can automatically quantify the level of cerebral perfusion in patients by modeling the association between ICA blood flow and cerebral perfusion. Materials and methodsForty-eight participants were enrolled in the study after screening. We collected participants’ ICA ultrasound and brain magnetic resonance imaging (MRI) data before and after dobutamine injection based on a rigorous experimental paradigm and built an ICA-cerebral perfusion datasetdd. Support vector machine (SVM), k-nearest neighbor (KNN), decision tree (DT), random forest (RF), gradient boosting decision tree (GBDT), and extreme gradient boosting (XGBOOST) were used for early prediction of cerebral perfusion status. The SHAP analysis was adopted to reveal the impact of interpretable predictions for each feature. ResultsThe XGBOOST model demonstrated the best overall classification performance with an accuracy of 78.01%, sensitivity of 96.67%, specificity of 98.23%, F1 score of 74.57%, Matthews correlation coefficient (MCC) of 62.17%, and area under the receiver operating characteristic curve (AUC) of 87.08%. Accelerated speed, peak systolic flow velocity, and resistance index of ICA blood flow are important factors for cerebral perfusion prediction. ConclusionsThe proposed method paves a new avenue for the study of predicting cerebral perfusion status automatically and providesv a noninvasive, real-time, and low-cost alternative to brain perfusion imaging. Moreover, this analysis identifies highly predictive features for the cerebral perfusion status and gives clinicians an intuitive understanding of the influence of key features. The prediction models can serve as an early warning tool that offers sufficient time for clinicians to take early intervention measures.

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

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

Cardiac Magnetic Resonance Imaging to Determine Single Ventricle Function in a Pediatric Population is Feasible in a Large Trial Setting: Experience from the Single Ventricle Reconstruction Trial Longitudinal Follow up

The Single Ventricle Reconstruction (SVR) Trial was a randomized prospective trial designed to determine survival advantage of the modified Blalock-Taussig-Thomas shunt (BTTS) vs the right ventricle to pulmonary artery conduit (RVPAS) for patients with hypoplastic left heart syndrome. The primary aim of the long-term follow-up (SVRIII) was to determine the impact of shunt type on RV function. In this work, we describe the use of CMR in a large cohort follow up from the SVR Trial as a focused study of single ventricle function. The SVRIII protocol included short axis steady-state free precession imaging to assess single ventricle systolic function and flow quantification. There were 313 eligible SVRIII participants and 237 enrolled, ages ranging from 10 to 12.5 years. 177/237 (75%) participants underwent CMR. The most common reasons for not undergoing CMR exam were requirement for anesthesia (n = 14) or ICD/pacemaker (n = 11). A total of 168/177 (94%) CMR studies were diagnostic for RVEF. Median exam time was 54 [IQR 40–74] minutes, cine function exam time 20 [IQR 14–27] minutes, and flow quantification time 18 [IQR 12–25] minutes. There were 69/177 (39%) studies noted to have intra-thoracic artifacts, most common being susceptibility artifact from intra-thoracic metal. Not all artifacts resulted in non-diagnostic exams. These data describe the use and limitations of CMR for the assessment of cardiac function in a prospective trial setting in a grade-school-aged pediatric population with congenital heart disease. Many of the limitations are expected to decrease with the continued advancement of CMR technology.

Aortic flow is associated with aging and exercise capacity.

Increased blood flow eccentricity in the aorta has been associated with aortic (AO) pathology, however, its association with exercise capacity has not been investigated. This study aimed to assess the relationships between flow eccentricity parameters derived from 2-dimensional (2D) phase-contrast (PC) cardiovascular magnetic resonance (CMR) imaging and aging and cardiopulmonary exercise test (CPET) in a cohort of healthy subjects. One hundred and sixty-nine healthy subjects (age 44 ± 13 years, M/F: 96/73) free of cardiovascular disease were recruited in a prospective study (NCT03217240) and underwent CMR, including 2D PC at an orthogonal plane just above the sinotubular junction, and CPET (cycle ergometer) within one week. The following AO flow parameters were derived: AO forward and backward flow indexed to body surface area (FFi, BFi), average flow displacement during systole (FDsavg), late systole (FDlsavg), diastole (FDdavg), systolic retrograde flow (SRF), systolic flow reversal ratio (sFRR), and pulse wave velocity (PWV). Exercise capacity was assessed by peak oxygen uptake (PVO2) from CPET. The mean values of FDsavg, FDlsavg, FDdavg, SRF, sFRR, and PWV were 17 ± 6%, 19 ± 8%, 29 ± 7%, 4.4 ± 4.2 mL, 5.9 ± 5.1%, and 4.3 ± 1.6 m/s, respectively. They all increased with age (r = 0.623, 0.628, 0.353, 0.590, 0.649, 0.598, all P < 0.0001), and decreased with PVO2 (r = -0.302, -0.270, -0.253, -0.149, -0.219, -0.161, all P < 0.05). A stepwise multivariable linear regression analysis using left ventricular ejection fraction (LVEF), FFi, and FDsavg showed an area under the curve of 0.769 in differentiating healthy subjects with high-risk exercise capacity (PVO2 ≤ 14 mL/kg/min). AO flow haemodynamics change with aging and predict exercise capacity. NCT03217240.

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

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

Doppler ocular ultrasound in patients with type 2 diabetes mellitus

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

The Dynamic Changes in Hemodynamics of the Forehead Flap During Tissue Expansion.

Background: The tissue expansion process brings changes in hemodynamics. Objective: To measure the change in vessel diameter, blood flow, and resistance in the blood vessels using ultrasound before, during, and after tissue expansion. Methods: Patients undergoing the embedment of a forehead expander from September 2021 to October 2022 were included. Hemodynamics parameters, including vessel diameter, blood flow velocity, and resistance index (RI) of the supraorbital artery (SOA), supratrochlear artery (STrA), and frontal branch of the superficial temporal artery (FBSTA), were measured with ultrasound before and 1, 2, 3, and 4 months after expansion. Results: Nine males and six females with ages ranging from 15 to 26 years (mean, 20 years) were included. After 4 months of expansion, the diameter of the STrA, SOA, and FBSTA increased significantly, the RI decreased significantly, and except the right SOA, peak systolic flow velocity increased significantly. Conclusion: The parameters of flap perfusion were significantly improved in the first 2 months of expansion and tended to stable values.

Precapillary pulmonary hypertension: RVOT systolic flow profile as a usuful tool

Abstract Funding Acknowledgements Type of funding sources: None. Introduction In patients (pts) with pulmonary hypertension (PH), right ventricular outflow tract (RVOT) systolic Doppler flow envelope is frequently abnormal, showing a mid-systolic notch that suggests elevation of pulmonary vascular resistance (PVR). Recent studies have demonstrated that other parameters, such as time-to-notch, may be indicators of elevated pulmonary artery pressures (PAP) and disease severity, conveying an important prognostic value. Purpose To evaluate the correlation between RVOT systolic flow morphology and hemodynamic parameters in pts with PH. Methods Retrospective, single-center study of consecutive pts diagnosed with pulmonary arterial hypertension (PAH) and chronic thromboembolic PH (CTEPH). We included pts who performed right heart catheterization (RHC) and transthoracic echocardiogram (TTE) within a six month period. RVOT systolic Doppler flow envelope was analyzed by measuring the ejection time (ET), time-to-notch (TN), pulmonary acceleration time (PAT), deceleration slope, pre- and post-notching velocity peak. Clinical, epidemiological, TTE and RHC data were recorded. For statistical analysis, Student's T tests, Chi-square and non-parametric tests were performed when appropriate. Results We included 79 pts, 42 with PAH (53%) and 37 with CTEPH (47%). 52 pts were women (66%) with a mean age of 58.06 ± 15.3 years. The mean follow-up (FUP) was 3.6±2.8 years. Most pts (92.3%) were symptomatic with a WHO functional status of II or III, despite specific PH treatment (69.4% PDE5 inhibitors, 63% endothelin receptor antagonists). In our analysis a higher TN correlated negatively with hemodynamic parameters such as mPAP (p = 0.02), PVR (p = 0.015), and mean right atrial pressure (mRAP), (p = 0.02). Similarly, pts with higher ET showed lower mPAP and sPAP in right ventricular catheterization (p = 0.044, p = 0.05 respectively). As previously reported, lower PAT showed a positive association with sPAP (p = 0.008), pulse pressure in pulmonary artery (p = 0.028), mRAP (p = 0.022), cardiac index (p = 0.01) and pulmonary vascular resistance (p = 0.04). When attempting to stratify TN and ET we noted a positive correlation with higher COMPERA score during FUP and lower clinical events, despite lack of clear statistical significance (p = 0.1). Regarding the remaining RVOT flow variables no statistically significant correlations were found. Conclusion This study shows that TN and ET accurately correlate with PAP and PVR, mirroring disease severity. Therefore, RVOT systolic flow profile is a non-invasive parameter that can be used as a valid tool when evaluating patients with PH.

False lumen flow dynamics and partial thrombosis in patients with chronic aortic dissection of the descending aorta: a 4D flow CMR study

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Spanish Ministry of Science, Innovation, and Universities Background Partial thrombosis of the false lumen (FL) in patients with chronic aortic dissection (AD) of the descending aorta has recently been associated with poor outcomes (1). However, four-dimensional phase-contrast cardiovascular magnetic resonance (4D flow CMR) studies analyzing flow dynamics and biomechanics in the FL and their relationship with partial thrombosis are lacking. Purpose This study aimed to compare FL flow dynamics and biomechanics between patients with non- and partially-thrombosed FL. Methods Patients with a chronic (&amp;gt;3 months after the acute event), non-thrombosed or partially-thrombosed FL in the descending aorta after an AD underwent an imaging follow-up including a magnetic resonance angiography (MRA) and a 4D flow CMR study. FL thrombosis was quantified as the ratio of thrombus volume and FL volume on MRA. Forward systolic and diastolic flow, and wall shear stress (WSS) were calculated at 8 equidistant planes covering the FL descending aorta from the pulmonary bifurcation to the diaphragmatic level, and averaged values were used (1,2). Maximum kinetic energy (KE), maximum acceleration and flow stasis were quantified in a volume covering the same region of the descending aorta (1). Aortic stiffness in the FL was assessed in terms of pulse wave velocity (PWV), which was calculated from the third supraortic trunk to the diaphragmatic level (3). Results Sixty-five patients with a complete imaging protocol were included in the study. The FL was non thrombosed in 34 patients and partially thrombosed in 31 patients, which presented with the 21 ± 13 % of the FL volume occupied by thrombus. Demographics and clinical data, and flow dynamic and biomechanical parameters of these patients are shown in Table 1. Partial thrombosis of the false lumen was associated with a reduction in the amount and energy of flow in the FL (reduced forward systolic flow, KE and acceleration (Figure 1B-D, respectively)), and a more stagnated flow in the FL (increased flow stasis (Figure 1E)). Axial WSS showed a tendency to be lower in the partial-thrombosis group compared to the no-thrombosis group (Figure 1F), while PWV were similar in both of them. Conclusion In patients with chronic AD of the descending aorta, false lumen axial wall shear stress, kinetic energy, and flow acceleration and stasis proved to be the main discriminators between no and partial thrombosis of the false lumen.

Left atrial function assessed by speckle tracking echocardiography as a marker of atrial reverse remodeling in patients with mitral regurgitation treated with transcatheter edge-to-edge repair

Abstract Funding Acknowledgements Type of funding sources: None. Background Left atrial reverse remodeling has been defined relying on changes in left atrial volume following specific procedures. Little is known about functional assessment of the left atrium by left atrial strain and left atrial emptying fraction (LAEF) following edge-to-edge mitral repair. Purpose The aim of this study is to assess left atrial function by speckle tracking echocardiography and changes in LAEF, as markers of atrial reverse remodeling, in patient with mitral regurgitation treated with edge-to-edge repair technique. Methods A total of 35 patients diagnosed with severe functional or organic mitral regurgitation who underwent trans-catheter edge-to-edge mitral valve repair were selected. Demographic, clinical and echocardiographic data were collected at the time of enrollment and after a minimum follow-up of six months. The primary endpoint was to assess if left atrial speckle tracking echocardiographic parameters (LASr, LAScd, LASct) and changes in LAEF were reliable indicators of left atrial reverse remodeling, defined as a reduction in indexed left atrial volume ≥ 15% with respect to basal assessment. Collaterally, we tried to identify clinical and standard echocardiographic parameters significantly related to atrial reverse remodeling. Changes between baseline and follow-up parameters were assessed using paired t-test. Results LASr, LASct and LAEF improved significantly in patients with left atrial remodeling during follow-up (LASr: 15,8%±8,43 vs 19,7%±12,22 - P 0,047; LASct: −6,4%±6,21 vs − 9,9%±8,52 - P 0,036; LAEF: 35,5%±14,17 vs 44,1%±15,17 - P 0,003). Collaterally, among all demographics, clinical and echocardiographic data, the absence of coronary artery disease, a systolic dominant pulmonary vein flow, as assessed with pulse-wave-Doppler after the repair, therapy with ACEi/ARB, lower increases in mitral valve pressure gradient after the procedure and lower pulmonary artery systolic pressure at discharge significantly correlated with reverse atrial remodeling. Conclusions In patients with mitral regurgitation treated with edge-to-edge repair, the assessment of left atrial function by speckle tracking echocardiography and left atrial emptying fraction correlates with atrial reverse remodeling, after a minimum follow-up of six months from the procedure. Further studies are needed to better clarify the impact of left atrial remodeling on strong clinical outcomes in patient with mitral regurgitation treated with edge-to-edge repair technique and the role of functional parameters in the definition of the optimal candidate and timing for the repair.