Peak Flow Velocity Research Articles

Cerebral blood flow response to cardiorespiratory oscillations in healthy humans

Dynamic cerebral autoregulation (CA) characterizes the cerebral blood flow (CBF) response to abrupt changes in arterial blood pressure (ABP). CA operates at frequencies below 0.15Hz. ABP regulation and probably CA are modified by autonomic nervous activity. We investigated the CBF response and CA dynamics to mild increase in sympathetic activity. Twelve healthy volunteers underwent oscillatory lower body negative pressure (oLBNP), which induced respiratory-related ABP oscillations at an average of 0.22Hz. We recorded blood velocity in the internal carotid artery (ICA) by Doppler ultrasound and ABP. We quantified variability and peak wavelet power of ABP and ICA blood velocity by wavelet analysis at low frequency (LF, 0.05-0.15Hz) and Mayer waves (0.08-0.12Hz), respectively. CA was quantified by calculation of the wavelet synchronization gamma index for the pair ABP-ICA blood velocity in the LF and Mayer wave band. oLBNP increased ABP peak wavelet power at the Mayer wave frequency. At the Mayer wave, ABP peak wavelet power increased by >70% from rest to oLBNP (p<0.05), while ICA blood flow velocity peak wavelet power was unchanged, and gamma index increased (from 0.49 to 0.69, p<0.05). At LF, variability in both ABP and ICA blood velocity and gamma index were unchanged from rest to oLBNP. Despite an increased gamma index at Mayer wave, ICA blood flow variability was unchanged during increased ABP variability. The increased synchronization during oLBNP did not cause less stable CBF or less active CA. Sympathetic activation seems to improve the mechanisms of CA.

Efficacy of Virtual Touch Quantification Technique for Differentiating Patients with Immunoglobulin A Nephropathy (IgAN) from Healthy Controls

Background: The virtual touch quantification (VTQ) using acoustic radiation force impulse (ARFI) is a type of ARFI technology, which has been widely used against many diseases. The sensitivity and specificity of VTQ in differentiating immunoglobulin A nephropathy (IgAN) patients from healthy controls remain unestablished. Objectives: The present study aimed to measure the VTQ values of renal parenchyma in patients with IgAN and to evaluate the efficacy of these values in distinguishing IgAN patients from healthy individuals. Patients and Methods: Ultrasound examinations were performed for the experimental and control groups. All routine ultrasound data, including the renal parenchymal thickness, renal volume, resistive index (RI) of interlobar renal arteries, and peak velocity of interlobar renal arteries, were collected. The VTQ values were measured in the middle and lower renal parenchyma using the VTQ technique. A receiver operating characteristic (ROC) curve was plotted to evaluate the efficacy of VTQ in differentiating IgAN patients from healthy individuals. Results: The VTQ values, RI values of interlobar arteries, and peak velocity of interlobar arteries were significantly different between patients with IgAN and the controls (2.14 ± 0.31 vs. 2.62 ± 0.24 m/s, 0.68 ± 0.05 vs. 0.63 ± 0.03 m/s, and 0.56 ± 0.59 vs. 0.60 ± 0.58 m/s; P &lt; 0.05 for all). The VTQ values were associated with the renal parenchymal thickness, peak flow velocity of interlobular arteries, and Lee’s grade (P &lt; 0.05 for all). The ROC curve analysis revealed that VTQ values might be used as a diagnostic method for differentiating IgAN patients (area under the curve [AUC] = 0.909) from healthy controls. Conclusion: The VTQ values significantly decreased in patients with IgAN and might play an important role in distinguishing IgAN patients from healthy individuals, with high sensitivity and specificity.

Dam failure analysis and flood disaster simulation under various scenarios.

The aim of this study is to analyze the effects of a possible dam failure under various scenarios and to generate a flood hazard map for two consecutive dams located in a study area with a dense-residential region and a heavy-traffic highway. Two consecutive dams consist of Elmalı 2, a concrete-buttress dam and Elmalı 1, an earth-fill gravity dam in the upstream and downstream, respectively. Hydrologic Engineering Center-River Analysis System (HEC-RAS) was used to develop a dam failure model. Dam failure scenarios were examined regarding three main criteria: the Breach Formation Time (BFT), the Number of Failed Buttresses (NFB) of Elmalı 2, and the Reservoir Volume Ratio (RVR) of Elmalı 1. Accordingly, flood peak depth (Hp), peak flow rate (Qp), peak velocity (vp), and time to reach the peak (tp) are discussed. The results showed that BFT and NFB of Elmalı 2 were highly effective on these values, whereas RVR of Elmalı 1 had no significant effect. Moreover, the total area affected by potential floods was calculated with a comparative areal change analysis using flood inundation and flood hazard maps obtained. Estimated damage costs indicate that in the worst-case scenario, more than 500 buildings will be affected in the region.

Pulmonary rehabilitation restores limb muscle mitochondria and improves the intramuscular metabolic profile.

Exercise, as the cornerstone of pulmonary rehabilitation, is recommended to chronic obstructive pulmonary disease (COPD) patients. The underlying molecular basis and metabolic process were not fully elucidated. Sprague-Dawley rats were classified into five groups: non-COPD/rest (n = 8), non-COPD/exercise (n = 7), COPD/rest (n = 7), COPD/medium exercise (n = 10), and COPD/intensive exercise (n = 10). COPD animals were exposed to cigarette smoke and lipopolysaccharide instillation for 90 days, while the non-COPD control animals were exposed to room air. Non-COPD/exercise and COPD/medium exercise animals were trained on a treadmill at a decline of 5° and a speed of 15 m/min while animals in the COPD/intensive exercise group were trained at a decline of 5° and a speed of 18 m/min. After eight weeks of exercise/rest, we used ultrasonography, immunohistochemistry, transmission electron microscopy, oxidative capacity of mitochondria, airflow-assisted desorption electrospray ionization-mass spectrometry imaging (AFADESI-MSI), and transcriptomics analyses to assess rectal femoris (RF). At the end of 90 days, COPD rats' weight gain was smaller than control by 59.48 ± 15.33 g (P = 0.0005). The oxidative muscle fibers proportion was lower (P < 0.0001). At the end of additional eight weeks of exercise/rest, compared to COPD/rest, COPD/medium exercise group showed advantages in weight gain, femoral artery peak flow velocity (Δ58.22 mm/s, 95% CI: 13.85-102.60 mm/s, P = 0.0104), RF diameters (Δ0.16 mm, 95% CI: 0.04-0.28 mm, P = 0.0093), myofibrils diameter (Δ0.06 μm, 95% CI: 0.02-0.10 μm, P = 0.006), oxidative muscle fiber percentage (Δ4.84%, 95% CI: 0.15-9.53%, P = 0.0434), mitochondria oxidative phosphorylate capacity (P < 0.0001). Biomolecules spatial distribution in situ and bioinformatic analyses of transcriptomics suggested COPD-related alteration in metabolites and gene expression, which can be impacted by exercise. COPD rat model had multi-level structure and function impairment, which can be mitigated by exercise.

Accuracy of Respiratory Variation in Inferior Vena Cava Diameter to Predict Fluid Responsiveness in Children Under Mechanical Ventilation.

Proper assessment of fluid responsiveness using accurate predictors is crucial to guide fluid therapy and avoid the serious adverse effects of fluid overload. The main objective of this study was to investigate the accuracy of respiratory variations in inferior vena cava diameter (∆IVC) to predict fluid responsiveness in mechanically ventilated children. This prospective single-center study included 32 children (median age and weight of 17months and 10kg, respectively) who received a fluid infusion of 10ml kg-1 of crystalloid solutions over 10min. ∆IVC and respiratory variation in aortic blood flow peak velocity (∆Vpeak) were determined over one controlled respiratory cycle before and after fluid loading. Thirteen (41%) participants were fluid-responders. ∆IVC, ∆Vpeak, stroke volume index, and cardiac index were found to be predictors of fluid responsiveness. However, the area under the ROC curve of ∆IVC was smaller when compared to ∆Vpeak (0.709 vs. 0.935, p < 0.012). The best cut-off values were 7.7% for ∆IVC (sensitivity, 69.2%; specificity 78.9%, positive predictive value, 69.2%; and negative predictive value, 78.9%) and 18.2% for ∆Vpeak (sensitivity, 84.6%; specificity, 89.5%; positive predictive value, 84.6%; negative predictive value, 89.5%). Changes in stroke volume were positively correlated with ∆IVC (ρ = 0.566, p < 0.001) and ∆Vpeak (ρ = 0.603, p < 0.001). A significant correlation was also found between changes in MAP and ∆Vpeak (ρ = 0.382; p = 0.031), but the same was not observed with ∆IVC (ρ = 0.011; p = 0.951). In conclusion, ∆IVC was found to have a moderate accuracy in predicting fluid responsiveness in mechanically ventilated children and is an inferior predictor when compared to ∆Vpeak.

Pre-Operative Four Dimensional Flow Sensitive Magnetic Resonance Imaging Assessment of Aortic Side Branches as a Method to Predict Risk of Type II Endoleak Resulting in Sac Enlargement After EVAR

To predict sac enlargement with type II endoleak (ELII) before endovascular aneurysm repair (EVAR) using four dimensional flow sensitive magnetic resonance imaging (4D flow MRI). A single centre retrospective analysis of prospectively collected data was conducted. Patients with an abdominal aortic aneurysm (AAA) who underwent EVAR between 2013 and 2019 were included. Aortic branches occluded pre-EVAR, and patients with endoleaks other than ELII were excluded. The aortic branch diameter, peak flow velocity (PFVe), and amplitude of the dynamics of flow volume (AFV) were measured in each aortic branch pre-EVAR. Total flow volume per minute (TFV/min), defined as the sum of AFV/min, was calculated in each case. According to computed tomography findings one year post-EVAR, the aortic branches and patients were divided into patent vessel and occluded vessel groups and sac expanding and non-expanding groups. PFVe, AFV/min, and TFV/min were analysed via receiver operating characteristic curve analysis. The patent aortic branches pre-EVAR (69 inferior mesenteric arteries [IMAs]; 249 lumbar arteries [LAs]) of 100 patients were included. Patent IMAs (n= 14) and occluded IMAs (n= 55), patent LAs (n= 23) and occluded LAs (n= 226), and expanding (n= 9) and non-expanding (n= 91) groups were compared, respectively. No statistically significant difference was observed in branch diameters (IMA; patent, 2.5 ± 0.8 mm, occluded, 2.5 ± 0.8 mm, p < .78 and LA; patent, 1.5 ± 0.3 mm, occluded, 1.5 ± 0.4 mm, p < .35). PFVe (IMA; patent, 262.6 mm2/sec, occluded, 183.4 mm2/sec and LA; patent, 142.6 mm2/sec, occluded, 47.7 mm2/sec) and AFV/min (IMA; patent, 8.4 mL, occluded, 5.2 mL and LA; patent, 4.2 mL, occluded, 1.4 mL) were higher in the patent vessel group (p < .050). TFV/min was statistically significantly higher in the expanding group (24.1 mL/min) than in the non-expanding group (7.0 mL/min) (p < .010). Pre-EVAR haemodynamic analyses using 4D flow MRI were useful to detect aortic branches responsible for ELII and to predict AAA cases with sac enlargement. This analysis suggests a new strategy for pre-EVAR aortic branch embolisation.

Diagnostic value of parameters derived from planar MUGA for detecting HFpEF in coronary artery disease patients

BackgroundIn recent years, heart failure with preserved ejection fraction (HFpEF) has received increasing clinical attention. To investigate the diagnostic value of diastolic function parameters derived from planar gated blood-pool imaging (MUGA) for detecting HFpEF in coronary atherosclerotic heart disease (coronary artery disease, CAD) patients.MethodsNinety-seven CAD patients with left ventricular ejection fraction ≥ 50% were included in the study. Based on the left ventricular end-diastolic pressure (LVEDP), the patients were divided into the HFpEF group (LVEDP ≥ 16 mmHg, 47 cases) and the normal LV diastolic function group (LVEDP < 16 mmHg, 50 cases). Diastolic function parameters obtained by planar MUGA include peak filling rate (PFR), filling fraction during the first third of diastole (1/3FF), filling rate during the first third of diastole (1/3FR), mean filling rate during diastole (MFR), and peak filling time (TPF). Echocardiographic parameters include left atrial volume index (LAVI), peak tricuspid regurgitation velocity (peak TR velocity), transmitral diastolic early peak inflow velocity (E), average early diastolic velocities of mitral annulars (average e′), average E/e′ ratio. The diastolic function parameters obtained by planar MUGA were compared with those obtained by echocardiography to explore the clinical value of planar MUGA for detecting HFpEF.ResultsThe Receiver-operating characteristic curve analysis of diastolic function parameters obtained from planar MUGA and echocardiography to detect HFpEF showed that: among the parameters examined by planar MUGA, the area under the curve (AUC) of PFR, 1/3FF, 1/3FR, MFR and TPF were 0.827, 0.662, 0.653, 0.663 and 0.809, respectively. Among the echocardiographic parameters, the AUCs for average e′, average E/e′ ratio, peak TR velocity, and LAVI values were 0.747, 0.706, 0.735, and 0.633. The combination of PFR and TPF showed an AUC of 0.856. PFR combined with TPF value demonstrated better predictive value than average e′ (Z = 2.020, P = 0.043).ConclusionDiastolic function parameters obtained by planar MUGA can be used to diagnose HFpEF in CAD patients. PFR combined with TPF was superior to the parameters obtained by echocardiography and showed good sensitivity and predictive power for detecting HFpEF.

PS-B02-12: EFFECTS OF ULTRAVIOLET LIGHT ON BLOOD PRESSURE AND LEFT VENTRICULAR FUNCTION

Ultraviolet light (UV), induces the activation of constitutive nitric oxide synthases, which produces nitric oxide (NO) of vascular relaxation factor. We hypothesize that UV-induced production of NO could have beneficial effect on hypertension. Twelve 6-week-old salt-sensitive hypertensive rats (Dahl-Iwai salt-sensitive DIS/Eis, Japan Society for the Study of Hypertension, Shizuoka, Japan) were used in this study. These rats were fed a high-salt diet containing 8%NaCl until 10 weeks of age and were then randomly divided into three groups i.e. baseline group (group non-UV), 0 h post UV (group UV 0 h), and 6 h post UV (group UV 6 h). The rats were irradiated with UVA and UVB lamps at an intensity of 100 mJ/cm2. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured by using tail-cuff method (BP-98A; Softron Co., Ltd., Tokyo, Japan). We evaluated left ventricular (LV) systolic and diastolic function using echocardiography with a 12 MHz transducer connected to a Xario ultrasound system (Toshiba Medical Systems Co., Tochigi, Japan). Interventricular septal thickness, LV posterior wall thickness, and LV end-diastolic and end-systolic diameters (LVDd and LVDs) were obtained from a short-axis view. Percent LV fractional shortening (%LVFS) was calculated as an index of LV systolic function. Peak flow velocities at the mitral level during rapid filling (E) and deceleration time (Dct), and peak early diastolic mitral annular velocity which indicate LV diastolic function, were measured using pulsed and tissue Doppler echocardiography. Histological skin tissue sections were fixed with 4% paraformaldehyde phosphate buffer solution for 24 h at room temperature, embedded in paraffin, sectioned transversely (thickness, 3 μm), and stained with hematoxylin-eosin to evaluate the impairments of skin. The SBP and DBP were lower in group UV 6 h than group non-UV and group UV 0 h. In contrast, there were no significant differences in heart rate and body weight among the three groups. The peak early diastolic mitral annular velocity was greater in group UV 6 h than group non-UV and group UV 0 h. LVDd, LVDs, and %LVFS were not significantly different among the three groups. We did not find the impairments in skin after UV irradiation. UVA and UVB may play an important role in regulating not only blood pressure but also LV function.

Ventricular dysfunction consequences of mechanical dyssynchrony in isolated complete right bundle branch block versus left bundle branch block.

Complete bundle branch block in individuals without structural heart disease is known as isolated complete bundle branch block. Isolated complete left bundle branch block (CLBBB) is correlated with ventricular dysfunction secondary to dyssynchrony; however, few studies have investigated isolated complete right bundle branch block (CRBBB), which was previously considered benign but was recently found to be associated with adverse cardiovascular outcomes. This study aimed to evaluate cardiac mechanical synchrony, and systolic and diastolic function in patients with isolated CRBBB and compare cardiac synchrony and function to patients with isolated CLBBB. This cross-sectional study was conducted at The First Hospital of China Medical University in Shenyang, China, from 2020 to 2021. A total of 44 isolated CRBBB patients, 44 isolated CLBBB patients, and 42 healthy subjects were enrolled in the study. Transthoracic echocardiography was performed in all subjects. Synchrony parameters, including the mechanical dispersion of the right ventricle [the standard deviation of time to the peak longitudinal strain of six right ventricular (RV) segments] and atrioventricular dyssynchrony parameter [the ratio of left ventricular (LV) diastolic filling time to the time interval between two adjacent R waves (RR interval) measured by tissue Doppler imaging]. RV and LV function were assessed by the global longitudinal strain (GLS) of six RV segments and 18 LV segments, and the ratio of the peak early diastolic flow velocity to annular velocity (E/e') of the tricuspid valve and mitral valve. Statistical analyses were performed, including an analysis of variance, Pearson correlation analysis, and linear regression analysis. Compared with the healthy subjects, the mechanical dispersion of the right ventricle was significantly increased, and ventricular function was impaired as evidenced by the decreased RV GLS and LV GLS, and the increased E/e' of the tricuspid valve and mitral valve in the isolated CRBBB patients (all P<0.001). Moreover, compared with the isolated CLBBB patients, the mechanical dispersion of the right ventricle and E/e' of the tricuspid valve were increased, and RV GLS was significantly reduced in the isolated CRBBB patients (all P<0.001). Mechanical dispersion of the right ventricle was independently associated with RV GLS [coefficient, 0.13; 95% confidence interval (CI): 0.004-0.26; P=0.04] in the isolated CRBBB patients. RV GLS (coefficient, 0.10; 95% CI: 0.01-0.20; P=0.03) and the ratio of the LV diastolic filling time to the RR interval measured (coefficient, -0.30; 95% CI: -0.53 to -0.07; P=0.01) were independent factors of LV GLS. The isolated CRBBB patients had impaired cardiac mechanical synchrony and ventricular function, and more decreased RV synchrony and function than the isolated CLBBB patients. Right intraventricular synchrony was independently associated with RV systolic dysfunction in patients with isolated CRBBB. Atrioventricular synchrony and RV systolic function were independently associated with the LV systolic function. Therefore, comprehensive evaluations of echocardiography results and close monitoring is required for isolated CRBBB patients.

Стресс-эхокардиография в диагностике кардиальной дисфункции в раннем постинфарктном периоде

The purpose — to assess the importance of stress echocardiography in identifying the nature and severity of cardiac dysfunction in patients with myocardial infarction. Material and methods.86 patients were examined at the outpatient stage of rehabilitation 6 weeks after myocardial infarction with primary coronary angioplasty with stenting. Results.Echocardiography revealed left ventricular hypertrophy (LVH) in 34 patients with myocardial infarction with concomitant arterial hypertension. Patients with LVH are characterized by more pronounced structural and functional LV remodeling, which is expressed in a lower LVEF and increased LVEDD, LVESVand LVEDV(p&lt;0.05). There were no differences in stroke volume between patients with and without LVH. The performed diastolic stress test in patients with LVH is characterized by significantly lower average early diastolic mitral annular velocity e` (7.6 vs. 9.3 cm/s, p&lt;0.01) without differences in the peak early transmitral Doppler flow velocity E (69.8 vs 78.0, p&gt;0.05) compared with patients without LVH. The revealed differences between patients with and without LVH are due to a higher post-exercise velocity e` in patients with normal LV geometry and a decrease in eccentric LVH subgroup. Conclusions.1) Patients with LVH in the early postinfarction period (6 weeks) have more pronounced LV systolic dysfunction, expressed in a decrease in LVEF and an increase in LVEDD, LVESV, LVEDV compared to patients without LVH.2) Left ventricular hypertrophy, in conditions of myocardial infarction, is associated with latent diastolic dysfunction, which is manifested by a lower average early diastolic mitral annular velocity e` after the stress-test.

Dynamic variables to predict fluid responsiveness in young children.

The evidence that dynamic variables predict fluid responsiveness in young children is limited by conflicting research results. Sixty patients, 1-3 years of age, undergoing major neurosurgery, received 10mL/kg of Ringer's solution over 10min after anesthesia induction. Respiratory variation in aortic blood flow peak velocity (∆Vpeak), plethysmographic variability index (PVI), FloTrac/Vigileo-derived stroke volume variation (SVV), dynamic arterial elastance (Eadyn ), and pulse pressure variation (PPV) were measured before and following fluid loading. An increase in the cardiac index (CI) of ≥10% following fluid loading identified fluid "responders." Twenty-six patients (43.3%) were fluid responders. Baseline ∆Vpeak was an excellent predictor of a CI increase following fluid loading with an area under the receiver operating characteristic curve (AUROC) of 0.982 (p < 0.001). The PVI showed fair diagnostic accuracy for CI-fluid responsiveness (AUROC 0.775, p < 0.001). Baseline ∆Vpeak and PVI cutoff values were 9.6% and 15%, respectively. PPV, SVV, and Eadyn were not predictors or were poor predictors for CI-fluid responsiveness (AUROC 0.669, 0.653, and 0.533, respectively). Volume-based PVI and ∆Vpeak showed acceptable reliability for fluid responsiveness prediction in young children undergoing major neurosurgery, whereas pressure-based SVV using FloTrac/Vigileo, Eadyn , and PPV did not.

Anticoagulation for mechanical heart valves during pregnancy: A case report and a literature review

Most previous treatment guidelines for pregnant women with mechanical heart valves recommend that low molecular weight heparin (LMWH) should be applied once every 12 hours and only as required to reach peak anti-Xa levels of approximately 1.0 to 1.2 IU/mL, but it is commonly associated with subtherapeutic trough levels, consequently with an inadequate level of anticoagulation. Our case report here together with a literature review suggests that dose-adjusted (Target trough anti-Xa levels of 0.6 to 0.7 IU/mL and with peak anti-Xa levels of around 1.0 to 1.2 IU/mL or < 1.5 IU/mL) LMWH should be given thrice daily throughout pregnancy. In addition, the findings of this rare case indicate that a combination of LMWH and warfarin is effective in the treatment of small thromboses in pregnancy. In the 1st trimester of pregnancy, a 28-year old pregnant female with a mechanical valve had a significant increase in the aortic valve flow rate and suspected mechanical valve thrombosis. The peak velocity of the pregnant female aortic mechanical valve increased, and mechanical valve thrombosis was suspected. We adjusted the enoxaparin sodium dose every 12 hours to 1 injection every 8 hours, with a total daily dose of 160 mL. Based on the original application of LMWH, warfarin (3 mg/day) was recommended. The pregnant woman delivered a live baby by cesarean section, and the peak flow velocity of the mechanical valve in the aortic position was reduced to nearly equivalent to the patient's pre-pregnancy status. The mother and the baby were in good health at the time of discharge. LMWH is administered twice daily, and anti-Xa trough levels are mostly in a subtherapeutic state, which may lead to insufficient anticoagulation and thrombosis. Dose-adjusted LMWH thrice daily throughout pregnancy is the recommended treatment for pregnant women with mechanical heart valves. The combination of LMWH and warfarin exhibited good efficacy for the treatment of small thromboses.

Right atrial pressure may be related to pulmonary artery acceleration time in echocardiography

Pulmonary artery pressure is commonly calculated from simplified Bernoulli equation involving peak velocity of tricuspid regurgitation (TRVmax). This calculation requires right atrial pressure (RAP) to be typically estimated from size and collapsibility of inferior vena cava (IVC) with inspiration and this estimation has its difficulties. Pulmonary artery pressure can also be calculated from pulmonary artery acceleration time (PACT) (time from onset to peak velocity of blood flow in right ventricular outflow tract).

FlowRAU-Net: Accelerated 4D Flow MRI of Aortic Valvular Flows With a Deep 2D Residual Attention Network.

In this work, we propose a novel deep learning reconstruction framework for rapid and accurate reconstruction of 4D flow MRI data. Reconstruction is performed on a slice-by-slice basis by reducing artifacts in zero-filled reconstructed complex images obtained from undersampled k-space. A deep residual attention network FlowRAU-Net is proposed, trained separately for each encoding direction with 2D complex image slices extracted from complex 4D images at each temporal frame and slice position. The network was trained and tested on 4D flow MRI data of aortic valvular flow in 18 human subjects. Performance of the reconstructions was measured in terms of image quality, 3-D velocity vector accuracy, and accuracy in hemodynamic parameters. Reconstruction performance was measured for three different k-space undersamplings and compared with one state of the art compressed sensing reconstruction method and three deep learning-based reconstruction methods. The proposed method outperforms state of the art methods in all performance measures for all three different k-space undersamplings. Hemodynamic parameters such as blood flow rate and peak velocity from the proposed technique show good agreement with reference flow parameters. Visualization of the reconstructed image and velocity magnitude also shows excellent agreement with the fully sampled reference dataset. Moreover, the proposed method is computationally fast. Total 4D flow data (including all slices in space and time) for a subject can be reconstructed in 69 seconds on a single GPU. Although the proposed method has been applied to 4D flow MRI of aortic valvular flows, given a sufficient number of training samples, it should be applicable to other arterial flows.

Relationship Between Subclinical Cardiovascular Diseases and Cardiac Morpho-Functional Parameters in Preclinical Stage A/B Heart Failure Adults with Type 2 Diabetes.

Type 2 diabetes mellitus (T2DM) is a common risk factor for cardiovascular disease which increases the risk of heart failure. This study aimed to determine whether clinical characteristics and subclinical cardiovascular disease (CVD) features are correlated with echocardiographic morpho-functional parameters of T2DM patients. Two hundred and fifty-five T2DM patients without a history of coronary heart disease were enrolled in this cross-sectional study. The demographic characteristics, glucose and lipid levels were assessed for each patient. Carotid ultrasonography and peripheral artery examination were performed to measure carotid intima-media thickness (cIMT), carotid plaque, ankle-brachial index (ABI), brachial artery pulse wave velocity (baPWV), and carotid-femoral pulse wave velocity (cfPWV). Furthermore, echocardiography was conducted to evaluate cardiac morphology and systolic and diastolic function. The relationship between clinical characteristics, subclinical cardiovascular diseases, and cardiac morpho-functional parameters was explored with the Pearson and stepwise multivariable linear regression analyses. A total of 255 subjects aged 18-80 years were enrolled in the study. Multiple regression analysis revealed that left ventricular mass index (LVMI) was correlated with age (β=0.463, p = 0.000) and systolic blood pressure (SBP) (β=0.179, p = 0.003). Relative wall thickness (RWT) was related to cfPWV (β=0.006, p = 0.007) and homeostasis model assessment of insulin resistance (HOMA-IR) (β=0.000, p = 0.036). In contrast, left ventricular ejection fraction (LVEF) was inversely related to cIMT (β=-0.925, p = 0.019). The ratio of the peak flow velocity of early diastole to atrial contraction (peak E/A) was correlated with age (β=-0.014, p = 0.000), diastolic blood pressure (DBP) (β=-0.006, p = 0.001) and cfPWV (β=-0.025, p = 0.044). In preclinical stage A/B heart failure adults with T2DM, age, BP, HOMA-IR, cfPWV and cIMT are correlated with cardiac morpho-functional parameters.

One stone hits two birds: transcatheter mitral valve edge-to-edge repair for hypertrophic obstructive cardiomyopathy and severe mitral regurgitation.

A 68-year-old woman presented with dyspnoea on exertion and intermittent palpitation followed by near fainting. The transthoracic echocardiography (TTE) revealed asymmetric myocardial hypertrophy with an interventricular septal wall thickness of 15.2 mm at diastole, and elongated anterior leaflet (Panel B) with systolic anterior motion (SAM; Panels A and C, right). Left ventricular outflow tract (LVOT) obstruction with a peak flow velocity (Vp) of 5.18 m/s and a peak pressure gradient (PPG) of 107 mmHg (Panel D) and severe eccentric mitral regurgitation (MR) were observed (Panel E). The transoesophageal echocardiography (TEE) showed MR mostly originated from A2 and A3 (Panel F). The patient was finally diagnosed as hypertrophic cardiomyopathy (HCM). After the Heart Team discussion and share decision-making, the patient then received transcatheter mitral valve edge-to-edge repair (TEER) with MitraClip system and a single XTR clip. The intraoperative TEE displayed residual trace MR (Panel J and TTE Panel I), abolishment of SAM phenomenon (Panel G, right), and an LVOT Vp of 1.84 m/s and PPG of 13 mmHg (Panel H). After the procedure, the left ventricular global longitudinal strain and circumferential strain also increased (pre-operation Panel C, left; post-operation Panel G, left). The patient got rid of prior symptoms immediately after the procedure, and she was then safely discharged home within a week.

Protein-protein interactions between RUNX3 and ZEB1 in chronic lung injury induced by methamphetamine abuse.

Methamphetamine (MA) is the most common and highly addictive substance abuse drug. Runt-related transcription factor 3 (RUNX3) and Zinc finger E-box-binding homeobox 1 (ZEB1) are associated with lung inflammation and fibrosis. However, the protein-protein interactions (PPIs) between RUNX3 and ZEB1 and its involvement in MA-induced chronic lung injury is still unclear. In this study, we evaluated lung injury using echocardiography, hematoxylin and eosin staining, and western blot analysis. The viability of alveolar epithelial cells (AECs) was assessed using cell counting kit-8. Molecular Operating Environment software, Search Tool for the Retrieval of Interacting Genes/Proteins database, co-immunoprecipitation, assay and confocal immunofluorescence assay were used to predict and identify the PPIs between RUNX3 and ZEB1. The expression of RUNX3 and ZEB1 were knockdown in AECs using siRNA. The results revealed that MA exposure increased the peak blood flow velocity of the pulmonary artery and the acceleration time of pulmonary artery blood flow. Further, exposure to MA also causes adhesion and fusion of the alveolar walls and altered AEC activity. A decrease in the expression of RUNX3 and an increase in the expression of ZEB1 and its downstream signaling molecules were observed on MA exposure. The PPIs between RUNX3 and ZEB1 were identified. Further, an increase in the protein binding rate of RUNX3-ZEB1 was observed in MA-induced lung injury. These results show interactions between RUNX3 and ZEB1. RUNX3 protects against lung injury; however, ZEB1 expression and the PPIs between ZEB1 and RUNX3 has deleterious effects on chronic lung injury induced by MA exposure. Our results provide a new therapeutic approach for the treatment of chronic lung injury due to MA exposure.

Carotid artery corrected flow time and respiratory variations of peak blood flow velocity for prediction of hypotension after induction of general anesthesia in elderly patients

BackgroundPostinduction hypotension is closely related to postoperative complications. Elderly patients with compromised cardiovascular compensatory reserve are more susceptible to hypotension after induction of general anesthesia. This study investigated whether the carotid artery corrected flow time (FTc) and respiratory variation of peak blood flow velocity in the common carotid artery (ΔVpeak) could predict postinduction hypotension in elderly patients.MethodsThis prospective observational study included elderly patients aged 65 to 75 who were scheduled for elective surgery under general anesthesia with ASA physical status class of I-II, without cardiovascular disease, hypertension, diabetes, or obesity. Anesthesia was induced by midazolam, sufentanil, and etomidate and was maintained by sevoflurane. The carotid artery FTc and ΔVpeak were measured by ultrasound before induction of anesthesia. Hemodynamic data were recorded before induction and then during the first 10 min after induction.ResultsNinety-nine patients were included in the final analysis, of whom 63 developed postinduction hypotension. The area under the receiver operating characteristic curves was 0.87 (0.78 to 0.93) for carotid artery FTc and 0.67 (0.56 to 0.76) for ΔVpeak, respectively. The optimal cutoff value for predicting postinduction hypotension was 379.1 ms for carotid artery FTc, with sensitivity and specificity of 72.2 and 93.7%, respectively. The best cutoff value was 7.5% for ΔVpeak, with sensitivity and specificity of 55.6 and 75.0%, respectively.ConclusionsThe carotid artery FTc is a reliable predictor of postinduction hypotension in elderly patients with ASA status of I or II, without cardiovascular disease, hypertension, diabetes, or obesity. Elderly patients with a carotid artery FTc less than 379.1 ms before anesthesia have a higher risk of postinduction hypotension.Trial registrationClinical Trial Registry on August 2nd, 2020 (www.chictr.org.cn; ChiCTR2000035190).

Role of carotid corrected flow time and peak velocity variation in predicting fluid responsiveness: a systematic review and meta-analysis.

Dynamic parameters used for predicting fluid responsiveness require special equipment and are minimally invasive. Therefore, recent interest in the use of carotid artery ultrasound parameters, such as carotid corrected flow time (FTc) and peak velocity variation (ΔVpeak) has grown. Therefore, we performed this systematic review and meta-analysis to assess the ability of carotid FTc and/or ΔVpeak to accurately predict fluid responsiveness. We searched the PubMed and Embase databases for articles evaluating the diagnostic accuracy of carotid FTc or ΔVpeak for predicting fluid responsiveness. Two independent authors performed the search and selected studies published until May 2022. The studies were assessed for the inclusion and exclusion criteria using Rayyan (Rayyan Systems Inc., 2022). Ten studies (n=438) that fulfilled the inclusion criteria were selected. Studies were divided into those assessing carotid FTc and those assessing carotid ΔVpeak. Five studies (six datasets) assessed FTc. The pooled sensitivity and specificity of carotid FTc were 0.76 and 0.88, respectively. The summary receiver operating characteristic (SROC) curve for carotid FTc had an area under the curve (AUC) of 0.9092, with a Q value of 0.8412. Seven studies calculated carotid ΔVpeak. The pooled sensitivity and specificity for ΔVpeak were 0.83 and 0.81, respectively. The SROC curve had an AUC of 0.8941 and a Q value of 0.8250. Our meta-analysis showed that both carotid FTc and ΔVpeak are useful for predicting fluid responsiveness in anesthesia and critical care settings with good specificity and sensitivity.

Abstract 10045: Higher Renal Vascular Resistance is Associated With Greater Body Mass Index in Children

Background: Obesity is associated with increased risk for cardiovascular and renal diseases, however, there has been little focus on renal vascular function. The purpose of this study is to assess renal vascular flow regulation and investigate their relation to cardiovascular risk factors in obese children. Methods: Noninvasive ultrasonographic measurements were made in 108 overweight/obese children aged 7 to 13 years (body mass index 18 to 33kg/m 2 ). Using color Doppler sonography, peak systolic (PSV), end-diastolic (EDV), and average peak flow (APV) velocities of renal artery were measured. Pulsatility index as a parameter of vascular resistance was calculated. Pulsatility index was defined as (PSV-EDV)/APV. Quantitative B-mode ultrasound scans were used to measure intima-media thickness and diameters of the common carotid artery. Plasma lipid concentrations, uric acid, homeostasis model assessment of insulin resistance, and high sensitivity C-reactive protein were assessed in the obese children. Results: Compared with overweight children with body mass index &lt;25 kg/m 2 , pulsatility index in obese children with body mass index≥25 kg/m 2 was significantly higher (1.24 ±0.13 vs. 1.13 ±0.14 cm/sec, p &lt; 0.01), because APV and EDV were significantly lower (35 ±3 vs. 38 ±7 cm/sec and 21± 3 vs. 25 ±5 cm/sec, p &lt;0.05, respectively), although PSV was not significantly different. Pulsatility index correlated significantly with body mass index (r =0.58, p &lt; 0.01), insulin (r = 0.24, p &lt; 0.05), homeostasis model assessment of insulin resistance (r =0.25, p &lt; 0.01), triglycerides (r = 0.26, p &lt; 0.01), uric acid (r = 0.22, p &lt; 0.05), systolic blood pressure (r = 0.31, p &lt; 0.01), and carotid intima-media thickness (r = 0.36, p&lt;0.01). Renal blood flow velocities did not correlate with high sensitivity C-reactive protein. Conclusions: The present study indicates that obesity can adversely affect renal vascular flow and resistance in children. Obesity-related insulin resistance may be a main risk factor for renal vascular flow changes. Obesity not only is a risk factor for later cardiovascular disease, but also is associated with significant impairment of renal arterial flow dynamics.