Aerobic Training and Ointment Effect on range of motion, von Willebrand factor, vascular endothelial factor and Femoral Artery Hemodynamics in Joint Contracture: A Rat Model.

OBJECTIVE: Using a rat model, we investigated the effect of multidisciplinary rehabilitation, including aerobic training and ointment, on the ROM, vWF, VEGF content, and femoral artery hemodynamics in rats with joint contracture. METHODS: A total of 44 Wistar rats were divided into the normal control group (NC, eight rats) and the experimental group (EG). A joint contracture model was established for the rats in the EG group by an external fixator. After fixator removal, 32 rats are further divided into the MC, SC, RE, and SR groups (n = 8). Before and after the 42 day intervention, the ROM, vWF, VEGF, PS, ED, and RI were measured using X-ray imaging, ELISA, and color Doppler ultrasound, respectively. RESULTS: After fixator removal, ROM for EG group was lower than that of the NC group (p < .01). After the intervention, ROM for the SR, RE, and SC groups was improved. The ROM for the SR group reached a similar value for NC group. vWF and VEGF levels in SR group were lower than in the MC, SC, and RE groups (p < .05), and had a similar value to the NC groups. PS value for SR and RE groups was higher than the MC and SC groups. The RI value for SR group was higher than that of NC and MC groups. CONCLUSION: Multidisciplinary rehabilitation used in this study can treat joint contracture synergistically. It improves the ROM of the joint, reduces the content of vWF and VEGF, and improves the femoral artery hemodynamics.

A Computational Pipeline to Investigate Longitudinal Blood Flow Changes in the Circle of Willis of Patients with Stable and Growing Aneurysms.

Changes in cerebral blood flow are often associated with the initiation and development of different life-threatening medical conditions including aneurysm rupture and ischemic stroke. Nevertheless, it is not fully clear how haemodynamic changes in time across the Circle of Willis (CoW) are related with intracranial aneurysm (IA) growth. In this work, we introduced a novel reduced-order modelling strategy for the systematic quantification of longitudinal blood flow changes across the whole CoW in patients with stable and unstable/growing aneurysm. Magnetic Resonance Angiography (MRA) images were converted into one-dimensional (1-D) vessel networks through a semi-automated procedure, with a level of geometric reconstruction accuracy controlled by user-dependent parameters. The proposed pipeline was used to systematically analyse longitudinal haemodynamic changes in seven different clinical cases. Our preliminary simulation results indicate that growing aneurysms are not necessarily associated with significant changes in mean flow over time. A concise sensitivity analysis also shed light on which modelling aspects need to be further characterized to have reliable patient-specific predictions. This study poses the basis for investigating how time-dependent changes in the vasculature affect the haemodynamics across the whole CoW in patients with stable and growing aneurysms.

Differences in blood flow dynamics between balloon- and self-expandable valves in patients with aortic stenosis undergoing transcatheter aortic valve replacement.

BACKGROUND: The differences in pre- and early post-procedural blood flow dynamics between the two major types of bioprosthetic valves, the balloon-expandable valve (BEV) and self-expandable valve (SEV), in patients with aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR), have not been investigated. We aimed to investigate the differences in blood flow dynamics between the BEV and SEV using four-dimensional flow cardiovascular magnetic resonance (4D flow CMR). METHODS: We prospectively examined 98 consecutive patients with severe AS who underwent TAVR between May 2018 and November 2021 (58 BEV and 40 SEV) after excluding those without CMR because of a contraindication, inadequate imaging from the analyses, or patients' refusal. CMR was performed in all participants before (median interval, 22 [interquartile range (IQR) 4-39] days) and after (median interval, 6 [IQR 3-6] days) TAVR. We compared the changes in blood flow patterns, wall shear stress (WSS), and energy loss (EL) in the ascending aorta (AAo) between the BEV and SEV using 4D flow CMR. RESULTS: The absolute reductions in helical flow and flow eccentricity were significantly higher in the SEV group compared in the BEV group after TAVR (BEV: - 0.22 ± 0.86 vs. SEV: - 0.85 ± 0.80, P < 0.001 and BEV: - 0.11 ± 0.79 vs. SEV: - 0.50 ± 0.88, P = 0.037, respectively); there were no significant differences in vortical flow between the groups. The absolute reduction of average WSS was significantly higher in the SEV group compared to the BEV group after TAVR (BEV: - 0.6 [- 2.1 to 0.5] Pa vs. SEV: - 1.8 [- 3.5 to - 0.8] Pa, P = 0.006). The systolic EL in the AAo significantly decreased after TAVR in both the groups, while the absolute reduction was comparable between the groups. CONCLUSIONS: Helical flow, flow eccentricity, and average WSS in the AAo were significantly decreased after SEV implantation compared to BEV implantation, providing functional insights for valve selection in patients with AS undergoing TAVR. Our findings offer valuable insights into blood flow dynamics, aiding in the selection of valves for patients with AS undergoing TAVR. Further larger-scale studies are warranted to confirm the prognostic significance of hemodynamic changes in these patients.

Reduced tubuloglomerular feedback activity and absence of its synchronization in a connexin40 knockout rat.

Introduction: Tubuloglomerular feedback (TGF) is the negative feedback component of renal blood flow (RBF) autoregulation. Neighbouring nephrons often exhibit spontaneous TGF oscillation and synchronization mediated by endothelial communication, largely via connexin40 (Cx40). Methods: We had a knockout (KO) rat made that lacks Cx40. One base pair was altered to create a stop codon in exon 1 of Gja5, the gene that encodes Cx40 (the strain is WKY-Gja55em1Mcwi). Blood pressure (BP)-RBF transfer functions probed RBF dynamics and laser speckle imaging interrogated the dynamics of multiple efferent arterioles that reach the surface (star vessels). Results: The distribution of wild type (WT), heterozygote, and KO pups at weaning approximated the Mendelian ratio of 1:2:1; growth did not differ among the three strains. The KO rats were hypertensive. BP-RBF transfer functions showed low gain of the myogenic mechanism and a smaller TGF resonance peak in KO than in WT rats. Laser speckle imaging showed that myogenic mechanism had higher frequency in KO than in WT rats, but similar maximum spectral power. In contrast, the TGF frequency was similar while peak power of its oscillation was much smaller in KO than in WT rats. In WT rats, plots of instantaneous TGF phase revealed BP-independent TGF synchronization among star vessels. The synchronization could be both prolonged and widespread. In KO rats TGF synchronization was not seen, although BP transients could elicit short-lived TGF entrainment. Discussion: Despite the reduced TGF spectral power in KO rats, there was sufficient TGF gain to induce oscillations and therefore enough gain to be effective locally. We conclude that failure to synchronize is dependent, at least in part, on impaired conducted vasomotor responses.

Direct Blood Cell Flow Imaging in Microvascular Networks.

Blood flow dynamics in microvascular networks are intimately related to the health of tissues and organs. While numerous imaging modalities and techniques have been developed to assess blood flow dynamics for various applications, their utilization has been hampered by limited imaging speed and indirect quantification of blood flow dynamics. Here, direct blood cell flow imaging (DBFI) is demonstrated that provides visualization of individual motions of blood cells over a field of 0.71 mm × 1.42 mm with a time resolution of 0.69 ms (1450 frames s-1 ) without using any exogenous agents. DBFI enables precise dynamic analysis of blood cell flow velocities and fluxes in various vessels over a large field, from capillaries to arteries and veins, with unprecedented time resolution. Three exemplary applications of DBFI, quantification of blood flow dynamics of 3D vascular networks, analysis of heartbeat induced blood flow dynamics, and analysis of blood flow dynamics of neurovascular coupling, illustrate the potential of this new imaging technology.

A novel nonlinear analysis of blood flow dynamics applied to the human lung.

The spatial/temporal dynamics of blood flow in the human lung can be measured noninvasively with magnetic resonance imaging (MRI) using arterial spin labeling (ASL). We report a novel data analysis method using nonlinear prediction to identify dynamic interactions between blood flow units (image voxels), potentially providing a probe of underlying vascular control mechanisms. The approach first estimates the linear relationship (predictability) of one voxel time series with another using correlation analysis, and after removing the linear component, it estimates the nonlinear relationship with a numerical mutual information approach. Dimensionless global metrics for linear prediction (FL) and nonlinear prediction (FNL) represent the average amplitude of fluctuations in one voxel estimated by another voxel, as a percentage of the global average voxel flow. A proof-of-principle test of this approach analyzed experimental data from a study of high-altitude pulmonary edema (HAPE), providing two groups exhibiting known differences in vascular reactivity. Subjects were mountaineers divided into HAPE-susceptible (S, n = 4) and HAPE-resistant (R, n = 5) groups based on prior history at high altitudes. Dynamic ASL measurements in the lung in normoxia (N, [Formula: see text] = 0.21) and hypoxia (H, [Formula: see text] = 0.13 ± 0.01) were compared. The nonlinear prediction metric FNL decreased with hypoxia [7.4 ± 1.3 (N) vs. 6.3 ± 0.7 (H), P = 0.03] and was significantly different between groups [7.4 ± 1.2 (R) vs. 6.2 ± 14.1 (S), P = 0.03]. This proof-of-principle test demonstrates that this nonlinear analysis approach applied to ASL data is sensitive to physiological effects even in small subject cohorts, and it potentially can be used in a wide range of studies in health and disease in the lung and other organs.NEW & NOTEWORTHY Pulmonary blood flow varies both spatially and temporally. We describe a novel technique to uncover nonlinear interactions in dynamic images of pulmonary blood flow measured using MRI, based on mutual information between the flow fluctuations in different imaging voxels. In a proof-of-principle study, we show that the proposed metric of nonlinear interactions was sufficiently sensitive to detect a difference between small cohorts of subjects susceptible to high-altitude pulmonary edema (HAPE) and subjects resistant to HAPE.

Cerebral hemodynamic monitoring and risk factors of severe intraventricular hemorrhage in extremely and very preterm infants: a case control study / 中国新生儿科杂志

Objective:To study the risk factors, cerebral hemodynamics and clinical outcomes of extremely and very preterm infants with severe intraventricular hemorrhage (IVH).Methods:From January 2019 to December 2019, premature infants with gestational age (GA) <32 w admitted to our hospital were assigned into severe IVH group and non-severe IVH group. Risk factors for severe IVH were analyzed. According to clinical outcomes, severe IVH group was further assigned into improvement subgroup and no-improvement subgroup. Cerebral hemodynamic parameters were compared between the two groups.Results:A total of 346 eligible neonates were enrolled in this study. The incidence of severe IVH was 11.0% (38 cases). The incidences of Grade Ⅲ and Ⅳ IVH were 8.7% (30/346) and 2.3% (8/346), respectively. Multivariate logistic regression analysis showed that CA < 28 w ( OR=4.365, 95% CI 1.055~18.054), 5 min Apgar score ≤7 ( OR=8.749, 95% CI 2.214~36.042), chorioamnionitis ( OR=3.245, 95% CI 1.127～9.344), PaCO 2 fluctuation within 1 h >25 mmHg ( OR=7.728, 95% CI 1.738~80.907) and vasoactive drugs usage ( OR=10.883, 95% CI 3.746~31.621) were the risk factors of severe IVH. 20 cases in severe IVH group were improved at discharge and 12 cases showed no improvement at discharge. Improvement subgroup showed quicker reduction of the middle cerebral artery flow resistance and faster recovery of the mean flow velocity than the no-improvement subgroup. Conclusions:GA <28 w, 5 min Apgar score ≤7, chorioamnionitis, PaCO 2 fluctuation within 1 h >25 mmHg and vasoactive drugs usage are risk factors of severe IVH in extremely and very preterm infants. Cerebral hemodynamic monitoring may provide initial assessment for the clinical outcomes for severe IVH.

Blood flow dynamics with four-dimensional flow cardiovascular magnetic resonance in patients with aortic stenosis before and after transcatheter aortic valve replacement.

BACKGROUND: Pre- and post-procedural hemodynamic changes which could affect adverse outcomes in aortic stenosis (AS) patients who undergo transcatheter aortic valve replacement (TAVR) have not been well investigated. Four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) enables accurate analysis of blood flow dynamics such as flow velocity, flow pattern, wall shear stress (WSS), and energy loss (EL). We sought to examine the changes in blood flow dynamics of patients with severe AS who underwent TAVR. METHODS: We examined 32 consecutive severe AS patients who underwent TAVR between May 2018 and June 2019 (17 men, 82 ± 5 years, median left ventricular ejection fraction 61%, 6 self-expanding valve), after excluding those without CMR because of a contraindication or inadequate imaging from the analyses. We analyzed blood flow patterns, WSS and EL in the ascending aorta (AAo), and those changes before and after TAVR using 4D flow CMR. RESULTS: After TAVR, semi-quantified helical flow in the AAo was significantly decreased (1.4 ± 0.6 vs. 1.9 ± 0.8, P = 0.002), whereas vortical flow and eccentricity showed no significant changes. WSS along the ascending aortic circumference was significantly decreased in the left (P = 0.038) and left anterior (P = 0.033) wall at the basal level, right posterior (P = 0.011) and left (P = 0.010) wall at the middle level, and right (P = 0.012), left posterior (P = 0.019) and left anterior (P = 0.028) wall at the upper level. EL in the AAo was significantly decreased (15.6 [10.8-25.1 vs. 25.8 [18.6-36.2]] mW, P = 0.012). Furthermore, a significant negative correlation was observed between EL and effective orifice area index after TAVR (r = - 0.38, P = 0.034). CONCLUSIONS: In severe AS patients undergoing TAVR, 4D flow CMR demonstrates that TAVR improves blood flow dynamics, especially when a larger effective orifice area index is obtained.

Vortex dynamics and transport phenomena in stenotic aortic models using Echo-PIV.

Atherosclerosis is the most fatal cardiovascular disease. As disease progresses, stenoses grow inside the arteries blocking their lumen and altering blood flow. Analysing flow dynamics can provide a deeper insight on the stenosis evolution. In this work we combined Eulerian and Lagrangian descriptors to analyze blood flow dynamics and fluid transport in stenotic aortic models with morphology, mechanical and optical properties close to those of real arteries. To this end, vorticity, particle residence time (PRT), particle's final position (FP) and finite time Lyapunov's exponents (FTLE) were computed from the experimental fluid velocity fields acquired using ultrasonic particle imaging velocimetry (Echo-PIV). For the experiments, CT-images were used to create morphological realistic models of the descending aorta with 0%, 35% and 50% occlusion degree with same mechanical properties as real arteries. Each model was connected to a circuit with a pulsatile programmable pump which mimics physiological flow and pressure conditions. The pulsatile frequency was set to ≈0.9 Hz (55 bpm) and the upstream peak Reynolds number (Re) was changed from 1100 to 2000. Flow in the post-stenotic region was composed of two main structures: a high velocity jet over the stenosis throat and a recirculation region behind the stenosis where vortex form and shed. We characterized vortex kinematics showing that vortex propagation velocity increases withRe. Moreover, from the FTLE field we identified Lagrangian coherent structures (i.e. material barriers) that dictate transport behind the stenosis. The size and strength of those barriers increased withReand the occlusion degree. Finally, from the PRT and FP maps, we showed that independently ofRe, the same amount of fluid remains on the stenosis over more than a pulsatile period.

Effect of sinusoidal leg cycling exercise period on brachial artery blood flow dynamics in humans.

PURPOSE: To quantify the dynamics of blood flow in brachial artery (BF-BA) in response to sinusoidal work rate (WR) leg cycling exercises of 2-, 4-, and 6-min periods and to examine their relationship with the forearm skin blood flow (SBF). METHODS: Seven healthy young male subjects performed upright leg ergometer exercise with a constant WR (mean sinusoidal WR) for 30 min followed by sinusoidal WR exercise of three different periods (number of repetitions): 2 min (7), 4 min (4), and 6 min (3). The WR fluctuated from 20 W to a peak WR corresponding to 60% peak oxygen uptake (VO2). We continuously measured pulmonary gas exchange, heart rate (HR), blood velocity and cross-sectional area of BA, and forearm SBF and sweating rate (SR). RESULTS: All variables were followed by the sinusoidal WR. The phases of the variables for gas exchange and central circulation, such as VO2 and HR with WR forcing were similar (e.g., phase shift (θ) in HR [°]: 2 min, 60 ± 7; 4 min, 45 ± 10; 6 min, 37 ± 8; mean ± SD) to previous study results, that is, a longer period showed a shorter θ and larger amplitude of responses. Contrarily, the BF-BA response showed anti-phase (approximately 180°) regardless of the period, whereas the θ of forearm SBF and SR were similar to gas exchange and central circulation. CONCLUSIONS: Inactive limb BF-BA during sinusoidal leg cycling exercise was out of phase relative to the regulation of O2-delivery to active muscles and thermoregulation. The response of BF-BA seems to not always reflect the response of forearm SBF in the downstream area.

Effect of diastolic dysfunction on intraventricular velocity behavior in early diastole by flow mapping.

Intraventricular velocity distribution reflects left ventricular (LV) diastolic function and can be measured non-invasively by flow mapping technologies. We designed our study to compare intraventricular velocities and gradients, obtained by vector flow mapping (VFM) technology during early diastole in consecutive patients diagnosed with mild and advanced diastolic dysfunction at echocardiography and a control group with a purpose to validate the hypothesis of relationship between new parameters and severity of diastolic dysfunction and conventional markers of elevated LV filling pressure. Two-dimensional streamline fields were obtained using VFM technology in 121 subjects (57 with normal diastolic function, 38 with mild diastolic dysfunction and 26 with advanced diastolic dysfunction). We measured several velocities and calculated a gradient along the selected streamline, which we compared between groups and correlated them with conventional echocardiographic parameters. Apical intraventricular velocity gradient (GrIV) was the lowest in control group, followed by mild and advanced diastolic dysfunction groups (5.3 ± 1.9 vs. 6.8 ± 2.5 vs. 13.6 ± 5.0/s, p < 0.001) and showed good correlation with E/e' (r = 0.751, p < 000.1). GrIV/e' ratio was the strongest single predictor of severity of diastolic dysfunction. Different degrees of diastolic dysfunction affect the Intraventricular velocity behavior during early diastole obtained by VFM. GrIV could discriminate between groups with different levels of diastolic dysfunction and was closely associated with classical echocardiographic indices of elevated LV filling pressure. GrIV/e' ratio has a potential to become a single parameter needed to assess left ventricular diastolic function.

Assessing test-retest reliability of phase contrast MRI for measuring cerebrospinal fluid and cerebral blood flow dynamics.

PURPOSE: Pathological states occur when cerebrospinal fluid (CSF) and cerebral blood flow (CBF) dynamics become dysregulated in the brain. Phase-contrast MRI (PC-MRI) is a noninvasive imaging technique that enables quantitative measurements of CSF and CBF flow. While studies have validated PC-MRI as an imaging technique for flow, few studies have evaluated its reliability for CSF and CBF flow parameters commonly associated with neurological disease. The purpose of this study was to evaluate test-retest reliability at the cerebral aqueduct (CA) and C2-C3 area using PC-MRI to assess the feasibility of investigating CSF and CBF flow dynamics. METHODS: This study was performed on 27 cognitively normal young adults (ages 20-35 years). Flow data was acquired on a 3T Siemens Prisma using a 2D cine-PC pulse sequence. Three consecutive flow measurements were acquired at the CA and C2-C3 area. Intraclass correlation coefficient (ICC) and coefficient of variance (CV) were used to evaluate intrarater, inter-rater, and test-retest reliability. RESULTS: Among the 26 flow parameters analyzed, 22 had excellent reliability (ICC > 0.80), including measurements of CSF stroke volume, flush peak, and fill peak, and 4 parameters had good reliability (ICC 0.60-0.79). 16 flow parameters had a mean CV ≤ 10%, 7 had a CV ≤ 15%, and 3 had a CV ≤ 30%. All CSF and CBF flow measurements had excellent inter-rater and intrarater reliability (ICC > 0.80). CONCLUSION: This study shows that CSF and CBF flow can be reliably measured at the CA and C2-C3 area using PC-MRI, making it a promising tool for studying flow dynamics in the central nervous system.

Quantifying blood flow dynamics during cardiac development: demystifying computational methods.

Blood flow conditions (haemodynamics) are crucial for proper cardiovascular development. Indeed, blood flow induces biomechanical adaptations and mechanotransduction signalling that influence cardiovascular growth and development during embryonic stages and beyond. Altered blood flow conditions are a hallmark of congenital heart disease, and disrupted blood flow at early embryonic stages is known to lead to congenital heart malformations. In spite of this, many of the mechanisms by which blood flow mechanics affect cardiovascular development remain unknown. This is due in part to the challenges involved in quantifying blood flow dynamics and the forces exerted by blood flow on developing cardiovascular tissues. Recent technologies, however, have allowed precise measurement of blood flow parameters and cardiovascular geometry even at early embryonic stages. Combined with computational fluid dynamics techniques, it is possible to quantify haemodynamic parameters and their changes over development, which is a crucial step in the quest for understanding the role of mechanical cues on heart and vascular formation. This study summarizes some fundamental aspects of modelling blood flow dynamics, with a focus on three-dimensional modelling techniques, and discusses relevant studies that are revealing the details of blood flow and their influence on cardiovascular development.This article is part of the Theo Murphy meeting issue 'Mechanics of development'.

Effect of blood lipid levels on cerebrovascular hemodynamic indices in a young and middle-aged population / 中华健康管理学杂志

Objective To explore the relationship between blood lipid levels and cerebrovascular hemodynamic indices (CVHI) in a young and middle?aged population, and to identify reference values for early warning of stroke. Method Between June 2015 and June 2016, a total of 6 252 young and middle?aged patients were assessed for cerebrovascular function in The Health Management Center of Affiliated Hospital of Guizhou Medical University. Patients were divided into abnormal and normal blood lipid groups. Differences in CVHI indicators and scores between the groups were determined, and factors influencing CVHI indices were compared using multivariate logistic regression analysis. Results Mean (Vmean), maximum (Vmax), and minimum blood flow velocity (Vmin) and cumulative scores for CVHI indices in the abnormal blood lipid group were significantly lower than in the normal blood lipid group (P<0.001). However, pulse wave velocity, characteristic impedance, peripheral vascular resistance, dynamic resistance, critical pressure, and differences between diastolic blood pressure and critical pressure were greater than those in the normal blood lipid group (P<0.001). Multivariate logistic regression analysis indicated that a high triglyceride level, overweight or obesity, high systolic blood pressure, high diastolic blood pressure, and age were risk factors for low CVHI scores, with odds ratios (95% confidence intervals) of 1.455 (1.195- 1.771), 2.271 (1.782-2.895), 5.967 (4.557-7.815), 4.251 (3.349-5.396), 2.560 (1.993-3.287), and 1.448 (1.189-1.763). Conclusion Abnormal blood lipid levels can lead to abnormal cerebrovascular function in young and middle?aged population; elevated triglyceride level was an independent risk factor for impaired cerebrovascular function.

Brachial artery blood flow dynamics during sinusoidal leg cycling exercise in humans.

To explore the control of the peripheral circulation of a nonworking upper limb during leg cycling exercise, blood flow (BF) dynamics in the brachial artery (BA) were determined using a sinusoidal work rate (WR) exercise. Ten healthy subjects performed upright leg cycling exercise at a constant WR for 30 min, followed by 16 min of sinusoidal WR consisting of 4-min periods of WR fluctuating between a minimum output of 20 W and a maximum output corresponding to ventilatory threshold (VT). Throughout the protocol, pulmonary gas exchange, heart rate (HR), mean arterial blood pressure (MAP), blood velocity (BV), and cross-sectional area of the BA, forearm skin BF (SBF), and sweating rate (SR) were measured. Each variable was fitted to a sinusoidal model with phase shift (θ) and amplitude (A). Nearly all variables closely fit a sinusoidal model. Variables relating to oxygen transport, such as VO2 and HR, followed the sinusoidal WR pattern with certain delays (θ: VO2; 51.4 ± 4.0°, HR; 41.8 ± 5.4°, mean ± SD). Conversely, BF response in the BA was approximately in antiphase (175.1 ± 28.9°) with a relatively large A, whereas the phase of forearm SBF was dissimilar (65.8 ± 35.9°). Thus, the change of BF through a conduit artery to the nonworking upper limb appears to be the reverse when WR fluctuates during sinusoidal leg exercise, and it appears unlikely that this could be ascribed exclusively to altering the downstream circulation to forearm skin.

The value of color doppler flow imaging in diagnosis of liver cirrhosis upper gastrointestinal bleeding about portal vein hemodynamic changes / 中国医学装备

Objective:To investigate the value of color doppler flow imaging (CDFI) in the diagnosis of liver cirrhosis upper gastrointestinal bleeding in portal vein hemodynamic changes. Methods: 96 cases of patients with liver cirrhosis were selected who were diagnosed in our hospital, according to the history whether patients had a gastrointestinal bleeding or not. They were divided into bleeding group(45 cases) and no bleeding group(51 cases). At the same time, we chose the hospital physical examination center of 42 cases of healthy volunteers as a control group, using color doppler flow imaging portal venous blood flow mechanics parameters, including diameter, average blood flow velocity and blood flow of portal vein(PV) and splenic vein(SV) and compare the data of the three groups.Results: Compared with control group, the patients with liver cirrhosis, the blood vessel diameter have increased whether bleeding or not. The average blood flow velocity is slower and PVF is larger, and the differences between them are statistically significant(t=3.579,t=3.670,t=4.750,t=3.951,t=6.116,t=5.371;P<0.05). Conclusion: The clinical application of color doppler flow imaging(CDFI) in patients with cirrhosis portal hemodynamic change is not only simple noninvasive, and there is important diagnostic value in the detecting parameters.

Effect of different doses of monocrotaline in combination with isopropylarterenol on the hemodynamic response, heart index and right heart hypertrophy index in rats / 中国比较医学杂志

Objective To study the effect of different doses of monocrotaline in combination with isopropylarterenol on the hemodynamic resonse, heart index and right heart hypertrophy index in rats.Methods Sixty-four healthy adult SD rats, male:female=1∶1, body weight 200-250 g, were randomly divided into blank control group (n=16) and three model groups (n=16 in each group).The high dose model group (n=16) received i.p.injection of monocrotaline 80 mg/kg once and epinephrine 10 mg/kg once daily for one week.The moderate dose group received i.p. injection of monocrotaline 55 mg/kg once and epinephrine 8 mg/kg once daily for one week.The low dose group received i. p.injection of monocrotaline 30 mg/kg once and epinephrine 3 mg/kg once daily for one week.The rats were fed for 6 weeks, and then pulmonary artery pressure and right ventricular pressure were tested and heart index and right ventricular hypertrophy index were determined.Results Compared with the control group, the mean pulmonary artery pressure and right ventricular systolic blood pressure in the low dose monocrotaline group were not significantly changed, but significantly changed in the moderate dose monocrotaline group ( P<0.05) .The heart index and right ventricular hypertrophy index in the low dose monocrotaline group were not significantly changed, but in the moderate dose monocrotaline group, the heart index was significantly reduced ( P<0.01 ) and the right ventricular hypertrophy index was significantly increased ( P<0.05 ) .Conclusions The use of a single injection of 55 mg/kg monocrotaline in combination with continuous injection of 8 mg/kg isopropylarterenol once daily for one week can ensure the survival rate of rats, and the successful formation of pulmonary artery hypertension, leading to heart weakness.

Quantitative assessment of hemodynamic changes during spinal dural arteriovenous fistula surgery.

We aimed to evaluate the efficacy of FLOW 800 (Carl Zeiss Meditec, Jena, Thuringia, Germany) with indocyanine green (ICG) videoangiography for the quantitative assessment of flow dynamics in spinal dural arteriovenous fistula (dAVF) surgeries. We prospectively enrolled nine patients with spinal dAVF diagnosed within the past year and performed FLOW 800 analyses using ICG videoangiography before and after surgical obliteration of the fistula. A color-coded map was semi-automatically generated by FLOW 800 and used for high-resolution visualization of the vasculature and instant interpretation of the dynamic flow changes. The FLOW 800-specific hemodynamic parameters were employed for real-time measurements of parenchymal perfusion alterations. Overall, 18 intraoperative FLOW 800 analyses using ICG videoangiography were performed in nine patients. The color-coded map aided the detection and complete obliteration of the fistulas in all patients and the results were verified by postoperative spinal digital subtraction angiography. The transit time parameter was significantly shorter in the preobliteration phase than in the postobliteration phase (p < 0.01), the rise time parameter exhibited the same pattern (p = 0.08) and maximum intensity and blood flow index were not significantly different between these phases. FLOW 800 with ICG videoangiography provided an intuitive and objective understanding of blood flow dynamics intraoperatively and enabled easy and confident identification and treatment of this pathology. The FLOW 800-specific hemodynamic analyses provided additional perfusion information that enabled real-time measurements of parenchymal perfusion alterations. FLOW 800 with ICG videoangiography is useful for intraoperative quantitative assessment of flow dynamics, facilitating safety and confidence in the treatment of spinal dAVF.

Effects of sevoflurane inhalation anesthesia on hemodynamic study in gy-necological laparoscopic surgery / 中国现代医生

Objective To study the gynecologic laparoscopic surgery sevoflurane inhalation anesthesia on hemodynamics. Methods All 87 cases of patients in our hospital from May 2012 to May 2014 in Department of Obstetrics and Gyne-cology with laparoscopic surgery, were randomly divided into the observation group and the control group, the obser-vation group treated with sevoflurane inhalation anesthesia for laparoscopic surgery (n=44), the control group using combined spinal and epidural anesthesia for laparoscopic surgery(n=43),hemodynamic changes during operation in two groups of patients were compared. Results The RR, SpO2, PETCO2 in the observation group were higher than those in the control group,the difference was statistically significant(P<0.05). T1 T0,the time of systolic blood pressure (SBP)and diastolic blood pressure (DBP)and heart rate did not change much after induction of anesthesia, and T2, T3 time point,the SBP,DBP,HR of control group were lower than those in the observation group, there was statistically sig-nificant difference between the two groups(P<0.05). Anesthesia was induced with T0,T1 time points,there was no sig-nificant difference in hormone levels in two groups of patients with NE,E,CORT,ATII in the blood(P>0.05);and T2 after induction of anesthesia, T3 time point, compared with the time point of T0, the difference was statistically signif icant(P<0.05). The observation group and the hormone levels were lower than the control group, the difference was statistically significant(P<0.05). Conclusion Laparoscopic surgery sevoflurane inhalation anesthesia, hemodynamics of patients with stable,safe and reliable means of anesthesia.