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To develop a tissue-engineered vascular graft, we used pericardial effusion-derived progenitor cells (PEPCs) collected from drained fluid after open-heart surgery in children with congenital heart diseases to repopulate a decellularized porcine pulmonary artery. The PEPCs were compared with human fibroblasts (HS68) and human umbilical vein endothelial cells (HUVECs) in cell growth and migration. They were cultured with the matrices via an inner approach (intima), lateral approach (media), and outer approach (adventitia). PEPCs grew and migrated better than the other two cells 14 days after seeding in the decellularized vessel. In immunofluorescence assays, PEPCs expressed CD90 and CD105 indicating a vascular differentiation. PEPCs grew in a decellularized porcine pulmonary artery matrix may have the potential for producing tissue-engineered vascular grafts. [ABSTRACT FROM AUTHOR]

Pleural effusion is a pathologic symptom in which there is accumulation of body fluids around the lungs. A chest radiograph is a rapid examination technique and does not require complex setup for making a preliminary diagnosis of lung and heart diseases. In radiographic visualization, the symptom patterns appear as light or dark areas in the lung cavity. Computer-aided diagnosis is an automatic manner that can rapidly highlight the object region by preanalyzing medical images. It can improve the problems of manual inspection and allow diagnosis in remote medical facilities. Based on the ratios of lung anatomy, the automatic screening manner based on pattern recognition can be viewed as pixel value detection in the bilateral lung cavities. In this study, a fractional-order convolution (FOC) process is used to enhance the original image for an accurate extrapolation of the desired object in an image. The specific object image feature can be improved, and an accurate quantification of the pleural effusion region can be obtained using the suitable ranges of fractional-order parameters. Based on the boundaries of homogeneous regions, the pixel ratios of the lung anatomy between normal and abnormal conditions can be computed. The pleural effusion sizes and volumes can be rapidly estimated through the number of pixel changes. The experimental results reveal that the feature maps are similar and stable on image enhancement and segmentation with two fractional-order enhancement masks, as fractional-order v = 0.05 to 0.20 for mask 1# and v = 0.80 to 0.95 for mask 2#, respectively. The results also demonstrate the feasibility of the study on combining two-dimensional image FOC-process and bounding box pixel analysis to estimate the moderate and large effusion sizes from 500–2,000 mL. [ABSTRACT FROM AUTHOR]

Pulmonary valve diseases include the different degrees of aortic stenosis or congenital defects in children or adults. Valve repair or replacement surgery is commonly performed to relieve valvular dysfunction and improve the significant flow regurgitation in the aortic valve and the pulmonary valve. However, commercial valve stents and valved conduits are sometimes not available for children or patients with special conditions. The handmade trileaflet valve design has been used with different range of diameters for patch-valved conduit reconstruction. Thus, we propose a multiple regression model, as a generalized regression neural network (GRNN), to determine the optimal trileaflet parameters, including the width, length, and upper lower curved structure. Through computed tomography pulmonary angiography, while the diameter of the main pulmonary artery is determined, a leaflet template can be rapidly sketched and made. Using an experimental pulmonary circulation loop system, the efficacy of the valved conduit can be validated using the regurgitation fraction method. In contrast to commercial valve stents, experimental results indicate that the handmade trileaflet valve can also improve severe pulmonary regurgitations. [ABSTRACT FROM AUTHOR]

We aimed to compare the hypothesized local anesthetic action of amantadine (1-adamantanamine) with that of the known local anesthetic mepivacaine. Motor, proprioceptive, and nociceptive functions were evaluated in rats after intrathecal administration. Amantadine elicited spinal anesthesia in a dose-related fashion and produced a better sensory-selective action over motor blockade ( P < 0.01). On the 50% effective dose ( ED50) basis, the rank of potency on spinal motor, proprioceptive, and nociceptive block was mepivacaine > amantadine ( P < 0.01 for the differences). Amantadine (63.5 μmol/kg) and mepivacaine (7.1 μmol/kg) produced complete spinal block of motor function, proprioception, and nociception. On an equipotent basis ( ED25, ED50, and ED75), the duration of amantadine was longer ( P < 0.01) than that of mepivacaine on spinal motor, proprioceptive, and nociceptive block. Our preclinical data demonstrated that amantadine was less potent than mepivacaine at producing spinal anesthesia. The spinal block duration produced by amantadine was greater than that produced by mepivacaine. Both amantadine and mepivacaine produced a markedly nociceptive-specific blockade. [ABSTRACT FROM AUTHOR]

Veno‐venoarterial extracorporeal membrane oxygenation is an upgraded configuration that provides well‐oxygenated blood to the systemic and pulmonary circulations. Sufficient sized cannulas, gas exchange capability, and other equipment should be selected to fulfil the desired extracorporeal supporting flow for temporary life support. Therefore, an accurate prediction model is used to screen the optimal combinations of cannula sizes and determine adequate extracorporeal flow for gas exchange. Prediction models use a substitution‐rate matrix to choose optimal combinations under hemodynamic stability, and a generalised regression neural network to estimate the desired pump speed required to maintain sufficient flow. Experimental studies are used to validate the proposed model and suggest further modifications in the base/reference for the intensive care unit. [ABSTRACT FROM AUTHOR]

For end-stage renal disease patients undergoing hemodialysis, thrombosis caused by stenosis hinders the long-term use of vascular access. However, traditional spectral bruit analysis techniques for detecting the severity of vascular access stenosis are not robust. Accordingly, the present study proposes an automated method for mimicking a trained practitioner in performing the auscultation process. In the proposed approach, the bruit obtained using a standard phonoangiographic method is transformed into the time-frequency domain, and two spectro-temporal features, namely the auditory spectrum flux and the auditory spectral centroid, are then extracted. The distributions of the two features are analyzed using a multivariate Gaussian distribution (MGD) model. Finally, the distribution parameters of the MGD model are used to detect the presence (or otherwise) of vascular access stenosis. The validity of the proposed approach is investigated using the phonoangiography signals obtained from 16 hemodialysis patients with straight arteriovenous grafts over the upper arm region. The results show that the MGD covariance matrix coefficient of the auditory spectral centroid feature yields an accuracy of 83.87 % in detecting significant vascular access stenosis. Thus, the proposed method has significant potential for the applications of vascular access stenosis detection. [ABSTRACT FROM AUTHOR]

The aorta, including the thoracic and abdominal aortas, distributes blood from the heart to the upper and lower circulatory systems. Abdominal aortic sclerosis can cause abdominal aortic aneurysm. When the diameter of the aorta increases by more than 1.5 times its normal size (e.g., ≥4−5 cm, mean diameter in an adult is 2−3 cm), the risk of aneurysm rupture gradually increases. Aneurysm rupture and its associated bleeding have high mortality rates. Hence, the prediction of large diameter aortic aneurysms is an important issue with great clinical implications. In computed tomography angiography (CTA) imaging examination, an assistive tool for automatic image segmentation must be developed to help cardiologists and radiologists evaluate the risk of rupture progression and make appropriate treatment decisions. In this study, two‐dimensional (2D) spatial convolution operations (corner detection) and a multilayer machine vision classifier enabled the automatic segmentation of the luminal region, vascular intima, and calcified plaques in the abdominal aorta. The 2D spatial convolution operations can efficiently increase focus, remove unwanted noise in the convolutional layer, and segment calcified plaques and the vessel border by using a general regression neural network (GRNN)‐based classifier. The classifier's outputs can also be visualized in color presentation (red, green, and blue color series) to identify vessel borders and calcified plaques. Luminal change rate (LCR), calcified plaque rate (CPR), and ellipse ratio (ER) can be defined as criteria for evaluating changes in the luminal region and locating calcified plaques, which can be used to identify the locations of cross‐sectional shape changes and calcified plaques. Based on the collected CTA images from the clinical case studies, the proposed multilayer classifier has promising results for the intended medical purpose. With the LCR index, the correlation coefficients (R2) for manual image segmentation and automatic image segmentation is >0.90 in positive correlation for vessel borders segmentation. The proposed method is an adaptive learning scheme with potential clinical applications in automatic CTA image segmentation for further abdominal aortic aneurysm (AAA) risk evaluation. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Biogenic microvesicles (MVs) play a pivotal role in intercellular signal communication, thus initiating critical biological responses such as the proliferation of cancer cells, gene and protein transport, and chemo-drug resistance. In addition, they have been recognized as having great potential in drug delivery applications. However, the productivity of biologically produced MVs is not sufficient for clinical applications. In this study, synthetic poly(lactic-co-glycolic acid) (PLGA) MVs were prepared via a double emulsion method. The PLGA MVs had a biogenic MV-mimic vesicular structure with a hydrophilic core/surface and hydrophobic interior of the shell, showing great potential for drug delivery. We successfully embedded hydrophobic iron carbonyl (IC), a carbon monoxide (CO) donor, in the PLGA shell region, enabling the delivery of IC in an aqueous solution. Because of the intrinsic properties of PLGA, it was susceptible to temperature, and the MVs could easily collapse in a warm environment, leading to the decomposition of IC into CO. The in vitro result indicated that the cell viability of A549 lung carcinoma cells significantly decreased to 14% after treatment with IC-loaded PLGA MVs for 24 h, suggesting that these synthetic PLGA MVs constitute an excellent drug delivery platform. [ABSTRACT FROM AUTHOR]

The conductance catheter technique was developed in the 1980s to measure instantaneous ventricular conductance. After converting measured conductance to volume signals by use of the classic Baan conductance-to-volume equation, real-time pressure–volume (PV) relations can be obtained. A nonlinear conductance-to-volume conversion equation was proposed by Wei in 2005 to improve the accuracy of the conductance catheter system. This study tested the in vivo applicability of the nonlinear conversion equation, particularly focusing on the effect of deviation in catheter position. By altering catheter position, PV loops obtained by using the classic Baan's equation and the nonlinear equation were compared. The comparison results show that the nonlinear equation indeed compensates for the errors introduced by catheter position deviation, and gives more consistent and reliable PV relations. Moreover, the effect of variations in blood resistivity was analyzed. To obtain consistent and reliable PV relations, the nonlinear equation is suggested for use, and changes in blood resistivity should be carefully monitored. [ABSTRACT FROM AUTHOR]

Introduction. Most of the glyphosate-surfactant herbicides (GlySH) are formulated commercial products containing isopropylamine (IPA) salt of glyphosate (IPAG), variable amount of a surfactant, and water. Although glyphosate is only slightly toxic to rats, ingestion of GlySH may lead to severe effects, including death, in humans. We conducted a study to evaluate the cardiovascular effects of the components of GlySH. Methods. We used five groups of male piglets, each receiving infusion of normal saline (control), glyphosate in NaOH base, IPA, IPAG, and polyoxyethyleneamine (POEA), respectively. We chose concentrations that are similar to those in the commonly used GlySH (41% of IPAG and 15% surfactant). Results. We found that IPAG reduced the mean arterial blood pressure (MABP) and left-ventricular stroke work index (LVSWI) during the infusion, but both recovered gradually. It also decreased the cardiac index but increased the pulmonary capillary wedge pressure, central venous pressure (CVP), and mean pulmonary arterial pressure (MPAP). POEA infusion reduced the cardiac index and LVSWI, but not the MABP. It also increased the pulmonary capillary wedge pressure, CVP, MPAP, and pulmonary vascular resistance index. IPA increased the MABP, which was higher than those in the control, IPAG, and POEA groups. Glyphosate in NaOH base infusion did not affect the hemodynamics but slightly reduced the blood pH and base excess (BE) values. POEA and IPAG also resulted in metabolic acidosis, with lactate formation and decreased BE values. Conclusion. We conclude that both POEA and IPAG infusion affected hemodynamics and resulted in death in piglets, whereas glyphosate (NaOH base) had no similar effects. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the current study was to evaluate the effect of recipient age on the regenerative response to implantation with young skeletal myoblasts (SKMCs) after a coronary artery ligation. Background: In contrast with previous findings in animals, the initial clinical trials of cell transplantation after a myocardial infarction have reported only limited improvements in ventricular function. The restricted regenerative capacity of cells isolated from older patients is certainly a factor; however, the present study investigated the impact of another potentially significant factor: recipient age. Methods: We compared the myogeneic capacities of SKMCs isolated from young rats (3 months old) and older rats (24 months old). Highly myogenic SKMCs derived from young rats (or culture media, in control rats) were then transplanted into the infarcted myocardium of young and older recipients at 1 week after coronary ligation. Results: In vitro, proliferation and myotube formation were significantly greater in SKMCs derived from young rats than from older rats. In vivo, young and older recipients of SKMCs exhibited increases in cell density, vascular density, and collagen preservation relative to age-matched control animals. However, cell therapy produced significantly greater functional improvements in young recipients than in older, along with relative increases in stem cell factor, cell density, cell survival, and angiogenesis. Conclusions: Functional improvement after the post–myocardial infarction implantation of young SKMCs was limited in older recipients, likely due to reductions in their cardiac and systemic responses to cell transplantation. [Copyright &y& Elsevier]

Abstract: Background:: Anticoagulation is an essential part ofthe management of numerous cardiovascular conditions. Although warfarin sodium has been in clinical use for >40 years, only 1 proprietary warfarin preparation was in use for long-term anticoagulation in Taiwan until 2001, when the Taiwan Food and Drug Administration approved a new generic formulation. Objective:: This study evaluated the efficacy and tolerability of switching from an established dose of the branded warfarin sodium product (in mg/wk) to the same dose of the generic product. Methods:: This was a randomized, observer-blinded,crossover study in Taiwanese patients who received a mechanical heart valve to replace an original valve or a previously implanted mechanical valve from March 2003 to August 2004 and had received branded warfarm therapy for ≥2 months postoperatively, with a mean baseline international normalized ratio (INR) in the range from 1.7 to 3.0 in the 8- to 12-week run-in period. Patients were randomized to 1 of 2 treatment sequences, each involving three 28-day periods: the generic product for 1 period followed by the branded product for 2 periods, or the branded product for 1 period followed by the generic product for 2 periods. Prothrombin time and INR were measured, and anticoagulant activity was compared. At each visit, treatment-emergent adverse events were recorded and evaluated by the blinded observer, an internal medicine physician who was not involved in patients'' care. Results:: Thirty-five patients were enrolled (25 men, 10 women; mean age, 52.4 years [range, 34.5–74.4 years]). All but 2 of the patients had received a replacement for a natural heart valve. Thirty-four patients (16 who received the generic product initially, 18 who received the branded product initially) completed the study without a dose change and were ≥75% compliant with therapy. There was no difference in pooled mean (SE) INR between the 2 products (2.28 [0.06] and 2.27 [0.06], respectively). The 90% CI for the difference was 96.4 to 104.9, well within the range for bioequivalence (80–120). There were no differences in the adverse-event profiles of the 2 formulations. Conclusions:: No therapeutic inequivalence wasdemonstrated in this small, single-blind study, suggesting that the generic and branded warfarin products studied were equally effective in maintaining anticoagulation in patients with mechanical prosthetic heart valves. The 2 products had similar safety profiles. [Copyright &y& Elsevier]

Background: The roots of Codonopsis pilosula (Franch.) Nannf. have been used in traditional Chinese medicine for treating cardiovascular disease. In the current study, we aimed to discover herbal extracts from C. pilosula that are capable of improving cardiac function of infarcted hearts to develop a potential therapeutic approach. Methods: A mouse embryonic stem (ES) cell-based model with an enhanced green fluorescent protein (eGFP) reporter driven by a cardiomyocyte-specific promoter, the α-myosin heavy chain, was constructed to evaluate the cardiogenic activity of herbal extracts. Then, herbal extracts from C. pilosula with cardiogenic activity based on an increase in eGFP expression during ES cell differentiation were further tested in a rat myocardial infarction model with left anterior descending artery (LAD) ligation. Cardiac function assessments were performed using echocardiography, 1, 3, and 6 weeks post LAD ligation. Results: The herbal extract 417W from C. pilosula was capable of enhancing cardiogenic differentiation in mouse ES cells in vitro. Echocardiography results in the LAD-ligated rat model revealed significant improvements in the infarcted hearts at least 6 weeks after 417W treatment that were determined based on left ventricle fractional shortening (FS), fractional area contraction (FAC), and ejection fraction (EF). Conclusions: The herbal extract 417W can enhance the cardiogenic differentiation of ES cells and improve the cardiac function of infarcted hearts. [ABSTRACT FROM AUTHOR]

Background: We sought to investigate the differential impact of EVAR (endovascular aneurysm repair) vis-à-vis OSR (open surgical repair) on ruptured AAA (abdominal aortic aneurysm) mortality by sex and geographically. Methods: We performed a retrospective study of administrative data on EVAR from state statistical agencies, vascular registries, and academic publications, as well as ruptured AAA mortality rates from the World Health Organization for 14 14 states across Australasia, East Asia, Europe, and North America. Results: Between 2011–2016, the proportion of treatment of ruptured AAAs by EVAR increased from 26.1 to 43.8 percent among females, and from 25.7 to 41.2 percent among males, and age-adjusted ruptured AAA mortality rates fell from 12.62 to 9.50 per million among females, and from 34.14 to 26.54 per million among males. The association of EVAR with reduced mortality was more than three times larger (2.2 vis-à-vis 0.6 percent of prevalence per 10 percentage point increase in EVAR) among females than males. The association of EVAR with reduced mortality was substantially larger (1.7 vis-à-vis 1.1 percent of prevalence per 10 percentage point increase in EVAR) among East Asian states than European+ states. Conclusions: The increasing adoption of EVAR coincided with a decrease in ruptured AAA mortality. The relationship between EVAR and mortality was more pronounced among females than males, and in East Asian than European+ states. Sex and ethnic heterogeneity should be further investigated. [ABSTRACT FROM AUTHOR]

Human cardiac progenitor cells isolated from the same host may have advantages over other sources of stem cells. The aim of this study is to establish a new source of human progenitor cells collected from a waste product, pericardiac effusion fluid, after open-heart surgery in children with congenital heart diseases. The fluid was collected every 24 h for 2 days after surgery in 37 children. Mononuclear cells were isolated and expanded in vitro. These pericardial effusion-derived progenitor cells (PEPCs) exhibiting cardiogenic lineage markers, were highly proliferative and enhanced angiogenesis in vitro. Three weeks after stem cell transplantation into the ischemic heart in mice, cardiac ejection fraction was improved significantly without detectable progenitor cells. Gene expression profiles of the repaired hearts revealed activation of several known repair mechanisms including paracrine effects, cell migration, and angiogenesis. These progenitor cells may have the potential for heart regeneration. [ABSTRACT FROM AUTHOR]

Human cardiac progenitor cells isolated from the same host may have advantages over other sources of stem cells. The aim of this study is to establish a new source of human progenitor cells collected from a waste product, pericardiac effusion fluid, after open-heart surgery in children with congenital heart diseases. The fluid was collected every 24 h for 2 days after surgery in 37 children. Mononuclear cells were isolated and expanded in vitro. These pericardial effusion-derived progenitor cells (PEPCs) exhibiting cardiogenic lineage markers, were highly proliferative and enhanced angiogenesis in vitro. Three weeks after stem cell transplantation into the ischemic heart in mice, cardiac ejection fraction was improved significantly without detectable progenitor cells. Gene expression profiles of the repaired hearts revealed activation of several known repair mechanisms including paracrine effects, cell migration, and angiogenesis. These progenitor cells may have the potential for heart regeneration. [ABSTRACT FROM AUTHOR]

Peripheral arterial disease (PAD) is highly prevalent in haemodialysis (HD) patients with type 2 diabetes. Atherosclerosis may occur in both lower and upper peripheral arteries, causing progressive dialysis access stenosis in HD patients. To assess the risk of PAD, non‐invasive bilateral photoplethysmography (PPG) can be used to obtain continuous variations in blood flow volume in in vivo examinations. The authors propose an astable multivibrator to model the peripheral circulation system and to produce PPG oscillation with time constants, duty ratio (rising time), and amplitude ratio of systolic and diastolic pressures. Then, the bilateral differences in the time constant and duty ratio are used to separate the normal condition from PAD. The machine learning decision‐making process utilises a screening method to automatically detect subjects with and without the risk of PAD. The radial‐based function is employed to parameterise the similarity and dissimilarity levels using probability values. Colour relation analysis incorporates the probability values into the perceptual colour relationships for PAD screening. The experimental results indicate that in comparison with bilateral timing parameters, degree of stenosis, and resistive index, the proposed screening method is efficient in preventing complications of PAD and is easily implemented in an embedded system. [ABSTRACT FROM AUTHOR]

BACKGROUND: The increasing prevalence of end-stage renal disease (ESRD) imposes a substantial economic burden on public health-care systems. Hemodialysis (HD) is a pivotal treatment modality for patients with ESRD. However, prolonged use of HD vessels may result in stenosis, thrombosis, and occlusion due to repeated daily punctures. Thus, early detection and prevention of the dysfunction of dialysis routes are crucial. OBJECTIVE: In this study, we designed a wearable device for the early and accurate detection of arteriovenous access (AVA) stenosis in HD patients. METHODS: A personalized three-dimensional (3D) printed wearable device was designed by combining the phonoangiography (PAG) and photoplethysmography (PPG) techniques. The capability of this device to monitor AVA dysfunction before and after percutaneous transluminal angioplasty (PTA) was evaluated. RESULTS: After PTA, the amplitudes of both PAG and PPG signals increased in patients with arteriovenous fistulas and those with arteriovenous grafts; this might be due to increased blood flow. CONCLUSION: Our designed multi-sensor wearable medical device using PAG, PPG, and 3D printing appears suitable for early and accurate detection of AVA stenosis in HD patients. [ABSTRACT FROM AUTHOR]

Maintaining adequate dry weight and fluid volume balance is an important issue for dialysis patients. Malnutrition and sodium intake are the primary factors that cause fluid volume imbalance and changes in body weights. Inadequate dry weight control results in higher levels of blood pressures and is related to various complications, such as volume overload, hypertension, congestive symptoms, and cardiovascular diseases. Moreover, inadequate fluid removal provokes hypotension during dialysis treatment. Thus, we propose an early warning tool based on fuzzy color reason analysis in predialysis healthcare for hypervolemia screening. The anthropometric method is a rapid, non-invasive, and simple technique for estimating the total body water. In this study, Watson standard formula is employed to estimate cross-sectional standard of total body water with the patient characteristics, including gender, age, height, and weight. In contrast to the experienced anthropometric formulas, Watson formula has less than 2% of margin errors and provides a criterion as a reference manner to estimate the total body water in patient’s normal dry weight. In addition, inadequate dry weight and total body water controls will lead to higher blood pressures. The systolic blood pressure is also an indicator to evaluate pre-hypertension of 120–139 mmHg and hypertension of greater than or equal to 140 mmHg. Therefore, the levels of two indicators, total body water and systolic blood pressure, are parameterized with fuzzy membership grades to describe the normal and the specific ranges of undervolemia and hypervolemia. A color reason analysis utilizes a hue–saturation–value color model to design a color perceptual manner for separating normal condition from hypervolemia or undervolemia. Normalized hue angle and saturation value provide a promising visual representation with color codes to realize the patients’ diagnosis. Dialysis patients with hypertension demonstrated that the proposed model can be used in clinical applications. In addition, a healthcare chair is carried out to measure blood pressure and weight in predialysis. The proposed assistant tool integrates an electronic pressure monitor and an electronic weight monitor, and fuzzy color reason analysis is also intended to be established in an intelligent vehicle via a WiFi wireless local area network for cloud computing. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 16-year-old boy who was admitted to an emergency department because of chest pain with back radiation. Findings of chest X-ray and emergency chest computed tomography revealed whiteout of the left thorax and a ruptured aortic arch aneurysm, respectively. The patient underwent emergency surgery for the reconstruction of hybrid aortic arch, but died after prolonged shock.

Patent ductus arteriosus (PDA) is a common cardiovascular complication that complicates clinical care in the intensive care of premature infants. Prenatal and postnatal infections and the inflammation process can contribute to PDA, and intrauterine inflammation is a known risk factor of PDA. A variety of inflammatory biomarkers have been reported to be associated with PDA. Chorioamnionitis induces the fetal inflammatory process via several cytokines that have been reported to be associated with the presence of PDA and may have a role in the vascular remodeling process or vessel dilation of the ductus. On the other hand, anti-inflammatory agents, such as antenatal steroids, decrease PDA incidence and severity in patients born to those with chorioamnionitis. Proinflammatory cytokines, which are expressed more significantly in preterm neonates and chorioamnionitis, are associated with the presence of PDA. In this review, we focus on the pathogenesis of PDA in preterm infants and the role of biomarkers associated with the perinatal inflammatory process. [ABSTRACT FROM AUTHOR]

In clinical examinations, narrowed vessel accesses will produce unsteady flow and cause changes in blood flow volume. These phenomena result in pressure, velocity and flow resistance increases and induce stress on vessel walls. The vessel wall vibrates and squeezes the low axial blood flow, a lumped resistor (R) representing resistance to blood flow. The compliance is a pressure against blood volume relationship, a lumped capacitor (C) representing the compliance capacity of the blood vessel. Vibration phenomena results on the elastic vessel wall because of transverse vibration pressure. Turbulent and instability flow will induce simple harmonic motions, and the rise time, amplitude and pulse duration of transverse vibrations are determined by the flow resistances and vessel compliances. Hence, an astable multivibrator as detection model employs time constant, τ = (R × C), to evaluate the flow instability and the dysfunction risk in in‐vitro arteriovenous grafts (AVGs). Experimental results show the time constants have linear regression with a positive correlation as the degree of stenosis increases. Positive pole values, s = (−1/τ), are used to validate that the AVG be unstable because the force responses will continuously grow with time because of vibration increases. For comparison with the computerised analysis and auscultation method, in‐vivo examinations of the proposed equivalent model can be further carried out for screening of AVG dysfunction. [ABSTRACT FROM AUTHOR]

Prospective electrocardiography (ECG)-gated cardiac computed tomography angiography (CTA) is widely used for pediatric patients with congenital heart disease (CHD) due to the lower radiation dose compared with the ECG-gated technique. However, functional parameters acquired using ECG-gated cardiac CT to predict pulmonary hypertension (PH) in children with CHD have not yet been reported. This study aimed to investigate the potential of diastolic and systolic right ventricular diameters (RVD) on prospective ECG-gated cardiac CTA to predict PH in children with CHD. A total of 44 children with CHD were divided into two groups: CHD with PH (n = 22) and CHD without PH (n = 22). The association between ECG-gated CTA parameters and PH was evaluated by logistic regression. The receiver operating characteristic curve (ROC) was used to find the best cut-off point for the parameters measured by Youden's index. Patients with higher RVD-BSA [aOR (95% CI) diastolic: 2.76 (1.23–6.23); systolic: 6.15 (1.72–22.06)] had higher risk of PH after adjusting for age and patent ductus arteriosus. The area under the curve (AUC) of D-RVD-BSA was 0.907 and the AUC of S-RVD-BSA was 0.917. Logistic regression showed that patients with D-RVD-BSA over 6.86 or S-RVD-BSA over 5.87 had significantly higher risk of PH after adjustments (aOR = 23.52, 95% CI = 2.89–191.03; aOR = 31.14, 95% CI = 2.75–352.85). In conclusion, in children with CHD, measurements of diastolic or systolic BSA-modified RVDs on prospective ECG-gated CTA are non-invasive markers of PH. BSA-modified D-RVD of 6.86 or BSA-modified S-RVD of 5.87 may be used to identify PH in children with CHD. • In children with PH, an association is found between ECG-CTA-gated image parameters and PH. • Diastolic-RVD & systolic-RVD are associated with pulmonary arterial systolic pressure. • Patients with D-RVD-BSA over 6.86 had significantly higher risk of PH. • Patients with S-RVD-BSA over 5.87 had significantly higher risk of PH. • The AUCs of diastolic-RVD and systolic-RVD were 0.907 and 0.917, respectively. [ABSTRACT FROM AUTHOR]

Background Coronary artery bypass grafting (CABG) is frequently performed in patients with end-stage renal disease (ESRD) together with severe coronary artery disease, after which, patients with ESRD have higher surgical risk and poorer long-term outcomes. We report our experience in patients with ESRD who survived in CABG and identify predictors of long-term outcomes. Methods We retrospectively investigated 93 consecutive patients with ESRD who survived to discharge after isolated CABG between January 2005 and December 2016 at our institution. Long-term outcomes, including all-cause mortality after discharge, readmission due to major adverse cardiac events, and reintervention, were evaluated. Predictors affecting long-term outcomes were also analyzed. Results The rates of freedom from all-cause mortality after discharge in 1, 3, 5, and 10 years were 92.1, 81.3, 71.9, and 34.9%, respectively. The rates of freedom from readmission due to major adverse cardiac events in 1, 3, 5, and 10 years were 90.7, 79.1, 69.9, and 55.6%, respectively. The rates of freedom from reintervention in 1, 3, 5, and 10 years were 95.3, 86.5, 79.0, and 66.6%, respectively. Postoperative β-blocker and statin use significantly improved overall long-term survival (β-blocker, p = 0.013; statin, p = 0.009). After case–control matching, patients who received statins showed better long-term survival than those without statins. The comparison of long-term survival between patients with and without β-blockers showed no significant difference after matching. Conclusions After CABG, dialysis patients who survived to discharge had acceptable long-term overall survival. Post-CABG statin use in dialysis patients is a predictor of better long-term survival. [ABSTRACT FROM AUTHOR]

An arteriovenous graft (AVG) has a higher patency rate in stenosis progression at the venous anastomosis site, which causes coexisting inflow and outflow stenoses. This leads to increases in blood pressure, flow velocity, and flow resistance, resulting in hemodialysis (HD) vascular access dysfunction from early clots and thrombosis to the progression of coexisting stenoses. To prevent vascular access complications such as inflow or outflow stenoses, this study proposes a novel examination method in an experimental AVG system using a substitution-rate based screening model. In our practical measurements, we found that inflow and outflow channeled through a narrowed access indicated both pressure and resistance differences as the degree of stenosis (DOS) gradually increased. A substitution-rate matrix was conducted to replace bilateral pressure variations, while a transition probability matrix was calculated. Differences in transition probabilities were then used to distinguish between normal conditions and flow instabilities using the distance estimation method. The joint probability decayed from < 0.81 to 0.00 could be specified to identify the progression in stenosis levels from a DOS% = 50.0-95.0%. Average joint probabilities were found to be inversely related with the DOS using a non-linear regression (R>2 0.90). Hence, the joint probability could be specified as a critical threshold, < 0.81, to identify the severity stenosis level, DOS% ⩾ 70%, in the assessment of coexisting inflow and outflow stenoses. Experimental results suggest that the proposed model is superior to hemodynamic analysis and traditional intelligent method, and can be used for dysfunction screening during HD treatment. [ABSTRACT FROM AUTHOR]

Narrowed vessel accesses produce blood flow changes, and induce flow instability and vessel wall vibration, resulting in blood pressure, flow velocity, and flow resistance increases. The vessel wall vibrates and propagates the low axial blood flow, as representing the resistance (R) to blood flow. The compliance is a blood pressure-blood volume relation, representing the systole and diastole capacity of the blood vessel. These dynamic behaviors increase blood flow resistances and reduce blood vessel compliances. Vibration phenomena result on the elastic vessel walls and induce simple harmonic motion due to transverse vibration pressure (TVP). The rise time, amplitude, and pulse duration of transverse waves are determined by the flow resistances (R) and vessel compliances (C). Thus, a stenotic arteriovenous access has high resistance and low compliance, which can be expressed an astable multivibrator as an equivalent model consisting of a lumped resistor (R) and a lumped capacitor (C). TVP's oscillation frequency, rise time, and amplitude are determined by the flow resistances and vessel compliances. Hence, an astable multivibrator is used to model TVP parameters to estimate negative time constants, τ=(R× C), which are used to evaluate the flow instability and the dysfunction risk in in-vitro arteriovenous grafts (AVGs). Experimental results show the average negative time constants have the positive correlation as the degree of stenosis (DOS) increases (R2 = 0.8944), and their variations with the flow resistance and vessel compliance are also validated. Positive pole values, s=(-1/τ), are used to show that the force responses of the vessel walls grow in a finite time, 0.5415 ± 7.60 × 10-3 sec, and the equivalent model would be also unstable as DOS increases (R2 = 0.8802). By comparison with hemodynamic analysis, the finding of proposed model can be further carried out for screening AVG dysfunction risk during hemodialysis treatment. [ABSTRACT FROM AUTHOR]

Vascular access dysfunction commonly occurs in hemodialysis patients. Regularly monitoring and evaluating the vascular access condition is an important issue for these diseased patients. The objective of this study was to identify acoustic parameters and hemodynamics that related to changes in the stenosis of vascular access. In-vitro experimental circulation system offered pulsatile and physiological condition to simulate the arteriovenouse access in hemodialysis patient. We created the environments of various degrees of stenosis (DOS) inside the arteriovenouse access to simulate the stenotic conditions in patients. And we also used the computational fluid dynamics (CFD) to simulate the pressure distribution, primary axial velocity distribution, and secondary flow distribution in the same various DOS and boundary condition. There are two findings, one is recorded the bruit which caused by the fluctuation of fluid in different severe stenosis, the other is described the correlation between bruit and hemodynamic parameters. Experimental results show the time constants have linear regression with a positive correlation as the degree of stenosis (DOS) increases. Finally, in contrast to CFD computerized analysis and acoustic methods, the proposed parameter provides a feasibility index for evaluating the risk of AVG dysfunction in on-line/real time analysis. [ABSTRACT FROM AUTHOR]

To detect the early developmental stages of arteriovenous access (AVA) stenosis in hemodialysis patients, this study explored a stenosis detector based on the Burg method and the fractional-order chaos system (FOCS). The bruit developed by the blood flowing through AVA can be a viable noninvasive strategy for monitoring AVA functions. We used the Burg method of the autoregressive model to estimate the frequency spectra of phonographic signals recorded by an electronic stethoscope in patients' AVAs and to identify the spectral peaks in the region of 25-800 Hz. The frequency spectra differed significantly between normal and stenosis statuses in AVA. We found that the frequency and amplitude in power spectra analysis varied in accordance with the severity of AVA stenosis. However, the correlation of these parameters for classifying the degree of stenosis is limited when only using the Burg method. Therefore, we used an FOCS to monitor the differing frequency spectra between the normal condition and AVA stenosis. The variances of these two conditions were dynamic errors that were the coupling variables that tracked the responses between the master system and the slave system. A total of 42 patients who had received percutaneous transluminal angioplasty (PTA) for their failing AVAs was recruited for this study. In this study, the dynamic error, Index Ψ, was used to calculate the frequency spectrum redistribution in patients undergoing PTA. In addition, ΔImp was the index used to evaluate improvements in the luminal diameter between pre- and post-PTA. Therefore, we used linear regression to model the relationship between ΔImp and Index Ψ. The findings indicate that the proposed method has enhanced efficiency, especially in the venous anastomosis (V-site). The FOCS is a novel and simple algorithm for analyzing the residual AVA stenosis of PTA treatment. [ABSTRACT FROM AUTHOR]

Background: Computed tomography (CT) is the modality of choice in the diagnosis of mycotic aneurysms. The present study aimed to classify the CT findings of mycotic aneurysms, and to assess their predictive value based on the correlation of a CT-based grading system with prognostic factors and outcomes. Methods: Over the past 21 years, 40 consecutive patients underwent open surgery for mycotic aneurysms of the abdominal aorta and iliac arteries in our hospital. The CT appearances of mycotic aneurysms were categorized into four grades: grade 1, periarterial changes without destruction of the arterial wall; grade 2, presence of saccular outpouching; grade 3, extensive retroperitoneal infection; and grade 4, massive perianeurysmal hemorrhage. Clinical data were recorded for analysis. Results: The surgical mortality and overall aneurysm-related mortality rates were 17.5 and 25 %, respectively. The poor prognostic predictors were shock, rupture, and concomitant gastrointestinal procedures. The increasing proportions of shock and rupture status corresponded to mycotic aneurysms of higher grades in the CT-based grading. In addition, one patient in grades 1 and 2, versus five in grades 3 and 4 ( P = 0.02), required concomitant gastrointestinal procedures. The CT-based grading exhibited a strong association with surgical mortality (Cramer's V coefficient = 0.65; P = 0.002) and a relatively strong association with overall aneurysm-related mortality (Cramer's V coefficient = 0.53; P = 0.01). Conclusions: For patients surgically treated for abdominal mycotic aneurysms, the CT-based grading is correlated with clinical severity, surgical complexity, and outcomes, and thus it may serve as a simple scale for risk classification. [ABSTRACT FROM AUTHOR]

Abstract: Though promazine and chlorpromazine elicited cutaneous anesthesia, no study of spinal anesthesia with chlorpromazine and promazine has been reported. This study was to examine whether chlorpromazine and promazine produce spinal anesthesia. Using a rat model via intrathecal injection, we tested spinal blockades of motor function and nociception by promazine, chlorpromazine or bupivacaine, and so were dose–response studies and durations. We demonstrated that chlorpromazine and promazine elicited dose-dependent spinal blockades in motor function and nociception. On the 50% effective dose (ED50) basis, the rank of potency of these drugs was bupivacaine>promazine>chlorpromazine (P <0.05 for the differences). On an equipotent basis (25% effective dose [ED25], ED50, and ED75), the block duration caused by chlorpromazine or promazine was longer than that caused by the long-lasting local anesthetic bupivacaine (P <0.01 for the differences). Chlorpromazine and promazine, as well as bupivacaine, showed longer duration of sensory block than that of motor block. Our data reported that intrathecal promazine and chlorpromazine with a more sensory-selective action over motor blockade had less potent and longer-lasting spinal blockades when compared with bupivacaine. [Copyright &y& Elsevier]

We present a case of 58-year-old woman with underlying diabetes mellitus, hepatitis C virus-related liver cirrhosis, and total hysterectomy for uterine myoma 11 moths ago, who was diagnosed ruptured aortic arch mycotic pseudoaneurysm after a certain period of survey for her unknown fever cause. After emergent surgery with prosthetic graft interposition, all her blood cultures and tissue cultures revealed pathogen with Bacteroides fragilis. Although mycotic aneurysms have been well described in literatures, an aneurysm infected solely with Bacteroides fragilis is unusual, with only eight similar cases in the literature. Here we reported the only female case with her specific clinical and management course and summarized all reported cases of mycotic aneurysm caused by Bacteroides fragilis to clarify their conditions and treatments, alert the difficulty in diagnosis, and importance of highly suspicious. [ABSTRACT FROM AUTHOR]