Changes In Diameter Research Articles

Retinal and Macular Changes in Pregnant Women of Advanced Maternal Age: A Retrospective Study.

Aims/Background Pregnancy may cause physiological and pathological changes in multiple organs in a woman's body, including the heart, liver, and eyes. With rapid advances in societies and economies, the proportion of advanced maternal age (AMA) women has significantly increased. Here, we aimed to investigate the changes in arteriole retinal diameter, venule diameter, macular layer thickness, and arteriole to venule ratio (AVR) in this population. Methods This retrospective case-control study included 523 pregnant women (1046 eyes) and was performed on both eyes. In total, 318 subjects were included in the AMA group, and 205 subjects were included in the non-AMA group. Nonmydriatic fundus photography and optical coherence tomography (OCT) were performed on the same day, and the results were analyzed for the central retinal arteriolar equivalent (CRAE), central retinal venular equivalent (CRVE), AVR, and macular thickness (9 subfields) by integrative vessel analysis and automatic OCT software. Results In both eyes, the CRAE was significantly lower in the AMA group than that in the non-AMA group (p < 0.05; respectively). The CRVE in the AMA group was higher than that in the non-AMA group (p < 0.001; respectively). Compared to the non-AMA group, the AMA group exhibited a significant reduction in macular thickness within the inner nasal, outer nasal, and inner temporal subfields of both eyes (p < 0.05; respectively). Age was significantly correlated with CRVE and AVR in both eyes of pregnant women (CRVE: p < 0.0001; AVR: p < 0.01). Conclusion This study reports variations in the diameter of the retinal vasculature and the thickness of the macula in women of AMA. It is important to consider these changes when interpreting the adverse eye outcomes experienced by women of AMA.

A Self-Compensating Non-Intrusive Ring-Type AC Voltage Sensor Based on Capacitive Coupling

In order to reduce the influence of coupling capacitance variations on cable voltage measurement, this paper proposes a self-compensating non-intrusive ring-type AC voltage sensor based on capacitive coupling. A theoretical model of the sensor was established, and the influence of parasitic capacitance changes on sensor output was analyzed. Furthermore, a theoretical analysis shows that the parasitic capacitance between the external cable and the sensing probe, as well as between the ground and the sensing probe, will significantly affect the sensitivity of the sensor and increases the measurement error. A ring-type inductive probe and a signal processing circuit were designed, incorporating a reference signal to compensate for the influence of coupling capacitance variations. Additionally, to minimize the impact of parasitic capacitance on sensor output, the length of the outer ring electrode was extended, and a PTFE housing was designed for protection. A prototype of the sensor was developed and tested. This prototype has a good linear response to AC voltage in the measurement range of 0–1000 V with a linearity of 0.86%. The effects of changes in cable diameter and cable position on the measurement were tested separately. The worst-case error of the sensor output is less than 6.44%, representing a reduction of 21.4% compared to the uncompensated case. Under external cable interference, the sensor exhibited an output error of less than 1.85%. The results show that the designed sensor can accurately measure cable voltage despite changes in cable diameter or installation position, and also demonstrates effective shielding against external interference.

Virtual patient analysis identifies strategies to improve the performance of predictive biomarkers for PD-1 blockade

Patients with metastatic triple-negative breast cancer (TNBC) show variable responses to PD-1 inhibition. Efficient patient selection by predictive biomarkers would be desirable but is hindered by the limited performance of existing biomarkers. Here, we leveraged in silico patient cohorts generated using a quantitative systems pharmacology model of metastatic TNBC, informed by transcriptomic and clinical data, to explore potential ways to improve patient selection. We evaluated and quantified the performance of 90 biomarker candidates, including various cellular and molecular species, at different cutoffs by a cutoff-based biomarker testing algorithm combined with machine learning-based feature selection. Combinations of pretreatment biomarkers improved the specificity compared to single biomarkers at the cost of reduced sensitivity. On the other hand, early on-treatment biomarkers, such as the relative change in tumor diameter from baseline measured at two weeks after treatment initiation, achieved remarkably higher sensitivity and specificity. Further, blood-based biomarkers had a comparable ability to tumor- or lymph node-based biomarkers in identifying a subset of responders, potentially suggesting a less invasive way for patient selection.

Mitral annular dynamics after transcatheter edge-to-edge repair for functional mitral regurgitation: comparison with surgical annuloplasty

Abstract Background Transcatheter edge-to-edge repair (TEER) is a recently emerged therapeutic option for functional mitral regurgitation (FMR). Although the mitral annular shape and function may play an important role in the pathophysiology of FMR, few reports have evaluated the impact of TEER. We sought to investigate the impact of TEER on the mitral annulus and its motion in FMR compared with that of mitral annuloplasty (MAP). Methods Using three-dimensional transesophageal echocardiography, we evaluated the mitral annular morphology and dynamic motion in patients who underwent TEER or MAP before and after the procedures. Mitral annulus analysis was performed by a semi-automatic program to create a dynamic model of the three-dimensional structure, where the end-systolic annular structure was semi-automatically annotated and manually corrected, followed by automatic tracking of the annulus throughout the cardiac cycle . The mitral annular parameters such as mitral annular diameters, area, circumference, and height at all frames were automatically calculated from the model. In order to align the cardiac phase in each patient (i.e. to set the start and the end of diastole and systole at the same time for all patient), data were spline-interpolated to 100 systolic and 200 diastolic frames and then statistically analyzed. The dynamic changes of the parameters during the cardiac cycle were calculated as (maximum – minimum value) / maximum value after the interpolation. Results Patients who underwent TEER (n=20, 69±15 years, 40% female) and those who underwent MAP (n=16, 64±11 years, 6% female) had similar echocardiographic characteristics before the procedures. The maximum anteroposterior diameter and annulus area decreased after both TEER and MAP, while the intercommissural diameter decreased only after MAP but not after TEER. After TEER, the dynamic change in anteroposterior diameter throughout the cardiac cycle tended to decrease (p=0.055), while intercommissural change rather increased (p=0.049), resulting in preserved change in annulus area (p=0.74). After MAP, changes in both diameters and area decreased significantly (all p&amp;lt;0.05). MAP was associated with postoperative mitral annulus area immobility after adjustment (p=0.030). Conclusions The dynamic motion of the mitral annulus in patients with FMR was better preserved after TEER than after MAP. There was a decreasing trend in anteroposterior motion, which was compensated for by intercommissural motion after TEER. Future studies are needed to determine the association of these results with cardiac function and prognosis.

Towards Regulations of Decommissioning Exhausted Water and Sewer Pipelines with Residues

The article provides a justification for the need to develop requirements for hydraulic characteristics of water and sewer pipes with internal deposits, that are absent in current regulations. The absence of such requirements leads to a change in the actual inner pipe diameter, flow rate and pressure losses, higher energy consumption of the pumping equipment.Purpose: To develop quantitative requirements for residue layer thickness on the inner surface of exhausted water and sewer pipes to substantiate their decommissioning.Methodology/approach: The quantitative method is used to assess the pipe operation efficiency according to the hydraulic criterion with the analysis of their hydraulic potential.Research findings: Quantitative values are proposed for the operational efficiency of exhausted pipelines according to which the residual pipe operation is determined to justify their decommissioning. Research findings will allow organizations to make decisions on decommission of exhausted engineering networks.Value: The developed proposals can be introduced in construction rules 31.13330.2021 and 32.13330.2018, justifying the need to decommission exhausted water and sewer pipelines with residues.

Point of care ultrasound measurement of paralumbar caudal vena cava diameter and caudal vena cava to aortic ratio in hypovolemic dogs

BackgroundAccurate assessment of intravascular volume is critical for precise fluid prescription. In people, bedside or point of care ultrasound is used to measure the inferior vena cava, with or without paired aortic measurement, to estimate intravascular volume.ObjectiveTo determine if point of care ultrasound measurement of the caudal vena cava (CVC) diameter or the CVC diameter to the abdominal aorta (Ao) diameter (CVC:Ao) at the paralumbar view are associated with changes in intravascular volume, mean arterial pressure (MAP), or cardiac output in normovolemic and hypovolemic dogs.Animals8 purpose-bred dogs.MethodsPressure-targeted hemorrhagic shock was induced in purpose-bred dogs under general anesthesia. Dogs were exsanguinated to a mean arterial pressure of 40 mmHg, or a maximum 60% blood volume lost, then auto-transfused shed blood. At a left paralumbar view, longitudinal plane measurements of the abdominal CVC diameter and aortic diameter were obtained. Measurements were performed at 4 timepoints: baseline under anesthesia (TP1), after hemorrhagic shock was induced (TP2), after ½ of shed blood had been re-transfused (TP3), and post-resuscitation with completed re-transfusion (TP4). Additional variables collected included cardiac output using thermodilution and arterial blood pressure.ResultsCVC:Ao was not significantly different between timepoints and was not associated with changes in CO (p = 0.28) or MAP (p = 0.50). CVC diameter was significantly different between baseline (TP1) and hemorrhagic shock (TP2). CVC diameter was significantly different at TP2 compared to TP1 after controlling for the effect of CO (p = 0.03) and MAP (p = 0.001). Aortic diameter was also significantly different at TP2 (p = 0.002, p = 0.001) and TP3 (p = 0.023, p = 0.017) compared to TP1 after controlling for CO and MAP.Conclusions and clinical importanceObtaining point of care ultrasound images for CVC:Ao measurement was feasible. With a marked decrease in intravascular volume, both CVC and Ao diameter decreased, resulting in an unchanged CVC:Ao. Despite changes in CVC and Ao diameters, these changes were not associated with measured changes in CO, emphasizing that CO is not a direct estimate of intravascular volume and is affected by many compensatory mechanisms. Additional studies are needed to determine the most accurate method for bedside measurement of intravascular volume status.

Safe and favorable prognosis of thoracic endovascular aortic repair for the low-risk patients with non-acute type B aortic dissection

ObjectivePreemptive thoracic endovascular aortic repair (TEVAR) has the potential to improve the prognosis of Stanford type B aortic dissection (TBAD), however it is important to determine whether it could be safely performed as a prophylactic treatment. This study aimed to determine the short- and long-term outcomes of preemptive TEVAR for uncomplicated TBAD with a small aortic aneurysm.DesignRetrospective multicenter analysis.MethodsWe analyzed 212 patients with medically treated uncomplicated subacute TBAD between July 2004 and October 2019 in two Japanese academic centers. The short- and long-term prognosis of patients who underwent preemptive TEVAR and the changes in aortic diameter over time after TEVAR were analyzed. Aorta-related complications, aortic-related death and postoperative complications were recorded and analyzed. Analysis was performed on an intension-to-treat basis.ResultsDuring follow-up, patients were divided into two groups: optimal medical treatment [OMT; n = 185 (87%)] and preemptive TEVAR [n = 27 (13%)]. In all cases, aortic enlargement was the reason for therapeutic intervention in the preemptive TEVAR group. Propensity score matching yielded a cohort of 27 control patients with OMT (group A) and 27 patients who underwent preemptive TEVAR (group B). Preoperative characteristics were similar between groups. In group B, only one patient developed type A dissection at a late stage and died from aortic rupture. Freedom from aortic-related death at 1/5/10 years was 100%/92%/92% in group B. Overall growth (mm/year) of max aorta was significantly smaller in the TEVAR group than in the control group (−3.7 ± 2.9 vs. 0.4 ± 5.6, p &amp;lt; 0.01), and the diameter of the false lumen was reduced (−8 ± 4.8 vs. −1.3 ± 8.0, p &amp;lt; 0.001).ConclusionsShort- and long-term outcomes of TEVAR for uncomplicated TBAD with a small aortic aneurysm were excellent, with few postoperative complications. After TEVAR, aortic remodeling was observed in the short term, suggesting that it may contribute to the prevention of aortic-related death due to rupture.

Using anginal symptoms to predict underlying etiology in patients with angina and no obstructive coronary disease (ANOCA)

Abstract Background Patients with angina with no obstructive coronary disease (ANOCA) can present with exertional anginal symptoms or angina at rest. Invasive coronary functional angiography (CFA) is used to diagnose endothelial-dependent and independent coronary microvascular dysfunction (CMD), microvascular spasm, and epicardial spasm. Historically, the type of anginal symptoms has been thought to be suboptimal in predicting the etiology of ANOCA. However, the sensitivity, specificity, predictive value, and correlation of angina type related to CFA abnormalities are unknown. We hypothesize that patients with predominantly exertional angina are more likely to have endothelial-independent and dependent CMD, and patients with angina at rest are more likely to have microvascular or epicardial spasm. Objective To explore sensitivity, specificity, predictive value, and correlation of angina type with underlying etiology of ANOCA as diagnosed by CFA. Methods A prospective registry-based cohort study of consecutive CFA performed in 197 ANOCA patients between 2020 and 2023 using the Doppler-tipped guidewire method. ANOCA was defined as &amp;lt;50% stenosis in any major epicardial artery at time of CFA. Patients were classified based on CFA diagnosis: (1) endothelial-independent CMD (coronary flow reserve [CFR] &amp;lt; 2.5 in response to adenosine), (2) endothelial-dependent CMD (coronary blood flow [CBF] &amp;lt; 50% or no change in vessel diameter in response to 54mcg intracoronary acetylcholine), (3) microvascular (&amp;lt;90% constriction) and epicardial spasm (&amp;gt;90% constriction) to 108 mcg intracoronary acetylcholine. Patients were categorized based on anginal symptoms (exertional angina or at rest angina) documented at cardiologist visit prior to CFA. McNemar’s test and Spearman correlations were performed for both types of angina and the 3 ANOCA underlying diagnoses. Results Among 197 ANOCA patients, the average age was 56.5 ± 11.9 years and 91% were female. Angina at rest had a high specificity (91.3%) but a low sensitivity (25.2%) for the diagnosis of spasm with a PPV of 90.5 (Table 1). There was a significant correlation between angina at rest and spasm (p=0.012). Angina at rest had a similarly intermediate sensitivity and specificity for endothelial independent and dependent CMD. Exertional angina had similar sensitivity, specificity, and a high PPV for endothelial independent and dependent CMD. There was a significant correlation between exertional angina and endothelial dependent CMD (p=0.025). McNemar’s test was statistically significant (p&amp;lt;0.001) for all analyses. Conclusion ANOCA patients with symptoms of angina at rest had a significant correlation with coronary spasms and exertional angina correlates with endothelial-dependent CMD. We demonstrate that angina at rest can be 90% specific for the diagnosis of spasm. Our findings warrant further investigation but suggest that empiric therapy based on angina type is a reasonable first step before invasive testing.

Evaluation of coronary microvascular dysfunction and vasospasm in patients with angina and non-obstructive coronary artery disease

Abstract Background Angina in the absence of obstructive coronary artery disease (CAD) is a growing cause of morbidity and mortality, exceeding the economic burden of CAD. Roughly 50-70% of patients undergoing invasive angiography for anginal symptoms have non-obstructive CAD. Within this category, there are distinct sub-populations including patients with angina without evidence of ischemia on prior stress testing (ANOCA), evidence of ischemia on stress testing (INOCA), or history of obstructive CAD with prior revascularization (ANOCA-HxCAD). Coronary microvascular dysfunction (CMD) and/or epicardial vasospasm are common causes of angina in the absence of epicardial CAD despite optimal medical therapy. Differences between these groups, in terms of risk factors and diagnoses remain relatively unknown. Purpose To compare clinical characteristics, symptoms, and diagnoses between patients with ANOCA, INOCA, and ANOCA-HxCAD. Methods In a prospective registry-based cohort study of 306 patients without obstructive CAD (&amp;lt;50% stenosis in epicardial artery) undergoing coronary functional angiography (CFA), we assessed differences in clinical characteristics, symptoms, and CFA diagnoses: (1) endothelial-independent CMD (coronary flow reserve [CFR] &amp;lt;2.5) to adenosine testing, (2) endothelial-dependent CMD (coronary blood flow [CBF]&amp;lt;50% or no change in vessel diameter to 54 mcg intracoronary acetylcholine [ACH]), (3) epicardial vasospasm to 108 mcg intracoronary ACH in 3 groups of patients (ANOCA, INOCA, and ANOCA-HxCAD). Results Among the 306 patients undergoing CFA, 89% were female with a median age of 58 years (49, 67). Patients with ANOCA-HxCAD had a significantly higher prevalence of hypertension, diabetes, heart failure with preserved ejection fraction, and experienced worse dyspnea on exertion as measured by University of San Diego Shortness of Breath (UCSD SOB) in comparison to ANOCA or INOCA patients. However, there were no differences between the groups in terms of anginal severity, functional capacity, or quality of life. In terms of CFA diagnoses, vasospasm was more prevalent in ANOCA-HxCAD (p&amp;lt;0.001) and CMD was more prevalent in ANOCA and INOCA patients (p=0.034) (Table 1). Conclusions Despite differences in clinical characteristics, patients without obstructive CAD have similar anginal severity, functional capacity, and quality of life regardless of evidence of ischemia on prior stress imaging or history of revascularization. There are differences in CFA diagnoses with higher prevalence of CMD in ANOCA and INOCA patients and higher prevalence of vasospasm in ANOCA-HxCAD patients. Determining the underlying diagnoses changes clinical management; therefore, CFA should be considered in all patients without obstructive CAD.

Differences in clinical characteristics, angina, and quality of life among patients with microvascular vs vasospastic angina and no obstructive coronary artery disease (ANOCA)

Abstract Background In patients with angina and no obstructive coronary disease (ANOCA), the underlying pathophysiology includes microvascular angina (endothelial-dependent and independent coronary microvascular dysfunction (CMD)) and vasospastic angina (microvascular spasm and epicardial spasm) diagnosed with invasive coronary functional angiography (CFA). However, whether there are differences in demographics, clinical characteristics, and outcomes by underlying diagnosis is unknown. We hypothesize that microvascular angina patients will be older and have more cardiovascular risk factors and worse outcomes than the vasospastic angina group. Objective To explore the differences in demographics, risk factors, and outcomes in ANOCA patients with microvascular and vasospastic angina. Methods A prospective registry-based cohort study of consecutive CFA was performed in 156 ANOCA patients between 2020 and 2023 using the Doppler-tipped guide wire method. Patients were classified into microvascular angina, vasospastic angina, and mixed disease. Microvascular angina was defined as endothelial-independent CMD (coronary flow reserve [CFR] &amp;lt; 2.5 in response to adenosine) and/or endothelial-independent CMD (coronary blood flow [CBF] &amp;lt; 50% or no change in vessel diameter in response to 54 mcg intracoronary acetylcholine). Vasospastic angina as microvascular (&amp;lt;90% constriction) and epicardial spasm (&amp;gt;90% constriction) to 108 mcg intracoronary acetylcholine. The mixed disease group included microvascular and vasospastic angina. Validated questionnaires evaluated angina (SAQ-7), functional capacity (DASI), dyspnea severity (UCSD SOB), and perceived stress (PSS) were obtained from patients at office visits prior to undergoing CFA. Results Among 156 ANOCA patients, 114 had microvascular angina, 10 had vasospastic angina, and 32 had mixed disease. The average age was 58.5 (SD 11.2) years. Demographics and prevalence of risk factors, such as hypertension, hyperlipidemia, or diabetes, showed no significant differences among the microvascular, vasospastic, or mixed disease groups. The prevalence of heart failure with preserved ejection fraction (HFpEF) was high across the groups, and outcomes did not differ significantly among them. The SAQ-7 score average ranged from 16.9 to 40.3, consistent with moderate to severe angina, and the DASI score ranged from 32.2 to 34.9, consistent with moderate functional capacity. Dyspnea severity ranged from 30 to 41, consistent with low to moderate severity, and perceived stress ranged from 11.5 to 13, consistent with low to moderate stress among all participants. Conclusion In patients with ANOCA undergoing invasive CFA, demographics, cardiovascular risk factors, and outcomes were similar regardless of underlying diagnosis. We demonstrate a high prevalence of risk factors and HFpEF and evidence of moderate to severe symptoms and functional capacity in ANOCA patients across all diagnoses.Abbreviation explanation for table 1

Right ventricular remodelling and long-term survival after pulmonary endarterectomy versus balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension.

Pulmonary endarterectomy (PEA) is the treatment of choice for chronic thromboembolic pulmonary hypertension (CTEPH), while balloon pulmonary angioplasty (BPA) is an alternative for inoperable patients. We aimed to compare right ventricular (RV) remodelling and late survival after PEA and BPA. In this prospective observational cohort study, we performed echocardiography at baseline and follow-up in patients with CTEPH treated with PEA (n=54) or BPA (n=44) between 2011 and 2022. Follow-up echocardiography was performed at 5 months (IQR 4-7) after PEA and 3 months (IQR 2-4) after the last BPA. Both groups showed significant improvements in left ventricular end-systolic eccentricity index, RV basal diameter and RV fractional area change (RV FAC). Tricuspid regurgitation pressure decreased by 26±18 mm Hg after PEA and 13±21 mm Hg after BPA (p=0.02 for between-group difference). Tricuspid annular systolic excursion (TAPSE) decreased by 4±5 mm after PEA but increased by 1±4 mm after BPA (p<0.001). The TAPSE/systolic pulmonary artery pressure ratio improved similarly in both groups. Five-year survival was 96% (95% CI 86% to 99%) for PEA and 79% (95% CI 61% to 89%) for BPA (p=0.25). Change in RV FAC was an independent predictor of survival (HR 0.9, 95% CI 0.82 to 0.99, p=0.03). Both PEA and BPA led to significant RV reverse remodelling, with no clear evidence of a difference in survival rates. Improvement in RV function, particularly RV FAC, was associated with better outcomes, highlighting the importance of RV recovery in CTEPH treatment.

Lipin1 prevents ischemic heart disease by regulating lipid homeostasis

Abstract Background Lipid metabolism plays a crucial role in the pathophysiology of cardiovascular diseases. Lipin1 plays a pivotal role in lipid metabolism regulation. In the nucleus, Lipin1 acts as a transcriptional co-stimulatory molecule, interacting with peroxisome proliferator–activated receptor–gamma coactivator 1 alpha (PGC1α) and peroxisome proliferator–activated receptor alpha (PPARα). In the cytoplasm, Lipin1 functions as a phosphatidate phosphatase, converting phosphatidic acid to diacylglycerol to regulate lipid metabolism. Low expression of Lipin1 has been implicated in the severity of cardiac dysfunction in mice. Purpose This study aimed to investigate the role of Lipin1 in the cardiac remodeling after myocardial infarction (MI), revealing its impact on lipid metabolism and molecular pathway associated with cardiac dysfunction. Methods Two types of transgenic mice, cardiomyocyte-specific Lipin1 knockout (cKO) and overexpression (cOE) mice were used in this study. Eight to ten-week-old male mice were subjected to MI by coronary artery ligation. Cardiac lipid droplets were quantified, and triacylglycerol and free fatty acid levels were measured one week after MI surgery. Four weeks after MI, cardiac morphology and function were evaluated using echocardiography, alongside measurements of body weight (BW) and heart weight (HW). Additionally, gene expression analysis and histological evaluation were conducted to assess fatty acid metabolism, cardiac fibrosis, inflammation, and oxidative damage. Results Before MI surgery, there were no differences in HW/BW ratio, left ventricular end-diastolic diameter (LVDd) or LV fractional area change (LVFAC) among cKO/ cOE mice and their littermate controls. After MI, cKO mice exhibited significant cardiac dysfunction with larger LVDd, lower LVFAC and increased HW/BW ratio compared to littermate controls. This was accompanied by exacerbated cardiac fibrosis, increased inflammation, and augmented reactive oxygen species accumulation compared with their controls. Conversely, cOE mice displayed improved LVFAC, reduced cardiac fibrosis, inflammation, and reactive oxygen species accumulation compared to their littermate controls. Notably, the transgene of Lipin1 induced changes in the number of cardiac lipid droplets (LDs). cKO mice hearts showed a reduction in cardiac LDs with decreased levels of triacylglycerol and free fatty acids compared to the littermate controls. In contrast, cOE mice displayed increased cardiac LDs and upregulated expression of fatty acid metabolism–related genes after MI. Conclusion These results suggested that Lipin1 has a protective role against ischemic injury through controlling lipid metabolism in ischemic cardiomyocytes. Thus, Lipin1 emerges as a potential therapeutic target for myocardial infarction.

Left ventricular apical aneurysms and outcomes in hypertrophic cardiomyopathy

Abstract Background/Introduction The presence of left ventricular apical aneurysm (LVAA) has been shown to be associated with increased risk of adverse events in patients with hypertrophic cardiomyopathy (HCM). However, the between LVAA size and outcomes is uncertain. Purpose To explore associations between baseline LVAA diameter and progressive changes in LVAA size over time and poor outcomes in HCM patients. Methods Our HCM multimodality imaging database (transthoracic echocardiography (TTE) or cardiac magnetic resonance (CMR)) was retrospectively assessed for studies reporting LVAA, defined as one or more akinetic or dyskinetic apical segments. LVAA size (widest systolic diameter in millimetres in the transverse plane) was recorded at two time points: earliest identification and most recent imaging, with LVAA size progression (mm/year) calculated. Patients’ electronic records were reviewed for composite outcome including stroke, apical thrombus, death, and appropriate therapy from implantable cardioverter defibrillator (ICD). Continuous variables are presented as mean ± standard deviation (SD), categorical data numerically or as percentages. Comparisons between groups were made using Wilcoxon ranks sum and Fischer exact test for continuous and binary variables, respectively. Cox regression was used to assess independent associations with composite outcomes. A p value of &amp;lt;0.05 was considered statistically significant. Results A total of 106 patients were identified with LVAA and clinical follow-up (mean age 64.7±11.4 years, 70% male). Mean follow-up duration was 6.5±3.0 years. Baseline LVAA was confirmed by CMR and TTE in 70 and 30% of cases respectively. Mean LVAA size at baseline was 16.2±7.6 mm (range 6-56 mm). During multivariate Cox analysis, baseline LVAA size in mm was independently associated with the composite outcome (HR 1.04, 95% CIs 1.0 to 1.08, p=0.04). Mean duration between baseline and maximal LVAA size scan was 5.4±3.0 years. Median progression in LVAA size was 1.0 (IQR 0.6 to 1.8) mm per annum (range 0.0 to 8.1 mm). During multivariate analysis, LVAA progression rate in mm per year was independently associated with the composite outcome (HR 1.4 95% CIs 1.11 to 1.7, p=0.002). Conclusion(s) These data support the association between LVAA size and poor outcomes in HCM patients. We also demonstrate the progressive nature of LVAAs and indicate those more rapidly increasing in size are at highest risk of adverse events, with potential implications for management strategies.

Numerical study on structural design and mechanical analysis of anti-migration tracheal stent with non-uniform Poisson's ratio

Stent migration is one of the common complications after tracheal stent implantation. The causes of stent migration include size mismatch between the stent and the trachea, physiological movement of the trachea, and so on. In order to solve the above problems, this study designed a non-uniform Poisson ratio tracheal stent by combining the size and structure of the trachea and the physiological movement of the trachea to improve the migration of the stent, meanwhile ensuring the support of the stent. In this study, the stent corresponding to cartilage was constructed with negative Poisson's ratio, and the stent corresponding to the circular connective tissue and muscular membrane was constructed with positive Poisson's ratio. And four kinds of non-uniform Poisson's ratio tracheal stents with different link lengths and negative Poisson's ratio were designed. Then, this paper numerically simulated the expansion and rebound process of the stent after implantation to observe the support of the stent, and further simulated the stretch movement of the trachea to calculate the diameter changes of the stent corresponding to different negative Poisson's ratio structures. The axial migration of the stent was recorded by applying different respiratory pressure to the wall of the tracheal wall to evaluate whether the stent has anti-migration effect. The research results show that the non-uniform Poisson ratio stent with connecting rod length of 3 mm has the largest diameter expansion in the negative Poisson ratio section when the trachea was stretched. Compared with the positive Poisson's ratio structure, the axial migration during vigorous breathing was reduced from 0.024 mm to 0.012 mm. The negative Poisson's ratio structure of the non-uniform Poisson's ratio stent designed in this study did not fail in the tracheal expansion effect. Compared with the traditional stent, the non-uniform Poisson's ratio tracheal stent has an anti-migration effect under the normal movement of the trachea while ensuring the support force of the stent.

Analysis and design of wire winding tension control system based on genetic algorithm and fuzzy PID

Wire winding is a key process in transformer manufacturing, and the accuracy of tension control directly affects the quality of the products. To achieve the requirement of constant tension winding of wire, the influence of roll diameter, speed, and other factors on the dynamic performance of tension is analyzed by establishing the dynamic model of unwinding and winding as well as the pendulum part. A control strategy combining proportional-integral-derivative (PID) control with fuzzy control is adopted, and the parameters of the fuzzy PID controller are optimized using an improved genetic algorithm. Simulation results demonstrate that the optimized fuzzy PID controller significantly reduces tension overshoot and effectively suppresses the tension fluctuation when the speed and roll diameter change, and the tension fluctuation is controlled within 2%. Finally, the feasibility of the optimized fuzzy PID controller in the tension control system is experimentally validated.

Hydrodynamic Cavitation‐Induced Thrombolysis on a Clot‐on‐a‐Chip Platform

Complications from thrombosis constitute a massive global burden for human health. Current treatment methods have limitations and can cause serious adverse effects. Hydrodynamic cavitation (HC) is a physical phenomenon where bubbles develop and collapse rapidly within a moving liquid due to sudden pressure changes. These collapsing bubbles provide high targeted energy which can be used in a controlled environment with the help of microfluidic devices. This study introduces a new clot‐on‐a‐chip (CoC) platform based on HC, evaluated for thrombolysis efficacy. The microfluidic device, paired with a polydimethylsiloxane (PDMS) microchip, generates cavitation bubbles at low upstream pressures (≤482 kPa), enabling microscale blood clot erosion. Different HC exposure conditions (varying pressure and duration) are assessed by changes in clot mass, diameter, and scanning electron microscopy (SEM). The largest mass reduction occurs at 482 kPa for 120 s, with a decrease of 6.1 ± 0.12 mg, while the most erosion in diameter of blood clots is obtained 482 kPa for 120 s with complete removal. SEM results show increasing damage to clot structure from less to more intense HC exposures. The CoC platform, at controlled pressures and durations, efficiently disrupts clot structure and offers a promising drug‐free alternative for thrombolysis treatment.

Multi-scale modeling of aerosol transport in a mouth-to-truncated bronchial tree system

Computational fluid particle dynamics (CFPD) is widely employed to predict aerosol transport in a truncated bronchial tree model on account of its capacity to reveal details of flow field and particle movement. However, setting a physiologically consistent boundary condition in the CFPD for the idealized or image-based truncated bronchial tree model is still a challenge. This paper proposes a multi-scale modeling method, which contains an Extend-Bronchial tree-Network (EBN) boundary condition for a mouth-to-truncated bronchi system. The comparison between EBN boundary condition and a commonly used uniform pressure (UP) boundary condition is conducted. Subsequently, EBN method is used to study the nano-micron (100nm-10μm) particles transport in the mouth-to-truncated bronchi model at different inhalation volume rates (15, 60, 90L/min). Results show that EBN method is more physiologically rational and two methods differ in flow distribution in lobes, vortex structure, and particle transport. The maximum difference in flow rate distribution in lobes between two methods is about 20%, while the maximum relative disparity of particle penetration fraction from lobes and deposition fraction in the TLB is about 93% and 30%, respectively. Meanwhile, this paper reveals the variation of deposition fraction and penetration fraction with the changes in particle diameter and inhalation volume. Deposition efficiency, deposition hotspots and deposition mechanism are also analyzed with inlet Stokes number (Stk) and Reynolds number (Re). This research establishes a foundation for the simulation of aerosol transport in a whole respiratory tract and provides references for inhalation drug delivery and air pollutant management.

True pinch mode of magnetorheological fluids

Abstract Magnetorheological (MR) fluids are representatives of smart materials. They react to magnetic fields by developing a yield stress. The effect has been employed in real-world applications such as automotive chassis systems or optical finishing. By convention, MR devices can be operated in at least one of the fundamental modes: flow, shear, squeeze, gradient pinch of which the former has been the least studied and understood. In pinch mode, the material in the flow channel is exposed to non-uniform magnetic fields in the direction parallel to fluid flow. As a result, only the volume of MR fluid near the channel walls are energized to modify the particular material property (yield stress). The result is the channel’s effective diameter change. The behavior of the material in pinch mode is unique and unseen in the other controllable fluids. To study the material’s characteristics in the specific mode, the authors developed a novel circuit concept for energizing the material in an effort to achieve the ’true-zero’ pinch mode magnetic behavior. Contrary to the existing pinch mode valve concepts, the concept valve allows to achieve zero magnetic flux density in the center of the flow channel regardless of the current level. To test the hypothesis a prototype valve was modeled, manufactured and tested across a range of external (flow rate, current/magnetic flux) stimuli. The obtained results yield sufficient evidence proven by results of magnetic simulations to support the underlying hypothesis. The experimental results illustrate the pinch mode type behaviour, i.e. the slope change in the pressure vs flow rate characteristics.&amp;#xD;

The Implications of Aging on Vascular Health.

Vascular aging encompasses structural and functional changes in the vasculature, significantly contributing to cardiovascular diseases, which are the leading cause of death globally. The incidence and prevalence of these diseases increase with age, with most morbidity and mortality attributed to myocardial infarction and stroke. Diagnosing and intervening in vascular aging while understanding the mechanisms behind age-induced vascular phenotypic and pathophysiological alterations offers the potential for delaying and preventing cardiovascular mortality in an aging population. This review delves into various aspects of vascular aging by examining age-related changes in arterial health at the cellular level, including endothelial dysfunction, cellular senescence, and vascular smooth muscle cell transdifferentiation, as well as at the structural level, including arterial stiffness and changes in wall thickness and diameter. We also explore aging-related changes in perivascular adipose tissue deposition, arterial collateralization, and calcification, providing insights into the physiological and pathological implications. Overall, aging induces phenotypic changes that augment the vascular system's susceptibility to disease, even in the absence of traditional risk factors, such as hypertension, diabetes, obesity, and smoking. Overall, age-related modifications in cellular phenotype and molecular homeostasis increase the vulnerability of the arterial vasculature to structural and functional alterations, thereby accelerating cardiovascular risk. Increasing our understanding of these modifications is crucial for success in delaying or preventing cardiovascular diseases. Non-invasive techniques, such as measuring carotid intima-media thickness, pulse wave velocity, and flow-mediated dilation, as well as detecting vascular calcifications, can be used for the early detection of vascular aging. Targeting specific pathological mechanisms, such as cellular senescence and enhancing angiogenesis, holds promise for innovative therapeutic approaches.

Endovascular treatment of aortic coarctation using covered balloon-expandable stents-a systematic review and meta-analysis.

Balloon dilation followed by balloon-expandable stent implantation is an effective treatment for improving hemodynamic status in patients with coarctation of the aorta (CoA). However, limited evidence exists regarding the safety and efficacy of covered balloon-expandable stents (CBSs) in a large cohort. In this meta-analysis, we aimed to evaluate the overall success rates, hemodynamic and anatomical benefits, complications, and mid-term results of CBSs in treating CoA. The PubMed, Embase, and Cochrane Library databases were systemically searched for studies reporting outcomes of CBSs in treating CoA. Single-group rate meta-analyses were performed to calculate estimated pooled procedural success rates, the incidence of complications, and re-coarctation rates. A meta-analysis using standardized mean differences was conducted to compare pre- and postoperative trans-coarctation pressure gradients (PGs), coarctation diameter, and overall changes in systolic blood pressure (SBP). Subgroup analyses were performed to identify potential sources of heterogeneity. The final analysis included 12 studies with a total of 411 patients. The estimated pooled procedural success rate was 100% [95% confidence interval (CI): 98%-100%, I2 = 0, P = 0.78]. Significant decreases in trans-coarctation PGs and SBP were observed. The pooled incidences of stent-related, aortic, and access site complications were 2% (95% CI: 0%-5%, I 2 = 30.4%, P = 0.15), 2% (95% CI: 0%-4%, I 2 = 0%, P = 0.76), and 3% (95% CI: 1%-7%, I 2 = 52.9%, P = 0.02), respectively. Subgroup analyses showed that implantation of BeGraft stents was related to a significantly higher incidence of access site complications. Covered balloon-expandable stent implantation in treating CoA is safe and effective with high procedural success rates, an acceptable incidence of complications, and a low incidence of re-coarctation. https://www.crd.york.ac.uk/PROSPERO/, PROSPERO (CRD42023430356).