Fractional Change Research Articles

Graft-derived cell free DNA: used for assessment of early graft status and its implications for long-term kidney function

BackgroundThe long-term graft survival is closely related to its early status, yet the indices for assessing the early graft status are complex and lack quantitative values. The aim of this study is to investigate the potential of GcfDNA as a comprehensive, non-invasive, convenient, and quantifiable indicator for evaluating early graft status.MethodsIn this study, 138 recipients who underwent primary kidney transplantation were enrolled. Peripheral blood samples, each 10 mL, were collected on days 1 and 7 post-transplantation. The quantification of both the graft cell-free DNA (GcfDNA) fraction (%) and GcfDNA concentration (copies per milliliter, cp/mL) was performed using droplet digital PCR (ddPCR).ResultsFor most recipients, both the GcfDNA fraction and concentration had a rapid decline at 7 days post-transplantation, reaching median values of approximately 0.7% and 53.5 cp/mL, respectively. No significant associations were found between GcfDNA values and other clinical parameters. On the seventh postoperative day, we observed a significant elevation in GcfDNA concentration among recipients with eGFR values < 60 mL/min/1.73 m2. Additionally, notable increases were identified in both GcfDNA fraction and concentration variations within this specific subgroup. The findings of our study indicate a negative correlation between the concentration and fractional changes of GcfDNA on postoperative days 1 and 7, as well as the GcfDNA concentration on postoperative day 7, with eGFR within the 1–2 years post-transplantation period. The ROC curve of GcfDNA_Copies_Variation. day1-day 7 showed the highest AUC value AUC = 0.8006, with high sensitivity (90.14%) and specificity (77.61%), and PPV and NPV were 81.01% and 88.14%, respectively. Using four classical algorithm models, we found that the xgboost regression model achieved the best predictive performance (area under the curve (AUC) values = 0.862) for eGFR within 1–2 years post-transplantation, with high sensitivity (85.7%) and specificity (85%).ConclusionThe changes of GcfDNA levels in the early stage are closely related to kidney function within 1–2 years post-transplantation. As a comprehensive indicator of graft function, GcfDNA has great potential for clinical application.

Fractional change of scattering and absorbing aerosols contributes to Northern Hemisphere Hadley circulation expansion.

The relative amount of scattering and absorbing aerosols is essential in determining the aerosol radiative and climate effects. Using reanalysis datasets and climate simulations, here, we show that changes in the relative amount of scattering and absorbing aerosols in the Northern Hemisphere (NH) high latitudes, manifested as long-term decreasing trends in aerosol single-scattering albedo (SSA), have played an important role in driving the widening and weakening trends of the NH Hadley circulation (HC) since the early 1980s. Decreasing SSA in the NH middle and high latitudes can notably warm the troposphere there, thus reducing the equator-to-pole temperature gradient, increasing static stability in mid-latitude regions, and leading to the widening and weakening trends of NH HC. Further analysis of the Coupled Model Intercomparison Project Phase 6 (CMIP6) aerosol forcing-only simulations also supports the importance of SSA trends in perturbing NH HC through the above mechanism.

Functional and imaging outcomes of the Fontan circulation following pregnancy.

The Fontan circulation palliates single-ventricle congenital heart disease by separating the systemic and pulmonary circulations. An increasing number of women with a Fontan circulation are wishing to become pregnant, however the ability to increase cardiac output during pregnancy is limited in many due to the chronic low output state. We describe pregnancy outcomes in these women at a large tertiary centre, including functional and imaging outcomes. We retrospectively investigated women with a Fontan circulation giving birth after 24 weeks' gestation between 1995 and 2023. Data collected included obstetric and neonatal complications, changes in cardiac volumes and ejection fraction (EF), and functional outcomes including change in NYHA class and exercise capacity pre- and post-pregnancy, compared to matched male controls. Twenty-six pregnancies occurred among 23 women. Almost half experienced obstetric complications, primarily bleeding, which was the commonest indication for emergency C-section. Worsening cardiac symptoms complicated 50 % of pregnancies, with 4 requiring hospital admission for decompensation. Arrhythmias were not uncommon. Mean VO2max declined post-pregnancy (p = 0.03), though not significantly compared to controls. Worsening of NYHA class was uncommon (15.4 %), suggesting that cardiovascular complications during pregnancy do not correlate with longer-term functional limitation. EF worsened post-pregnancy, declining significantly more so than in matched controls (p = 0.03), however there were no changes in cardiac volumes. Pregnancy in women with a Fontan circulation is associated with high rates of obstetric complications and worsening cardiac symptoms. However, successful pregnancies are possible, with little evidence of medium-term functional impairment. This data informs pre-pregnancy counselling of Fontan women of child-bearing age.

Studies of beam ion confinement to enhance plasma performance on EAST

A key physics issue for achieving steady-state high-performance plasmas on EAST tokamak is to decrease beam-ion losses to improve plasma confinement during neutral beam injections (NBIs). To decrease the beam losses, previous counter-I p NBI injections are upgraded to co-I p injections. Analysis shows that due to the reversed direction of drift across the flux surfaces caused by the pitch angle, the beam prompt loss fraction decreases from about 49% to 3% after the upgrade. Moreover, because of the change of entire beam path, beam shine-through (ST) loss fraction for counter-I p tangential and counter-I p perpendicular injections is reversed to co-I p tangential and co-I p perpendicular injections, respectively. Due to the change in the initial trapped-confined beam ion fraction caused by the peaked pitch profiles, the losses induced by toroidal ripple field are also reversed after the upgrade. To further improve the beam-ion confinement under the present NBI layout, the amplitudes of toroidal field are increased from 1.75 to 2.20 T. Result shows that, due to the smaller orbit width and peaked pitch angle profile, the beam prompt loss power is lower with higher toroidal field. Due to the synergy of higher initial trapped-confined beam ion fraction and narrower Goldston-White-Boozer (GWB) boundary, the loss induced by ripple diffusion is higher with higher toroidal field. The combined effect of beam ST loss, prompt loss and ripple loss, contributes to the increase in beam ion density. The decrease in beam loss power enhances beam heating efficiency, especially the fraction of beam heating ions. Finally, comparison between simulation and measurement by 235U fission chamber (FC) indicates that the increase in neutron rate is mainly contributed by improvement of beam-ion confinement. This study can provide potential support for beam operation and high-T i experiment on EAST tokamak.

Nonlinear model predictive controller of hydrogenation of dimethyl oxalate for ethylene glycol production

Abstract Ethylene glycol (EG) is a valuable commodity organic intermediate that is produced using the catalyzed gas-phase hydrogenation process of dimethyl oxalate (DMO) from syngas. The reactor process is challenging to control because of its nonlinearity and multivariable condition. Thus, this study proposes the application of Neural Wiener model predictive control (NWMPC) for DMO hydrogenation reactor control. The application of empirical-based MPC, such as NWMPC, is still new in DMO hydrogenation reactor control. In order to simulate the process, the DMO hydrogenation reactor is modeled using Aspen Plus and Aspen Dynamic software. The Neural Wiener (NW) model is developed based on state space and neural network modeling using a Linear-Nonlinear (L-N) identification approach. A validation test is also performed to verify the accuracy of the NW model. Based on the test, the model accuracy is acceptable with the coefficient of determination (R2) of 0.965 for EG output mole fraction (first output) and R2 of 0.936 for product temperature (second output). The NWMPC capability is evaluated with a PID controller to handle a setpoint change in EG output mole fraction and reject disturbance in the feed stream flow rate. The control performance results have demonstrated the superior ability of the NWMPC to handle such scenarios better than PID in terms of controller action speed and profile.

Abstract A025: Tumor fraction (TF) is associated with real-world progression-free survival (rwPFS) in advanced non-small-cell lung cancer (aNSCLC) patients treated with chemotherapy (chemo)

Abstract Background: Genomic ctDNA molecular response (gMR) predicts clinical benefit from immune checkpoint inhibitors, but associations with benefit from chemo are inconsistent. gMR may predict benefit from chemo after filtering to tissue-confirmed somatic variants, suggesting interference from clonal hematopoiesis (CH) mutations. Using methylation tumor fraction (TF) for MR assessment may mitigate the risk of CH interference without tissue and with higher sensitivity. Here, we report a retrospective study assessing the feasibility of using methylation- based TF from the Guardant Infinity platform to predict clinical benefit from chemo in a real- world cohort of patients (pts) with aNSCLC. Methods: Plasma samples were analyzed from pts (n=67) with aNSCLC, undergoing treatment with chemo only in 1st line or later setting, who had serial methylation TF results from tissue-free genomic and epigenomic ctDNA NGS. The present analysis included 27 pts with a baseline sample (T1) within 105 days prior to treatment start and an on-treatment timepoint (T2) 2-15 weeks after treatment start and >10 days prior to treatment end. gMR was based on the % change in mean variant allele fraction (VAF) T2/T1. TF % change was defined as TF (T2) / TF (T1). Relationships between time-to-next- treatment (TTNT; proxy for progression-free survival) and gMR or TF % change from T1 to T2 were explored using Cox proportional hazards (CPH) analysis. Multiple cutpoints were evaluated to label pts as molecular responders or non-responders for outcomes analysis. Gender, age, and therapy line were included as covariates for all analyses. Results: A ctDNA change from T1 to T2 was quantifiable in 85% of pts (18/27) by TF change versus 67% of pts by gMR due to improved limit of quantification for TF relative to somatic variants. CPH revealed that gMR defined by any ctDNA % change threshold was not associated with TTNT (p=(0.182- 0.862)). However, pts with a ≥95% decrease in TF from T1 to T2 had a significant association with improved TTNT (HR 0.14; 95% CI (0.03, 0.80); p=0.027). Furthermore, molecular responders defined by any decrease cutpoint >70% were significantly associated with improved TTNT (p≤0.033). Conclusions: A decrease in TF >70% early during chemotherapy was significantly associated with improved TTNT, even in this small cohort. The change in ctDNA was quantifiable in more patients by TF change than by gMR and included patients with no somatic variants detected. In contrast, gMR defined by any ctDNA % change threshold was not associated with TTNT. These results demonstrate feasibility of methylation-based TF to predict benefit from chemo in aNSCLC patients without tissue and with higher sensitivity than gMR, laying groundwork for future studies to address validity of serial TF monitoring in this patient population. Citation Format: Jing Wang, Sean Gordon, Errin Lagow, Tara Dinman, Carin Espenschied, Shile Zhang, Kimberly Banks. Tumor fraction (TF) is associated with real-world progression-free survival (rwPFS) in advanced non-small-cell lung cancer (aNSCLC) patients treated with chemotherapy (chemo) [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr A025.

Abstract 4137854: Effect of Sacubitril/valsartan on Left Ventricular Tissue Characterization in Heart Failure with Left Ventricular Ejection Fraction Below 50%

Background: The effects of sacubitril/valsartan (ARNI) on myocardial tissue characterization in heart failure (HF) with left ventricular ejection fraction (LVEF) <50% are still unclear. Objective: The present study investigated the effects of 9 months of ARNI treatment on LV structure and myocardial tissue characteristics in HF with LVEF <50% using cardiac magnetic resonance (CMR). Methods: This study was a prospective, 2-arm, randomized, open-label clinical trial (SAVE-HF). Sixty-four HF outpatients with LVEF<50% were randomized 1:1 from ACE inhibitor/ARB to ARNI (ARNI group) or control group (continued ACE inhibitor/ARB). CMR was performed to evaluate LV structure and tissue characteristics, including changes in LV extracellular volume fraction (delta ECV) before and after the 9-month period. The primary endpoint was difference in ECV between the two groups. Secondary endpoints included changes in LV volumes and mass, LVEF, extracellular mass (ECM) calculated as LV mass times ECV/100, and intracellular mass (ICM) calculated as LV mass minus ECM. Results: A total of 59 of 64 stable patients (68±12 years; 52 men) completed the 9-month intervention followed by repeated CMR. ARNI decreased systolic BP levels from the first month by approximately 10 mmHg. ARNI group exhibited significant reductions in LV end-diastolic and end-systolic volumes and LV mass. While LVEF and ECV remained unchanged (31.6±5.0 vs. 31.9±5.0%, p=0.26), both ECM and ICM significantly decreased after ARNI. In the control group, systolic BP, LV volumes and LV mass, ECV, ECM and ICM were unchanged. Comparing the two groups, while delta ECV was not significantly different, delta ECM was greater in ARNI group than control group (-3.6±7.3 vs. 0.2±5.3 g, p=0.025), indicating improved LV tissue characteristics. Conclusions: ARNI reduced LV volume and LV mass, accompanied with reduction of both ECM and ICM, and consequently unchanged ECV. These findings may suggest that ARNI may improve LV tissue characteristics and protect from LV remodeling in HF patients with their LVEF<50%.

Characteristics of soil organic carbon fractions and influencing factors in different understory mosses in karst urban parks.

The impact of different vegetation types on soil organic carbon (SOC) is a key focus in global warming research. Bryophytes, commonly found in karst urban forests, significantly contribute to carbon accumulation in surface soil. However, the changes in soil organic carbon fractions under moss and the influencing factors remain unclear. To address this knowledge gap, the study examined the organic carbon content, soil physicochemical properties, and associated environmental factors in both moss-covered soil and bare soil under six different forest species within an urban park. The results showed that the SOC contents under moss cover in evergreen coniferous forest (127.28g/kg), bamboo forest (144.70g/kg), deciduous broad-leaved forest (87.63g/kg), and evergreen shrub (109.28g/kg) were significantly higher compared to bare soil. Moss cover also had a significant impact on soil readily oxidizable carbon (ROC), particulate organic carbon (POC), mineral-associated organic carbon (MOC), and heavy fraction organic carbon (HFOC) (P < 0.01). The soil under moss had a higher content of stable organic carbon fraction, which is conducive to the stability of the soil organic carbon pool. The interaction between moss cover and stand type had the most significant effect on soil organic carbon, especially in bamboo forests. Canopy density, moss biomass, and soil moisture were the main environmental factors affecting the content of soil organic carbon and its fractions, while soil organic carbon content was mainly affected by soil nitrogen and phosphorus. This study establishes a theoretical framework for investigating the carbon cycle in karst urban underforest ecosystems, offering a scientific basis for the management and preservation of urban green space ecosystems. Future studies should include bryophytes in the assessment of dynamic factors affecting the soil carbon pool under forest cover and further explore the function and ecological significance of bryophytes in understory ecosystems.

Abstract 4135465: Efficacy of SGLT-2 inhibitors combined with percutaneous coronary intervention on clinical and echocardiographic parameters in patients with acute myocardial infarction: A systematic review and meta-analysis

Background: Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have shown benefits in improving cardiovascular outcomes in heart failure (HF) patients and may mitigate symptom progression in myocardial infarction (MI). However, their efficacy in acute MI patients undergoing percutaneous coronary intervention (PCI) is unclear. This study aims to evaluate whether SGLT2i combined with PCI improves clinical and echocardiographic outcomes. Methods: A comprehensive search of electronic databases, PubMed, Cochrane Central and SCOPUS was conducted from inception till May 2024. The study was conducted adhering to the PRISMA guidelines. The clinical benefit of PCI plus SGLT2i was assessed through risk reduction of acute kidney injury (AKI), CV death (CVD), hospitalization due to HF (hHF), all-cause mortality (ACM), and revascularization. Echocardiographic outcomes assessed were change in left ventricular ejection fraction (LVEF) and LV end-diastolic volume (LVEDV). Results were presented as risk ratios (RR) along with their 95% CI for dichotomous data while weighted mean difference (WMD) were reported for continuous outcomes. The data was aggregated using a random effects model. Results: Our analysis included eleven records comprising 6,411 participants. The results indicated that PCI plus SGLT2i significantly reduced the risk of AKI (RR: 0.66, 95% CI: [0.52, 0.83], p&lt;0.01) and ACM (RR: 0.54, 95% CI: [0.4, 0.7], p&lt;0.01) compared to PCI alone. However, the reduction in risk for CVD was not statistically significant (RR: 0.56, 95% CI: [0.2, 1.1], p=0.09), as was the case for hHF (RR: 0.65, 95% CI: [0.3, 1], p=0.07). Additionally, there was no significant difference in the risk of revascularization between the two groups (RR: 2.9, 95% CI: [0.62, 14.39], p=0.17). PCI plus SGLT2i was also significantly associated with an increase in LVEF (WMD: 2.73, 95% CI: [1.09, 4.36], p&lt;0.01) and decrease in LVEDV (WMD: -8.0, 95% CI: [-13.17, -2.90], p&lt;0.02). Conclusion: Our study demonstrates that SGLT2i administration in MI patients undergoing PCI leads to improved renal and mortality outcomes, along with enhanced cardiac function. These benefits are hypothesized to result from kidney-mediated natriuretic effects, improved blood flow regulation, reduced endothelial dysfunction, and decreased arterial stiffness, which optimize cardiac function. We recommend future studies with larger sample sizes and longer follow-ups to assess the long-term benefits of SGLT2i combined with PCI.

Abstract 4129182: Transendocardial Stem Cell Therapy Improves Cardiac Parameters in Chronic Ischemic Heart Failure: A Meta-analysis of Randomized Controlled Trials

Introduction: Despite recent advances in therapy, chronic ischemic heart failure remains a significant cause of morbidity and mortality worldwide. Stem cell (SC) therapy has recently emerged as a potential therapeutic approach, yet its efficacy remains debatable. We aimed to systematically review and meta-analyze the current evidence to evaluate its effectiveness. Methods: A comprehensive literature search was conducted across the following databases: PubMed, Embase, and Cochrane, from inspection to April 2024. We identified RCTs with a blinded study design, done on patients diagnosed with chronic ischemic HFrEF, and utilized mesenchymal stem cells as an intervention in comparison to placebo/sham intervention using percutaneous endomyocardial catheter systems. Meta-analysis was conducted using RevMan v5.4 to calculate the odds ratio (OR) at 95% confidence intervals (CI) and a p-value of 0.05. I 2 was indicated for the assessment of heterogeneity. Sensitivity analysis was done in case of heterogeneity between studies. Results: A total of twenty studies were included in our meta-analysis. The overall change in left ventricular end-systolic volume (LVESV) and stress SPECT significantly favored the stem cell group (pooled effect size -7.59, 95% CI [-12.28 to -2.89], P=0.002), and (pooled effect size -5.33, 95% CI [-6.73 to -3.93], P=0.00001), respectively. Initially, the change in left ventricular end-diastolic volume (LVEDV) did not favor either group. However, sensitivity analysis which excluded one study at a time, reduced heterogeneity (P=0.01, I 2 =54%) and showed a significant effect favoring the stem cell group (pooled effect size -3.87, 95% CI [-6.77 to -0.97], P=0.009). However, the overall changes in left ventricular ejection fraction (LVEF) did not favor either of the two groups (pooled effect size 0.08, 95% CI [-0.1 to 0.26], P=0.39). Similarly, the overall change in myocardial oxygen consumption (MVO2) did not favor either group (pooled effect size 0.66, 95% CI [-0.1 to 1.32], P=0.05). Conclusion: Transendocardial SC therapy demonstrates promising results by significantly improving specific cardiac parameters. While the therapy shows potential, particularly after sensitivity adjustments, its impact on other critical measures like LVEF and MVO2 remains inconclusive. These findings highlight the need for further investigation to fully understand and enhance the therapeutic potential of stem cell interventions in heart failure management.

Abstract 4136452: Acute Cardiac Function Change After Catheter Ablation of Ventricular Arrhythmias in Patients with Arrhythmogenic Right Ventricular Cardiomyopathy

Introduction: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic disorder characterized by fibrofatty replacement of myocardial tissue, creating areas of electrical heterogeneity and increasing the risk of ventricular arrhythmias (VAs) and sudden cardiac death (SCD). Catheter ablation is commonly performed in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) for management of ventricular arrhythmias (VAs). Whether catheter ablation affects cardiac function post-procedurally is uncertain. Research Question: Does catheter ablation for ARVC result in acute change in cardiac function? Goals/Aims: To assess the impact of catheter ablation for VAs on cardiac function in the acute post-procedure setting. Methods: This retrospective study included patients with ARVC who underwent catheter ablation for VAs at Mayo Clinic. Cardiac function was assessed on pre- and post-procedure transthoracic echocardiograms (TTEs). Post-procedure TTEs were obtained within 4 weeks after the ablation procedure. Right ventricular (RV) enlargement and systolic dysfunction were evaluated as continuous variables (0=none, 1=mild, 2=mild-moderate, 3=moderate, 4=moderate-severe, 5=severe). Results: The study included 32 patients who underwent a total of 44 ablations. Mean age at the time of ablation was 49±16 years, and 24 (75%) were male. After a mean follow-up duration of 2.6±5.5 days, there was a significant worsening in mean RV dysfunction (1.6±1.5 to 2.0±1.4, P = 0.001). There were no significant changes in mean left ventricular ejection fraction (LVEF), left ventricular (LV) dimensions, and RV size. 6 (14%) patients had a &gt;5% decline in LVEF, and 14 (32%) patients had worsening RV function. Transient inotropic support was required in 4 (9%) patients. Conclusion(s): This study is the first to assess the acute impact of catheter ablation for VAs on cardiac function in ARVC patients. These results underscore the importance of careful post-procedure monitoring and planning of the ablation target in these patients to avoid excessive ablation and therefore impairment in cardiac function.

Abstract 4123631: Significance of collagen triple helix repeat-containing protein 1 as a right ventricular biomarker in pulmonary hypertension

Background: Right ventricular failure is a major prognostic determinant of pulmonary hypertension and progresses with myocardial fibrosis. Extracellular matrix proteins play a major role in myocardial fibrosis. Right ventricular biomarkers for right ventricular function and fibrosis are poorly examined in pulmonary hypertension. This study investigated the significance of collagen triple helix repeat-containing protein 1 (CTHRC1), one of the extracellular matrix proteins, as a right ventricular biomarker. Methods and Results: A monocrotaline-induced pulmonary hypertension rat model was used in this study. CTHRC1 expression in the right ventricle was higher in rats with monocrotaline-induced pulmonary hypertension than in controls. CTHRC1 was associated with fibrosis in the rat's right ventricle. Next, human circulating CTHRC1 levels were evaluated in controls (n = 20), pulmonary arterial hypertension (PAH, n = 46), and chronic thromboembolic pulmonary hypertension (CTEPH) patients (n = 64). Human circulating CTHRC1 levels were higher in PAH (P = 0.006) and CTEPH patients (P = 0.011) than in controls (Figure). Human circulating CTHRC levels were correlated with tricuspid lateral annular peak systolic velocity (R = -0.213, P = 0.029), right ventricular fractional area change (R = -0.225, P = 0.017), and right ventricular global longitudinal strain evaluated by magnetic resonance imaging (R = 0.429, P = 0.009). In addition, human circulating CTHRC1 levels were decreased after balloon pulmonary angioplasty (P &lt; 0.001) in CTEPH patients. Conclusions: CTHRC1 could be a novel biomarker associated with right ventricular failure and fibrosis in pulmonary hypertension patients.

Abstract 4118444: Right Ventricular Contractile Reserve and Right Ventricular-Pulmonary Arterial Coupling Are Impaired in Long-Term Survivors of Childhood Cancers

Background: Childhood cancer survivors are at risk of right ventricular (RV) dysfunction in relation to cardiac toxicity due to chemotherapy and radiation therapy. This study tested the hypothesis that RV contractile reserve and RV-pulmonary arterial (PA) coupling are altered in long-term survivors of childhood cancers. Methods: Thirty survivors (60% men) aged 24.3 ± 5.2 years at 15.3 ± 6.3 years after completion of chemotherapy and thirty healthy control subjects (47% men) were studied. Resting and submaximal supine bicycle stress echocardiography was performed for assessment of RV fractional area change (FAC), tricuspid annular plane systolic excursion (TAPSE), left ventricular (LV) and RV longitudinal strain, mitral and tricuspid annular velocities and myocardial acceleration during isovolumic contraction (IVA). The slope of the RV force-frequency relationship was derived from the change in IVA with the change in heart rate during exercise (△IVA/△heart rate), while RV-PA coupling was determined by the ratio between TAPSE and pulmonary arterial acceleration time indexed to RV ejection time (PAATi). Results: At rest, tricuspid annular systolic velocity and RV systolic strain were significantly lower in survivors ( P &lt; 0.05 for both), while RV FAC, TAPSE and IVA were similar between the two groups ( P &gt; 0.05 for all). During submaximal exercise testing, all RV systolic functional indices were significantly lower in survivors than controls ( P &lt; 0.05 for all). The slope of the RV force-frequency relationship was significantly flatter in survivors compared to controls (0.038 ± 0.002 vs 0.059 ± 0.003 m/sec 2 beats/min, P &lt; 0.001). For RV-PA coupling, TAPSE/PAATi was similar between survivors and controls at baseline but became significantly lower in survivors during submaximal exercise ( P = 0.002). Conclusions: The RV contractile reserve and RV-PA coupling are impaired during exercise in long-term survivors of childhood cancers. Future studies aimed at determining the clinical and prognostic significance of these impairments are warranted.

Abstract 4143242: Right Ventricular Remodeling During the First Decade After Tetralogy of Fallot Repair: An Echocardiographic Study

Background: After TOF repair (TOFr), pulmonary regurgitation resulting in right ventricular (RV) dilatation and dysfunction is common. We have previously demonstrated that RV function (RVF) improves in the first two years after TOFr, however RV changes in the first decade after TOFr are less known. We investigated RVF and RV size (termed remodeling) using echocardiography during the first decade after TOFr. Methods: Retrospective cohort study of patients who underwent TOFr and were followed at our institution from 3/2012 to 12/2023. Those with at least two echocardiograms separated by one year were included. Two patients that received a pulmonary valve replacement were excluded. After confirming intra- and inter-reader reproducibility, RV remodeling was assessed offline by global longitudinal strain (GLS), free wall strain (FWS), fractional area change (FAC), end systolic area (ESA/BSA) and end diastolic area (EDA/BSA). RVF changes over time were assessed with multivariable linear mixed effects models adjusting for perioperative covariates. Two years after TOFr (Y2) was used as reference given RVF peaks at this point following surgery. Results: Out of 758 echocardiograms from 116 patients, 688 were suitable for analysis. Median age at TOFr was 3.5 months (IQR:1.92, 4.89). Compared to Y2, we identified the largest decline in RVF at Year 3, with no worsening from year to year until Y10. There were no associations of perioperative covariates with RVF except for ventriculotomy (FAC) and residual pulmonary stenosis (FWS). There was no progression in RV remodeling over the first decade after TOFr. (Graph, table). Conclusion: After the initial 2-year improvement following TOFr, RVF worsens but remains stable throughout the first decade with stable RV size accounting for BSA. Our findings augment the knowledge of RV remodeling during childhood and could help guide outpatient follow up, counseling, frequency of echocardiograms, and timing of the first cardiac MR.

Short-term outcome after isolated tricuspid valve surgery: prognostic role of right ventricular strain.

To assess the incremental prognostic value of right ventricular free wall longitudinal strain over conventional risk scores in predicting the peri-operative mortality in patients with severe tricuspid regurgitation (TR) undergoing isolated tricuspid valve (TV) surgery. We retrospectively enrolled 110 consecutive patients with severe TR who underwent isolated TV surgery between November 2016 and July 2022 at San Raffaele Hospital, Milan, Italy. Exclusion criteria were previous TV surgery, urgent surgery, complex congenital heart disease, active endocarditis and inadequate acoustic window. Baseline clinical data were included, as well as laboratory tests and clinical risk score, as TRI-SCORE and MELD-XI. The clinical outcome was peri-operative mortality, defined as all-cause mortality within 30 days. The final cohort included 79 patients. The endpoint occurred in 7 patients (9%), who died within 30-days after isolated TV surgery. ROC curves analysis showed that, among parameters of right ventricular function, right ventricular free wall longitudinal strain was the best parameter to predict peri-operative mortality (AUC: 0.854, 95% CI 0.74-0.96, p = 0.005, sensitivity 68%, specificity 100%) At univariable analysis, left ventricular ejection fraction, diabetes mellitus, creatinine, estimated glomerular filtration rate, serum sodium, MELD-XI, TRI-SCORE, right ventricular areas, right ventricular global longitudinal strain, right ventricular free wall longitudinal strain, fractional area change and the ratio between right ventricular free wall longitudinal strain/pulmonary arterial systolic pressure were significantly associated with the endpoint. The combination of TRI-SCORE and right ventricular Strain, evaluating right ventricular systolic function with speckle-tracking echocardiography, outperformed classic TRI-SCORE in outcome prediction (AUC 0.874 vs 0,787, p value=0.05). Right ventricular free wall longitudinal strain has an incremental prognostic value over conventional parameters and significantly improves the ability of clinical scores to predict peri-operative mortality in patients undergoing isolated TV surgery.

Meta-analysis of the efficacy and impact on cardiac function of sodium-glucose cotransporter 2 inhibitor Empagliflozin in heart failure patients.

Currently, there is no comprehensive systematic review available to comprehensively assess the efficacy and safety of Empagliflozin and other sodium-glucose cotransporter 2 inhibitors in the treatment of heart failure (HF). This study employed a meta-analysis approach to systematically evaluate the therapeutic effects of Empagliflozin in HF patients and its impact on cardiac function. The keywords including "heart failure," "HF," "cardiac failure," "cardiac disease," "Empagliflozin," and "sodium-glucose cotransporter 2 inhibitors" were utilized to search for relevant clinical studies on Empagliflozin in the treatment of HF in various databases, such as China National Knowledge Infrastructure, Wanfang, VIP Chinese Medical Journal Database, PubMed, MEDLINE, Embase, Cochrane Library, Springer, and Science Direct. The studies included patients with HF who received drug treatment. Data on baseline characteristics and posttreatment outcomes, including HF hospitalization (HHF), cardiovascular mortality, all-cause mortality, estimated glomerular filtration rate changes, Kansas City Cardiomyopathy Questionnaire quality of life (QoL) scores, N-terminal pro-B-type natriuretic peptide, left ventricular ejection fraction, hematocrit, and other relevant indicators were collected. Meta-analysis was conducted using RevMan5.3 to analyze the extracted data. A total of 15 studies were included in the final analysis, comprising 36,917 patients with HF. Among them, 18,486 patients were in Empagliflozin group, and 18,431 patients were in control (Ctrl) group. The results of the meta-analysis demonstrated that, relative to Ctrl group, Empagliflozin group showed a substantially lower HHF rate, a substantial improvement in estimated glomerular filtration rate changes, a reduced cardiovascular mortality rate, a higher Kansas City Cardiomyopathy Questionnaire QoL score, increased hematocrit values, reduced N-terminal pro-B-type natriuretic peptide changes, and enhanced left ventricular ejection fraction changes. These findings suggest that remarkable improvements in various outcomes compared to the Ctrl group. The sodium-glucose cotransporter 2 inhibitor Empagliflozin markedly reduces the HHF rate and cardiovascular mortality in HF patients. It also improves patients' QoL, enhances renal function, and increases cardiac function while reducing both, the preload and afterload.

Deformation-fractional change in resistance model of SMA fiber reinforced mortar beams

Superelastic shape memory alloys (SMA) are metallic alloys that can enable components with self-recovery of cracks and deformation when combined with cement-based materials. Meanwhile, the monitoring method based on fractional change in resistance (FCR) can achieve self-monitoring of components throughout the entire loading process. In this study, the relationship between crack recovery characteristics and FCR of SMA fiber reinforced mortar beams subjected to flexural cyclic loading was analyzed. The beams with SMA fiber volume fractions of 0.1 %, 0.3 %, 0.5 %, and 1.0 % were tested under three-point bending loads. During the loading process, the FCR of the specimens were monitored by the four-electrode method. Finally, the deformation-FCR model for the whole process of the specimens was established to realize the real-time monitoring of the loading state of mortar beams. The results show that SMA fibers can enhance the flexural strength of mortar beams by a maximum of about 64 %, reduce residual deformation, and improve deformation self-recovery ability. The mid-span deflection recovery rate and crack size recovery rate generally increase with higher fiber volume fraction, which can maintain a better deformation recovery effect at the early stage of cracking and gradually decrease with the expansion of cracks. There is a close relationship between the FCR and the degree of crack development that the FCR increases with crack expansion and the magnitude of FCR decreases with increasing fiber content. The established first-order logarithmic fitting model can well describe the relationship between the FCR and cracking, which can provide reference for crack monitoring.

Determinants of rhizospheric organic carbon fractions and accumulation in four different vegetations of coastal saline-alkali soils

Rhizosphere processes are key pathways through which plants influence the carbon cycling of diverse ecosystems and are closely associated with vegetation types. However, the environmental responses of rhizospheric soil organic carbon (SOC) mediated by the interaction between rhizospheric effect and vegetation type remain uncertain, severely limiting our assessment of the carbon sequestration potential of different coastal vegetation. Here, we identified the core factors driving changes in various soil carbon fractions in the rhizosphere of four coastal vegetation types by testing the contents of the reactive, dissolved, particulate, mineral-associated, heavy and light fractions of SOC and their relationships with physicochemical properties and enzyme activities. It was found that the rhizosphere effect significantly influenced SOC, with rhizospheric SOC contents varying significantly among vegetation types, ranging from 2.12 to 9.04 g/kg. Besides, rhizospheric soil pH was found to contribute significantly to SOC fractions (except for light organic carbon) and exert significant inhibitory effects on SOC, reactive organic carbon, mineral-associated organic carbon and heavy organic carbon. Despite the different responses of various SOC fractions to physicochemical properties and enzyme activities, soil available phosphorus and alkaline phosphatase activity emerged as core environmental factors influencing rhizospheric SOC accumulation across different coastal vegetation types. This study presents a promising framework for understanding the determinants of SOC fractions in rhizospheric soil, and their accumulation in the vegetation of coastal saline-alkali soils. In addition to alkalinity, phosphorus acquisition capacity can be a key predictor of coastal SOC fractions and their accumulation.

Changes in Supraspinatus Muscle Volume and Fat Fraction After Arthroscopic Rotator Cuff Repair at Minimum Follow-up of 5 Years

Changes in Supraspinatus Muscle Volume and Fat Fraction After Arthroscopic Rotator Cuff Repair at Minimum Follow-up of 5 Years

Link between permanent shear-banding and local concentration fluctuations in suspensions of compressible microgels

We uncover the occurrence of shear banding in dense suspensions of compressible microgels. Velocimetry measurements evidence the presence of permanent but unsteady shear-banding for sufficiently small Peclet numbers, with the formation of a central plug-like flow. Small-angle neutron scattering experiments under shear link the observed banding phenomenon to structural variations along the velocity gradient, providing a connection between the arrested band and the increase in structural correlations associated with changes in the local packing fraction. This provides unique evidence of a shear–concentration coupling mechanism in jammed suspensions of compressible particles.