Extracellular Fluid Research Articles

Extracellular volume-based scoring system for tracking tumor progression in pancreatic cancer patients receiving intraoperative radiotherapy

ObjectivesTo investigate the value of extracellular volume (ECV) derived from portal-venous phase (PVP) in predicting prognosis in locally advanced pancreatic cancer (LAPC) patients receiving intraoperative radiotherapy (IORT) with initial stable disease (SD) and to construct a risk-scoring system based on ECV and clinical-radiological features.Materials and methodsOne hundred and three patients with LAPC who received IORT demonstrating SD were enrolled and underwent multiphasic contrast-enhanced CT (CECT) before and after IORT. ECV maps were generated from unenhanced and PVP CT images. Clinical and CT imaging features were analyzed. The independent predictors of progression-free survival (PFS) determined by multivariate Cox regression model were used to construct the risk-scoring system. Time-dependent receiver operating characteristic (ROC) curve analysis and the Kaplan–Meier method were used to evaluate the predictive performance of the scoring system.ResultsMultivariable analysis revealed that ECV, rim-enhancement, peripancreatic fat infiltration, and carbohydrate antigen 19-9 (CA19-9) response were significant predictors of PFS (all p < 0.05). Time-dependent ROC of the risk-scoring system showed a satisfactory predictive performance for disease progression with area under the curve (AUC) all above 0.70. High-risk patients (risk score ≥ 2) progress significantly faster than low-risk patients (risk score < 2) (p < 0.001).ConclusionECV derived from PVP of conventional CECT was an independent predictor for progression in LAPC patients assessed as SD after IORT. The scoring system integrating ECV, radiological features, and CA19-9 response can be used as a practical tool for stratifying prognosis in these patients, assisting clinicians in developing an appropriate treatment approach.Critical relevance statementThe scoring system integrating ECV fraction, radiological features, and CA19-9 response can track tumor progression in patients with LAPC receiving IORT, aiding clinicians in choosing individual treatment strategies and improving their prognosis.Key PointsPredicting the progression of LAPC in patients receiving IORT is important.Our ECV-based scoring system can risk stratifying patients with initial SD.Appropriate prognostication can assist clinicians in developing appropriate treatment approaches.Graphical

Impact of tafamidis on myocardial function and CMR tissue characteristics in transthyretin amyloid cardiomyopathy.

Tafamidis improves clinical outcomes in transthyretin amyloid cardiomyopathy (ATTR-CM), yet how tafamidis affects cardiac structure and function remains poorly described. This study prospectively analysed the effect of tafamidis on 12-month longitudinal changes in cardiac structure and function by cardiac magnetic resonance (CMR) compared with the natural course of disease in an untreated historic control cohort. ATTR-CM patients underwent CMR at tafamidis initiation and at 12months. Untreated patients with serial CMRs served as reference to compare biventricular function, global longitudinal strain (GLS), LV mass and extracellular volume fraction (ECV). Thirty-six tafamidis-treated (n=35; 97.1% male) and 15 untreated patients (n=14; 93.3% male) with a mean age of 78.3±6.5 and 76.9±6.5, respectively, and comparable baseline characteristics were included. Tafamidis was associated with preserving biventricular function (LVEF (%): 50.5±12 to 50.7±11.5, P=0.87; RVEF (%): 48.2±10.4 to 48.2±9.4, P=0.99) and LV-GLS (-9.6±3.2 to -9.9±2.4%; P=0.595) at 12months, while a significantly reduced RV-function (50.8±7.3 to 44.2±11.6%, P=0.028; P (change over time between groups)=0.032) and numerically worsening LVGLS (-10.9±3.3 to -9.1±2.9%, P=0.097; P (change over time between groups)=0.048) was observed without treatment. LV mass significantly declined with tafamidis (184.7±47.7 to 176.5±44.3g; P=0.011), yet remained unchanged in untreated patients (163.8±47.5 to 171.2±39.7g P=0.356, P (change over time between groups)=0.027). Irrespective of tafamidis, ECV and native T1-mapping did not change significantly from baseline to 12-month follow-up (P>0.05). Compared with untreated ATTR-CM patients, initiation of tafamidis preserved CMR-measured biventricular function and reduced LV mass at 12months. ECV and native T1-mapping did not change significantly comparable to baseline in both groups.

Analysis of the Interaction Effects of Electromagnetic Fields with Major Living Tissues—One Health Concept Numerical Evaluation Strategy

The well-being and sociability of individuals have always been part of modernity. The development of new technologies that meet these aspirations is receiving increasing attention. Thus, strengthening the desired objectives of these technologies and minimizing their undesirable side effects is the subject of growing commitment. The present contribution aims, in this context, to evaluate and analyze the desired and undesirable effects of the interaction of electromagnetic fields with living tissues in general. These are routines based on mathematical modeling reinforcing the expected functions as well as those of control and protection against undesirable effects. These adverse effects correspond to the “One Health” concept, which encompasses the health of animals, plants and humans, as well as ecological disorders created by human activity. First, in this article, the interactions of electromagnetic fields with tissues are analyzed, involving their thermal biological effects of desired and undesired exposures. The roles of blood and sap fluids in bio-affected tissues are then analyzed. Secondly, the equations governing electromagnetics and bio-heat, as well as their coupled solution are studied. Third, the thermal behavior of tissues and the adverse effects of exposure are examined. Next, monitoring and defending the effects of exposures are discussed. This contribution, supported by a review of the literature, illustrates routines for mathematical modeling of the generalized interaction of electromagnetic fields with living tissues.

Disturbance in the protein landscape of cochlear perilymph in an Alzheimer's disease mouse model.

Hearing loss is a pivotal risk factor for dementia. It has recently emerged that a disruption in the intercommunication between the cochlea and brain is a key process in the initiation and progression of this disease. However, whether the cochlear properties can be influenced by pathological signals associated with dementia remains unclear. In this study, using a mouse model of Alzheimer's disease (AD), we investigated the impacts of the AD-like amyloid β (Aβ) pathology in the brain on the cochlea. Despite little detectable change in the age-related shift of the hearing threshold, we observed quantitative and qualitative alterations in the protein profile in perilymph, an extracellular fluid that fills the path of sound waves in the cochlea. Our findings highlight the potential contribution of Aβ pathology in the brain to the disturbance of cochlear homeostasis.

Evaluation of Change in Body Composition, including Phase Angle, in Post-Myocardial Infarction Patients Rehabilitated under the KOS-Zawał (MC-AMI) Programme

Background: Ischaemic heart disease, including myocardial infarction, is one of the main causes leading to heart failure as a consequence of ischaemic myocardial damage. In recent years, survival in the acute phase of myocardial infarction has improved significantly, but the high mortality rate within 12 months of hospital discharge (reaching up to 9.8% in Poland) remains a challenge. Therefore, the KOS-Zawał (MC-AMI) comprehensive 12-month post-MI care programme was introduced in Poland in 2017. Aim: This study aimed to assess body composition (including, but not limited to, the phase angle, visceral fat, total body fat, redistribution between intracellular and extracellular fluid in the body, and metabolic age) using a bioelectrical impedance analysis (BIA) in post-MI patients before and after early post-MI rehabilitation who were participating in the KOS-Zawał (MC-AMI) programme. Methods: This study involved an examination (before rehabilitation) of 94 post-myocardial infarction patients who were referred to a cardiology appointment within 7–10 days of hospital discharge, during which a clinical assessment, electrocardiogram, and biochemical blood tests (complete blood count, CRP, and serum creatinine) were performed. For various reasons (death, qualification for device implantation, non-completion of rehabilitation, failure to attend a follow-up BIA), data from 55 patients who were examined twice (before and after rehabilitation) were used for the final analysis. Measurements were taken using a high-grade Tanita MC-780 BIA body composition analyser, which measured the resistance of tissues to a low-intensity electrical impulse (not perceptible to the subject). Results: Participation in rehabilitation as part of the KOS-Zawał (MC-AMI) programme was associated with a decrease in metabolic age in patients, with a reduction in visceral fat levels and levels of adipose tissue in the lower and upper limbs. Moreover, a clinically beneficial reduction in the ratio of extracellular water to total body water was also observed. These changes were statistically significant (p &lt; 0.005). In contrast, there were no statistically significant differences in the change in phase angle values in the subjects before and after the 5-week post-infarction rehabilitation. Conclusions: Participation in early post-myocardial infarction rehabilitation as part of the KOS-Zawał (MC-AMI) programme (25 training sessions) is associated with significant improvements in body composition parameters, such as visceral adipose tissue, limb fat, and water redistribution, and, consequently, a reduction in metabolic age, despite no significant increase in phase angle values. It was hypothesised that the good baseline condition of the subjects might explain the lack of significant change in the phase angle over the short observation period. For further analysis, it would be worthwhile to increase the number of patients with baseline reduced phase angle values and monitor changes in this parameter throughout rehabilitation and the entire MC-AMI programme, because changes in the phase angle may also be influenced by other programme components such as dietary or psychological education. It is worth considering implementing a regular BIA assessment in patients in the programme as a motivating stimulus for diligent exercise and extending rehabilitation to be followed by telerehabilitation or hybrid telerehabilitation.

Varicose vein treatment reduces edema not only in the treated legs but also in the entire body.

We explored the connection between varicose vein and edema, by investigating extracellular water ratio (E/T) using bioelectrical impedance analysis. In a prospective cohort study 120 patients underwent varicose vein surgery with extracellular fluid to total body water ratio (E/T) and E/T postop divided by E/Tpreop (E/T ratio) measured using a body composition analyzer. Edema was defined as E/T ≥0.390. Seventy-nine patients received unilateral treatment, while 41 underwent bilateral. p < .05 is statistically significant. Preoperatively, patients exhibited edema (E/T) in the treated leg (0.394 ± 0.009), untreated leg (0.392 ± 0.009), trunk (0.390 ± 0.007), and whole body (0.391 ± 0.007). Postoperatively, E/T decreased across body (p < .05). The lowest E/T ratio was observed in the treated leg (0.991 ± 0.012), followed by the untreated leg (0.994 ± 0.012), the trunk (0.995 ± 0.009), and the whole body (0.994 ± 0.009). E/T ratio of bilateral group were lower than unilateral group (p < .05). Varicose vein contributes to generalized edema, and treatment alleviates edema in the treated leg and the entire body.

Injectable Thermosensitive Gel CH-BPNs-NBP for Effective Periodontitis Treatment through ROS-Scavenging and Jaw Vascular Unit Protection.

Periodontitis, a prevalent inflammatory condition in the oral cavity, is closely associated with oxidative stress-induced tissue damage mediated by excessive reactive oxygen species (ROS) production. The jaw vascular unit (JVU), encompassing both vascular and lymphatic vessels, plays a crucial role in maintaining tissue fluid homeostasis and contributes to the pathological process in inflammatory diseases of the jaw. In this study, we present a novel approach for treating periodontitis through the development of an injectable thermosensitive gel (CH-BPNs-NBP). The gel formulation incorporated black phosphorus nanosheets (BPNs), which are notable for their ROS-scavenging properties, and dl-3-n-butylphthalide (NBP), a vasodilator that promotes lymphatic vessel function within the JVU. Our results demonstrated that the designed thermosensitive gel served as a controlled release system, delivering BPNs and NBP to the site of inflammation. CH-BPNs-NBP not only protected macrophages and human lymphatic endothelial cells from ROS attack but also promoted M2 polarization and lymphatic function. In in vivo studies, we observed a significant reduction in inflammation and tissue damage, accompanied by a notable promotion of alveolar bone regeneration. This research introduces a promising therapeutic strategy for periodontitis, leveraging the unique properties of BPNs and NBP within an injectable thermosensitive gel. This article is protected by copyright. All rights reserved.

Does PAD and microcirculation status impact the tissue availability of intravenously administered antibiotics in patients with infected diabetic foot? Results of the DFIATIM substudy

Aims/hypothesisThe aim of this substudy (Eudra CT No:2019-001997-27)was to assess ATB availability in patients with infected diabetic foot ulcers(IDFUs)in the context of microcirculation and macrocirculation status.MethodsFor this substudy, we enrolled 23 patients with IDFU. Patients were treated with boluses of amoxicillin/clavulanic acid(AMC)(12patients) or ceftazidime(CTZ)(11patients). After induction of a steady ATB state, microdialysis was performed near the IDFU. Tissue fluid samples from the foot and blood samples from peripheral blood were taken within 6 hours. ATB potential efficacy was assessed by evaluating the maximum serum and tissue ATB concentrations(Cmax and Cmax-tissue)and the percentage of time the unbound drug tissue concentration exceeds the minimum inhibitory concentration (MIC)(≥100% tissue and ≥50%/60% tissue fT&amp;gt;MIC). Vascular status was assessed by triplex ultrasound, ankle–brachial and toe–brachial index tests, occlusive plethysmography comprising two arterial flow phases, and transcutaneous oxygen pressure(TcPO2).ResultsFollowing bolus administration, the Cmax of AMC was 91.8 ± 52.5 μgmL-1 and the Cmax-tissue of AMC was 7.25 ± 4.5 μgmL-1(P&amp;lt;0.001). The Cmax for CTZ was 186.8 ± 44.1 μgmL-1 and the Cmax-tissue of CTZ was 18.6 ± 7.4 μgmL-1(P&amp;lt;0.0001). Additionally, 67% of patients treated with AMC and 55% of those treated with CTZ achieved tissue fT&amp;gt;MIC levels exceeding 50% and 60%, respectively. We observed positive correlations between both Cmax-tissue and AUCtissue and arterial flow. Specifically, the correlation coefficient for the first phase was r=0.42; (P=0.045), and for the second phase, it was r=0.55(P=0.01)and r=0.5(P=0.021).ConclusionsBactericidal activity proved satisfactory in only half to two-thirds of patients with IDFUs, an outcome that appears to correlate primarily with arterial flow.

Interpretable machine learning based on CT-derived extracellular volume fraction to predict pathological grading of hepatocellular carcinoma.

To develop a non-invasive auxiliary assessment method based on CT-derived extracellular volume (ECV) to predict the pathological grading (PG) of hepatocellular carcinoma (HCC). The study retrospectively analyzed 238 patients who underwent HCC resection surgery between January 2013 and April 2023. Six machine learning algorithms were employed to construct predictive models for HCC PG: logistic regression, extreme gradient boosting, Light Gradient Boosting Machine (LightGBM), random forest, adaptive boosting, and Gaussian naive Bayes. Model performance was evaluated using receiver operating characteristic curve analysis, including area under the curve (AUC), sensitivity, specificity, accuracy, positive predictive value, negative predictive value, and F1 score. Calibration plots were used for visual evaluation of model calibration. Clinical decision curve analysis was performed to assess potential clinical utility by calculating net benefit. 166 patients from Hospital A were allocated to the training set, while 72 patients from Hospital B (constituting 30.25% of the total sample) were assigned to the test set. The model achieved an AUC of 1.000 (95%CI: 1.000-1.000) in the training set and 0.927 (95%CI: 0.837-0.999) in the validation set, respectively. Ultimately, the model achieved an AUC of 0.909 (95%CI: 0.837-0.980) in the test set, with an accuracy of 0.778, sensitivity of 0.906, specificity of 0.789, negative predictive value of 0.556, and F1 score of 0.908. This study successfully developed and validated a non-invasive auxiliary assessment method based on CT-derived ECV to predict the HCC PG, providing important supplementary information for clinical decision-making.

The mechanism of mitochondrial autophagy regulating Clathrin-mediated endocytosis in epilepsy.

The objective of this study is to determine whether inhibition of mitophagy affects seizures through Clathrin-mediated endocytosis (CME). Pentylenetetrazol (PTZ) was intraperitoneally injected daily to establish a chronic PTZ-kindled seizure. The Western blot (WB) was used to compare the differences in Parkin protein expression between the epilepsy group and the control group. Immunofluorescence was used to detect the expression of MitoTracker and LysoTracker. Transferrin-Alexa488 (Tf-A488) was injected into the hippocampus of mice. We evaluated the effect of 3-methyladenine (3-MA) on epilepsy behavior through observation in PTZ-kindled models. The methylated derivative of adenine, known as 3-MA, has been extensively utilized in the field of autophagy research. The transferrin protein is internalized from the extracellular environment into the intracellular space via the CME pathway. Tf-A488 uses a fluorescent marker to track CME. Western blot showed that the expression of Parkin was significantly increased in the PTZ-kindled model (p < 0.05), while 3-MA could reduce the expression (p < 0.05). The fluorescence uptake of MitoTracker and LysoTracker was increased in the primary cultured neurons induced by magnesium-free extracellular fluid (p < 0.05); the fluorescence uptake of Tf-A488 was significantly decreased in the 3-MA group compared with the control group (p < 0.05). Following hippocampal injection of Tf-A488, both the epilepsy group and the 3-MA group exhibited decreased fluorescence uptake, with a more pronounced effect observed in the 3-MA group. Inhibition of mitophagy by 3-MA from day 3 to day 9 progressively exacerbated seizure severity and shortened latency. It is speculated that the aggravation of seizures by 3-MA may be related to the failure to remove damaged mitochondria in time and effectively after inhibiting mitochondrial autophagy, affecting the vesicle endocytosis function of CME and increasing the susceptibility to epilepsy. Abnormal mitophagy was observed in a chronic pentylenetetrazol-induced seizure model and a Mg2+-free-induced spontaneous recurrent epileptiform discharge model. A fluorescent transferrin marker was utilized to track clathrin-mediated endocytosis. Using an autophagy inhibitor (3-methyladenine) on primary cultured neurons, we discovered that inhibition of autophagy led to a reduction in fluorescent transferrin uptake, while impairing clathrin-mediated endocytosis function mediated by mitophagy. Finally, we examined the effects of 3-methyladenine in an animal model of seizures showing that it exacerbated seizure severity. Ultimately, this study provides insights into potential mechanisms through which mitophagy regulates clathrin-mediated endocytosis in epilepsy.

Abstract PO3-12-07: Utility of Volumetric Measurement for Clinical Diagnosis of Breast Cancer-Related Lymphedema

Abstract Background: Early detection of Breast cancer-related lymphedema (BCRL) is crucial since it can significantly reduce the negative impact on a patient’s quality of life after breast cancer treatment. Several objective screening methods have been used in prior studies but have not proven accurate due to a lack of standardization. Bioimpedance spectroscopy (BIS), which assesses tissue resistance to an electric current and converts it into a score to measure interstitial fluid content, has proven to be an accurate tool in diagnosing lymphedema. SOZO® is a BIS device that generates quantitative results in real time and provides a Lymphedema Index (L-Dex) score by measuring the patient's extracellular fluid volume. However, there is a paucity of literature highlighting its clinical applicability. Thus, we aimed to evaluate the clinical utility of SOZO® in diagnosing BCRL in patients undergoing breast cancer surgery. Materials &amp; Methods: A retrospective chart review was carried out of patients who underwent axillary surgery from January 2019 to December 2022. Demographic information such as age, body mass index (BMI), gender, ethnicity, disease pathology, cancer stage, type of axillary surgery, neoadjuvant and adjuvant treatment received was recorded. Patients undergoing sentinel lymph node biopsy (SLNB) and/or axillary lymph node dissection (ALND) were assessed for their preoperative L-Dex score, and they were followed up postoperatively with repeated measurements of their L-Dex score to diagnose lymphedema for a year at 3 months intervals. Clinical lymphedema was defined as those having an absolute L-Dex score of more than +10 and an increase in L-Dex score by 6.5 from the baseline. SOZO® scores measured at each follow-up were compared to their preoperative baseline scores. Results: A total of 200 patients’ data was evaluated whose mean age and BMI were 57.5+10.9 years and 29.6+5.6 kg/m2, respectively. Eighty-five percent of the patients belonged to ethnic minority groups. Furthermore, 84.5% (n=169) of the patients had SLNB, and 15.5% (n=31) had ALND. All the patients included in the study had their preoperative and postoperative quarterly L-Dex scores recorded. Pre- and post-operative L-Dex scores had a mean of -0.20+6.6 and 0.61+6.8, respectively. A total of 20 (10%) patients developed lymphedema without symptoms detected by SOZO®, with 19 (9.5%) resolving at their respective 3-month follow-up and 1 (0.5%) patient with persistent lymphedema at the end of the 24-month follow-up. All 20 patients were treated with a compression sleeve. Of the 20 patients with lymphedema, 4 patients underwent ALND, whereas 16 patients had SLNB. When compared to their preoperative baseline scores, all patients' SOZO® measurements had an absolute score of more than 10 and an increase of 6.5 from their baseline score. Additionally, 21 other patients had an increase in score of 6.5 from their baseline measurements but did not meet the cut-off range of an absolute score of +10. Therefore, we excluded them from the diagnosis of BCRL, and none of these patients later developed any signs of BCRL, such as swelling, pain, or discomfort. Conclusion: SOZO® procedure can accurately detect BCRL. In our study, 1 patient developed clinical lymphedema after undergoing SLNB and was diagnosed using SOZO®. Additionally, 19 patients who were initially diagnosed with lymphedema were later categorized as transient due to the resolution of lymphedema on follow-up. Early identification of transient lymphedema using SOZO® resulted in the prevention of a potentially life-long debilitation in our patients. Moreover, our findings underscore that an increase in SOZO® score from the baseline by &amp;gt; 6.5 with an absolute score of more than +10 should be the threshold to clinically diagnose lymphedema. Future studies with larger sample sizes and longer follow-up duration are necessary to understand better the utility of SOZO® in diagnosing BCRL. Table 1: Baseline characteristics and follow-up data of the patients included in the study. Citation Format: Fardeen Bhimani, Sheldon Feldman, Yu Chen, Anjuli Gupta, Jessica Pastoriza, Areej Shihabi, Maureen McEvoy. Utility of Volumetric Measurement for Clinical Diagnosis of Breast Cancer-Related Lymphedema [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-12-07.

Cardiac MRI for clinical dilated cardiomyopathy: Improved diagnostic power via combined T1, T2, and ECV

IntroductionEarly diagnosis of patients with dilated cardiomyopathy (DCM) remains challenging. Cardiac MR can correlate myocardial changes with their pathological basis. There have been some previous studies on the effect of T1 mapping in DCM, but there is limited data on the incremental value of T2 mapping for DCM in routine clinical practice. This study will examine whether the combination of MRI T1 and T2 mapping offers greater advantages in the diagnosis of DCM. MethodsThe study included 28 patients with DCM and 21 healthy controls. CMR evaluation included late gadolinium enhancement (LGE), T1 mapping, extracellular volume (ECV) fraction and T2 mapping. The DCM group was divided into LGE (+) and LGE (−) subgroups. The main modes of LGE are subendocardial, midwall, subepicardial, or transmural. T1 values, T2 values, and ECV in the 16 segments myocardial levels were measured by post-processing software. Student's t-tests or Mann–Whitney U test was used to compare between two groups, and one-way ANOVA or Kruskal–Wallis H test was used to compare between multiple groups, with p values corrected by Bonferroni. The difference was considered statistically significant at P < 0.05. ROC curve analysis was used to compare the area under the curve (AUC) of each index and its combined value, and the cut-off value, sensitivity and specificity were determined by Jordan's index. ResultsMean native myocardial T1, ECV and T2 were significantly higher in the DCM group compared to controls (p ≤ 0.001, respectively). The best cut-off values for T1, T2 and ECV to discriminate DCM from controls were 1184 ms, 40.9 ms and 29.2%, respectively. The AUC of T1, ECV and T2 were 0.87, 0.89, and 0.83, respectively. The combined AUC of the three values was 0.96. ConclusionNative T1 value and ECV overcome some of the limitations of LGE, and the T2 helps to understand the extent of myocardial damage. The combination of T1 and T2 mapping techniques can reveal fibrotic and oedematous changes in the early stages of DCM, providing a more comprehensive assessment of DCM and better guidance for individualised clinical management of patients. Implications for practiceWe suggest that the addition of T2 mapping to the routine CMR examination of patients with suspected DCM, and the combined assessment of T1mapping and T2 mapping can provide complementary information about the disease and improve the early diagnosis of DCM.

“Interstitial fibrosis is associated with left atrial remodeling and adverse clinical outcomes in selected low-risk patients with hypertrophic cardiomyopathy”

BackgroundCardiovascular magnetic resonance (CMR) extracellular volume (ECV) allows non-invasive detection of myocardial interstitial fibrosis, which may be related to diastolic dysfunction and left atrial (LA) remodeling in hypertrophic cardiomyopathy (HCM). While the prognostic role of LGE is well-established, interstitial fibrosis and LA dysfunction are emerging novel markers in HCM. This study aimed to explore the interaction between interstitial fibrosis by ECV, LA morpho-functional parameters and adverse clinical outcomes in selected low-risk patients with HCM. Methods115 HCM patients and 61 matched controls underwent CMR to identify: i) interstitial fibrosis by ECV in hypertrophied left ventricular LGE-negative remote myocardium (r-ECV); ii) LA indexed maximum (LAVi max) and minimum (LAVi min) volumes, ejection fraction (LA-EF) and strain (reservoir εs, conduit εe and booster εa), by CMR feature-tracking. 2D-echocardiographic assessment of diastolic function was also performed within 6 months from CMR. A composite endpoint including worsening NYHA class, heart failure hospitalization, atrial fibrillation and all-cause death was evaluated at 2.3 years follow-up. HCM patients were divided into two groups, according to r-ECV values of controls. ResultsPatients with r-ECV ≥29% (n = 45) showed larger LA volumes (LAVimax 63 vs. 54 ml/m2, p < 0.001; LAVimin 43 vs. 28 ml/m2, p 〈0001), worse LA function (εs 16 vs. 28%, εe 8 vs. 15%, εa 8 vs. 14%, LA-EF 33 vs. 49%, all p < 0.001) and elevated Nt-proBNP (1115 vs. 382 pg/ml, p = 0.002). LA functional parameters inversely correlated with r-ECV (εs r = −0.54; LA-EF r = −0.46; all p < 0.001) and E/e' (εs r = −0.52, LA-EF r = −0.46; all p < 0.006). r-ECV ≥29% and LAVi min >30 ml/m2 have been identified as possible independent factors associated with the endpoint. ConclusionsIn HCM diffuse interstitial fibrosis detected by increased r-ECV is associated with LA remodeling and emerged as a potential independent predictor of adverse clinical outcomes, on top of the well-known prognostic impact of LGE.

Assessing brain microstructural changes in chronic kidney disease: a diffusion imaging study using multiple models

ObjectivesTo explore the effectiveness of diffusion quantitative parameters derived from advanced diffusion models in detecting brain microstructural changes in patients with chronic kidney disease (CKD).MethodsThe study comprised 44 CKD patients (eGFR&amp;lt;59 mL/min/1.73 m2) and 35 age-and sex-matched healthy controls. All patients underwent diffusion spectrum imaging (DSI) and conventional magnetic resonance imaging. Reconstructed to obtain diffusion MRI models, including diffusion tensor imaging (DTI), neurite orientation dispersion and density imaging (NODDI) and Mean Apparent Propagator (MAP)-MRI, were processed to obtain multi-parameter maps. The Tract-Based Spatial Statistics (TBSS) analysis was utilized for detecting microstructural differences and Pearson correlation analysis assessed the relationship between renal metabolism markers and diffusion parameters in the brain regions of CKD patients. Receiver operating characteristic (ROC) curve analysis assessed the diagnostic performance of diffusion models, with AUC comparisons made using DeLong’s method.ResultsSignificant differences were noted in DTI, NODDI, and MAP-MRI parameters between CKD patients and controls (p &amp;lt; 0.05). DTI indicated a decrease in Fractional Anisotropy(FA) and an increase in Mean and Radial Diffusivity (MD and RD) in CKD patients. NODDI indicated decreased Intracellular and increased Extracellular Volume Fractions (ICVF and ECVF). MAP-MRI identified extensive microstructural changes, with elevated Mean Squared Displacement (MSD) and Q-space Inverse Variance (QIV) values, and reduced Non-Gaussianity (NG), Axial Non-Gaussianity (NGAx), Radial Non-Gaussianity (NGRad), Return-to-Origin Probability (RTOP), Return-to-Axis Probability (RTAP), and Return-to-Plane Probability (RTPP). There was a moderate correlation between serum uric acid (SUA) and diffusion parameters in six brain regions (p &amp;lt; 0.05). ROC analysis showed the AUC values of DTI_FA ranged from 0.70 to 0.793. MAP_NGAx in the Retrolenticular part of the internal capsule R reported a high AUC value of 0.843 (p &amp;lt; 0.05), which was not significantly different from other diffusion parameters (p &amp;gt; 0.05).ConclusionThe advanced diffusion models (DTI, NODDI, and MAP-MRI) are promising for detecting brain microstructural changes in CKD patients, offering significant insights into CKD-affected brain areas.

Mechanics of Lymphatic Pumping and Lymphatic Function.

The lymphatic system plays a crucial role in maintaining tissue fluid balance, immune surveillance, and the transport of lipids and macromolecules. Lymph is absorbed by initial lymphatics and then driven through lymph nodes and to the blood circulation by the contraction of collecting lymphatic vessels. Intraluminal valves in collecting lymphatic vessels ensure the unidirectional flow of lymph centrally. The lymphatic muscle cells that invest in collecting lymphatic vessels impart energy to propel lymph against hydrostatic pressure gradients and gravity. A variety of mechanical and biochemical stimuli modulate the contractile activity of lymphatic vessels. This review focuses on the recent advances in our understanding of the mechanisms involved in regulating and collecting lymphatic vessel pumping in normal tissues and the association between lymphatic pumping, infection, inflammatory disease states, and lymphedema.

Asymmetric Myocardial Involvement as an Early Indicator of Cardiac Dysfunction in Pediatric Dystrophinopathies: A Study on Cardiac Magnetic Resonance (CMR) Parametric Mappings.

Dystrophinopathies, such as Duchenne and Becker muscular dystrophy, frequently lead to cardiomyopathy, being its primary cause of mortality. Detecting cardiac dysfunction early is crucial, but current imaging methods lack insight into microstructural remodeling. This study aims to assess the potential of cardiac magnetic resonance (CMR) parametric mappings for early detection of myocardial involvement in dystrophinopathies and explores whether distinct involvement patterns may indicate impending dysfunction. In this prospective study, 23 dystrophinopathy patients underwent CMR with tissue mappings. To establish a basis for comparison, a control group of 173 subjects was analyzed. CMR protocols included SSFP, T2-weighted and T1-weighted sequences pre and post gadolinium, and tissue mappings for native T1 (nT1), extracellular volume (ECV), and T2 relaxation times. The difference between the left ventricular posterior wall and the interventricular septum was calculated to reveal asymmetric myocardial involvement. Significant differences in LV ejection fraction (LVEF), myocardial mass, and late gadolinium enhancement confirmed abnormalities in patients. Tissue mappings: nT1 (p < 0.001) and ECV (p = 0.002), but not T2, displayed substantial variations, suggesting sensitivity to myocardial involvement. Asymmetric myocardial involvement in nT1 (p = 0.01) and ECV (p = 0.012) between septal and LV posterior wall regions was significant. While higher mapping values didn't correlate with dysfunction, asymmetric involvement in nT1 (ρ=-0.472, p = 0.023) and ECV (ρ=-0.460, p = 0.049) exhibited a significant negative correlation with LVEF. CMR mappings show promise in early myocardial damage detection in dystrophinopathies. Although mapping values may not directly correspond to dysfunction, the negative correlation between asymmetric involvement in nT1 and ECV with LVEF suggests their potential as early biomarkers. Larger, longitudinal studies are needed for a comprehensive understanding and improved risk stratification in dystrophinopathies.

Cardiorenal Syndromes and Their Role in Water and Sodium Homeostasis

Sodium is the main osmotically active ion in the extracellular fluid and its concentration goes hand in hand with fluid volume. Under physiological conditions, homeostasis of sodium and thus amount of fluid is regulated by neural and humoral interconnection of body tissues and organs. Both heart and kidneys are crucial in maintaining volume status. Proper kidney function is necessary to excrete regulated amount of water and solutes and adequate heart function is inevitable to sustain renal perfusion pressure, oxygen supply etc. As these organs are bidirectionally interconnected, injury of one leads to dysfunction of another. This condition is known as cardiorenal syndrome. It is divided into five subtypes regarding timeframe and pathophysiology of the onset. Hemodynamic effects include congestion, decreased cardiac output, but also production of natriuretic peptides. Renal congestion and hypoperfusion leads to kidney injury and maladaptive activation of renin-angiotensin-aldosterone system and sympathetic nervous system. In cardiorenal syndromes sodium and water excretion is impaired leading to volume overload and far-reaching negative consequences, including higher morbidity and mortality of these patients. Keywords: Cardiorenal syndrome • Renocardiac syndrome • Volume overload • Sodium retention

Single-Stage Endoscopic Repair of Pediatric Basal Encephalocele: A Comprehensive Multimedia Case Report.

Basal encephaloceles are the result of a concomitant cranial and dural defect that allows for inferior displacement of cerebral tissue, meninges, and cerebrospinal fluid into the paranasal sinuses and outside the cranial vault. This work illustrates a step-by-step surgical approach of a successful single-stage, endoscopic repair of a congenital basal encephalocele in a 10-year-old child, using a free mucosal middle turbinate graft that provided effective results without utilization of traditional open reconstructive techniques or vascularized flaps. A previously healthy 10-year-old male with a history of unilateral clear rhinorrhea was admitted as an inpatient because of an acute episode of nausea, vomiting, and confusion, accompanied by fever, diplopia, and bilateral abducens nerve palsies. Preoperative imaging revealed a 2-cm right-sided intranasal mass accompanied by a subcentimeter skull base defect spanning the lateral lamella. After completing a course of intravenous antibiotic therapy for 1 week after a negative lumbar puncture to ensure clearance of intracranial infection, the decision was made to proceed with definitive endoscopic skull base repair to obviate recurrent bacterial meningitis episodes and potential neurological complications. This study demonstrates technical feasibility of a single-stage endoscopic endonasal approach for pediatric basal encephalocele resection and repair which minimizes craniofacial morbidity associated with traditional open approaches and sinonasal morbidity associated with local pedicle-based flaps for small cranial base defects in this unique patient population.

Development of rabbit models of ventilator-associated bacterial pneumonia produced by carbapenem-resistant Pseudomonas aeruginosa.

Ventilator-associated bacterial pneumonia (VABP) is among the most intractable of carbapenem-resistant Gram-negative bacterial infections. New antimicrobial agents are critically needed for the treatment of VABP. However, current conventionally used animal model systems are inadequate to meet this challenge. We, therefore, developed rabbit models of VABP caused by carbapenem-resistant Pseudomonas aeruginosa. Persistently neutropenic New Zealand White rabbits were used throughout the study. The early-phase intubated model (0-24 h) received mechanical ventilation, while the late-phase intubated model (72-96 h) was ambulatory. The following outcome parameters were studied: survival, residual tissue bacterial burden (CFU/g), residual BAL bacterial burden (CFU/mL), lung weights, pulmonary lesion score, histology, O2 saturation, radiographic imaging, and histology. Each anesthetized rabbit received a predetermined endotracheal bacterial inoculum, and ventilators were set to FiO2 = 40% and PEEP = 8 mmHg. Within the first 12 h post-inoculation, mean bacterial burdens in lung tissue and BAL fluid, respectively, were established at approximately 107 CFU/g and 106 CFU/mL, persisted through 24 h in the early-phase model and increased in the late-phase model to approximately 108 CFU/g and 107 CFU/mL. Mean max SpO2 was ≥98 mmHg, and mean nadir SpO2 was ≥68 mmHg. Serial thoracic radiographs demonstrated progressive multilobar pneumonic infiltrates. Lung histology revealed progressive focal bronchopneumonia, coagulative necrosis, intra-alveolar hemorrhage, alveolar epithelial cell necrosis, and bacterial microcolonies. The new rabbit model of VABP produced by carbapenem-resistant Pseudomonas aeruginosa recapitulates the pathophysiological, microbiological, diagnostic imaging, and histological patterns of human disease by which to assess critically needed new antimicrobial agents against this lethal infection.

Clinical characteristics of patients with high extracellular volume fraction evaluated by cardiac computed tomography for coronary artery evaluation

Abstract Aim To evaluate the distribution of extracellular volume fraction detected via computed tomography, clinical characteristics of high extracellular volume fraction detected via computed tomography, and the rate of incidental detection of cardiac amyloidosis in patients undergoing cardiac computed tomography for coronary artery evaluation. Methods and Results This study included 874 consecutive patients (mean age, 74.4 ± 7.1 years; men, 65%), comprising men aged ≥60 years and women aged ≥70 years, who had undergone cardiac computed tomography between January 2020 and September 2022. The mean extracellular volume fraction detected via computed tomography was 29.7 ± 5.2%, and 108 patients (12.4%) had an extracellular volume fraction detected via computed tomography of ≥35%. Older age (75.9 ± 8.2 years vs. 74.2 ± 6.9 years; P = 0.042), male sex (75.9% vs. 63.0%; P = 0.007), impaired left ventricular ejection fraction, increased high-sensitivity cardiac troponin T and B-type natriuretic peptide levels, and increased left ventricular thickness showed significant associations with an extracellular volume fraction detected via computed tomography of ≥35%. Cardiac amyloidosis was diagnosed incidentally in 15 patients based on an increase in extracellular volume fraction detected via computed tomography. The prevalence of cardiac amyloidosis was 1.7% (15/874) and 14.3% (15/105) in the entire study population and in patients with an extracellular volume fraction detected via computed tomography of ≥35%, respectively. An increase in the extracellular volume fraction detected via computed tomography was suggestive of cardiac amyloidosis. Conclusion Elevated extracellular volume fraction detected via computed tomography, associated with elevated cardiac biomarker levels and myocardial structural changes, may lead to the incidental diagnosis of cardiac amyloidosis.