Adult Ventricle Research Articles

Effect of obesity and hypertension on left ventricular geometry and function among asymptomatic Indian adults.

Hypertension & obesity are important independent predictors of cardiovascular morbidity & mortality specifically left ventricular (LV) functions. With the Objectives to examine the effect of obesity & hypertension on echocardiographic parameters of geometry, systolic, and diastolic functions of left ventricle in asymptomatic adults the cross-sectional study was conducted with 100 individuals (60 male & 40 female). Their Blood Pressure & Body Mass Index was recorded following which they were divided into obese normotensives & non-obese hypertensive. Echocardiographic parameters indicating LV geometry and function were recorded. Data was statistically analysed with Unpaired t test considering p value <0.05 as significant. LV geometry and LV systolic function parameters were significantly altered in non-obese hypertensive. Parameters of LV diastolic functions were affected in obese normotensives. 54% of obese normotensives had LV diastolic dysfunction & 58% of non-obese hypertensive had LV diastolic dysfunction. 2% of obese non-hypertensive individuals had LV systolic dysfunction & 6% of non-obese hypertensive had LV diastolic dysfunction. Hypertension significantly affects LV geometry, LV systolic and diastolic function. Obesity affects LV geometry & diastolic functions of LV even in individuals with preserved systolic function.

Comparative Prognostic Value of Echocardiographic Parameters of the Subpulmonary Left Ventricle in Adults With a Systemic Right Ventricle

Comparative Prognostic Value of Echocardiographic Parameters of the Subpulmonary Left Ventricle in Adults With a Systemic Right Ventricle

Technical aspects of fourth ventricle ependymomas in adults: how I do it

BackgroundEpendymomas in the fourth ventricle in adults are rare entity. Surgical treatment of adult ependymomas is the only treatment modality since no other effective alternative is available. Radical resection often means cure but it is hindered by the nature and location of the lesion.MethodsTechnical aspects of the fourth ventricle ependymoma surgery in adults are discussed. Anatomy of the area is provided with the step-by-step surgical algorithm.ConclusionRadical resection of low-grade ependymoma with a detailed understanding of the anatomy in this area is vital considering the high effectiveness of the treatment and its excellent prognosis.

A study of third and fourth ventricular sizes in Bangladeshi adults using computed tomography scan

Background: The assessment of normal measurements of cerebral ventricles in living humans holds significant importance for diagnosing and monitoring various pathologies. Current digital computed tomography (CT) scan machines enable the direct visualization of ventricles in cross-sectional images, allowing real-time measurement of different ventricular dimensions, thereby aiding in comprehending their anatomy. This research aims to create baseline reference values for the sizes of the third and fourth ventricles in normal Bangladeshi adults using CT scans. Methods: This was a retrospective study conducted in the department of radiology and imaging, Shaheed Monsur Ali Medical college hospital, Dhaka, Bangladesh, from January 2023 to December 2023. A total of 408 adult patients with clinical symptoms or history suggestive of neurological ailment were analyzed. CT scans of the brain of all the patients were performed in Supria 128 Fujifilm multi-slice CT scanner and the studies were analyzed retrospectively on Synapse 3D workstation. Measurements were taken with inbuilt linear calipers. The greatest width of the third ventricle (3V) and fourth ventricle (4V) on axial images using a linear approach were measured. Statistical analysis was performed by SPSS version 22.0. Result: The study found that the mean measurements of the 3V were 4.27±1.22 mm in males and 3.73±1.03 mm in females, with an overall mean of 3.92±1.13 mm. For the 4V, the mean measurements were 11.73±1.27 mm in males and 10.67±1.07 mm in females, resulting in an overall mean of 11.03±1.25 mm. The largest dimensions in both ventricles were consistently observed in individuals aged 60 years and above, regardless of gender. Additionally, on average, the measurements of both ventricles were higher in males compared to females. Statistical analysis revealed significant differences in the sizes of both ventricles between male and female subjects. Conclusions: This study concludes normal third and fourth ventricular sizes in Bangladeshi adults using CT scans. These can serve as baseline reference values in our hospital in routine practice.

Kiosk 1Q-FA-09 - Dilated Right Ventricle in Young Adult: Importance of Evaluation with Cardiac Magnetic Resonance Imaging

Kiosk 1Q-FA-09 - Dilated Right Ventricle in Young Adult: Importance of Evaluation with Cardiac Magnetic Resonance Imaging

Truncated radial glia as a common precursor in the late corticogenesis of gyrencephalic mammals.

The diversity of neural stem cells is a hallmark of the cerebral cortex development in gyrencephalic mammals, such as Primates and Carnivora. Among them, ferrets are a good model for mechanistic studies. However, information on their neural progenitor cells (NPC), termed radial glia (RG), is limited. Here, we surveyed the temporal series of single-cell transcriptomes of progenitors regarding ferret corticogenesis and found a conserved diversity and temporal trajectory between human and ferret NPC, despite the large timescale difference. We found truncated RG (tRG) in ferret cortical development, a progenitor subtype previously described in humans. The combination of in silico and in vivo analyses identified that tRG differentiate into both ependymal and astrogenic cells. Via transcriptomic comparison, we predict that this is also the case in humans. Our findings suggest that tRG plays a role in the formation of adult ventricles, thereby providing the architectural bases for brain expansion.

Truncated radial glia as a common precursor in the late corticogenesis of gyrencephalic mammals

The diversity of neural stem cells is a hallmark of the cerebral cortex development in gyrencephalic mammals, such as Primates and Carnivora. Among them, ferrets are a good model for mechanistic studies. However, information on their neural progenitor cells (NPC), termed radial glia (RG), is limited. Here, we surveyed the temporal series of single-cell transcriptomes of progenitors regarding ferret corticogenesis and found a conserved diversity and temporal trajectory between human and ferret NPC, despite the large timescale difference. We found truncated RG (tRG) in ferret cortical development, a progenitor subtype previously described in humans. The combination of in silico and in vivo analyses identified that tRG differentiate into both ependymal and astrogenic cells. Via transcriptomic comparison, we predict that this is also the case in humans. Our findings suggest that tRG plays a role in the formation of adult ventricles, thereby providing the architectural bases for brain expansion.

Multiple coronary artery microfistulae are common and progress in adult patients late after Fontan operation

Abstract Background Coronary angiograms of adult Fontan patients sometimes show the abnormal multiple coronary artery microfistulae (mCAFs) that drain directly into the ventricular chamber. They look like coronary artery fistulae or Thebesian vein. Angiographically detectable mCAFs are a rare finding sometimes associated with myocardial ischemia due to coronary steal and volume overload of ventricles in non-CHD adults. However, there are limited data concerning these mCAFs in the setting of CHD patients. Purpose The aim of this study is to demonstrate presence, character, and changes with growth of mCAFs in adult patients late after Fontan operation. Methods This study is single-center retrospective review of adults (16 years old or older) with Fontan circulation patients who had undergone cardiac catheterization for routine Fontan surveillance between 2009-2022. We assessed the presence of angiographically detectable mCAFs from ascending aortography. After identification of the characteristic cases, we examined the ventricular morphology, the portion of drainage, and compared with previous findings of angiograms. SaO2, EF of main ventricle, CVP, EDP of main ventricle, BNP, and use of pulmonary vasodilators were compared between mCAFs(+) group and mCAFs(-) group. We also reviewed clinical manifestation and findings of exercise stress ECG of the patients. Pulmonary atresia with intact ventricular septum was excluded because abnormal coronary arterial communications have been well documented in this condition. Results Among 90 Fontan patients who had undergone catheterization, significant mCAFs were observed in a total of 18 cases (20%). There were 10 right-dominant single ventricle, 4 left-dominant single ventricle, and 4 unbalanced two ventricles. In all cases, including left-dominant single ventricle, all fistulae drained into right ventricle cavity, never into left ventricle. The patients who underwent serial catheterizations demonstrated that the dilation and tortuosity of fistulae progressed over time. The comparison of two groups showed SaO2 was low, BNP and CVP was high significantly in mCAFs(+) group. There were no significant differences in other factors including age at catheterization and the use of pulmonary vasodilators. Among 10 patients who had underwent exercise stress ECG, only 1 patient showed ST segment depression. None had clinical history of chest pain, and arrhythmia, and ischemic event. Conclusions MCAFs are common and progress in adult patients late after Fontan operation. Although the clinical significance and etiology of these findings remains uncertain, particular attention should be given to subclinical Fontan failure caused by hhigh CVP, volume overload, and myocardial ischemia for the future of adult Fontan patients who have prominent mCAFs.

Nrg1 Regulates Cardiomyocyte Migration and Cell Cycle in Ventricular Development.

Cardiac ventricles provide the contractile force of the beating heart throughout life. How the primitive endocardium-layered myocardial projections called trabeculae form and mature into the adult ventricles is of great interest for biology and regenerative medicine. Trabeculation is dependent on the signaling protein Nrg1 (neuregulin-1). However, the mechanism of action of Nrg1 and its role in ventricular wall maturation are poorly understood. We investigated the functions and downstream mechanisms of Nrg1 signaling during ventricular chamber development using confocal imaging, transcriptomics, and biochemical approaches in mice with cardiac-specific inactivation or overexpression of Nrg1. Analysis of cardiac-specific Nrg1 mutant mice showed that the transcriptional program underlying cardiomyocyte-oriented cell division and trabeculae formation depends on endocardial Nrg1 to myocardial ErbB2 (erb-b2 receptor tyrosine kinase 2) signaling and phospho-Erk (phosphorylated extracellular signal-regulated kinase; pErk) activation. Early endothelial loss of Nrg1 and reduced pErk activation diminished cardiomyocyte Pard3 and Crumbs2 (Crumbs Cell Polarity Complex Component 2) protein and altered cytoskeletal gene expression and organization. These alterations are associated with abnormal gene expression related to mitotic spindle organization and a shift in cardiomyocyte division orientation. Nrg1 is crucial for trabecular growth and ventricular wall thickening by regulating an epithelial-to-mesenchymal transition-like process in cardiomyocytes involving migration, adhesion, cytoskeletal actin turnover, and timely progression through the cell cycle G2/M phase. Ectopic cardiac Nrg1 overexpression and high pErk signaling caused S-phase arrest, sustained high epithelial-to-mesenchymal transition-like gene expression, and prolonged trabeculation, blocking compact myocardium maturation. Myocardial trabecular patterning alterations resulting from above- or below-normal Nrg1-dependent pErk activation were concomitant with sarcomere actin cytoskeleton disorganization. The Nrg1 loss- and gain-of-function transcriptomes were enriched for Yap1 (yes-associated protein-1) gene signatures, identifying Yap1 as a potential downstream effector. Furthermore, biochemical and imaging data reveal that Nrg1 influences pErk activation and Yap1 nuclear-cytoplasmic distribution during trabeculation. These data establish the Nrg1-ErbB2/ErbB4-Erk axis as a crucial regulator of cardiomyocyte cell cycle progression and migration during ventricular development.

Rare Case of Hemorrhagic Atypical Choroid Plexus Papilloma of Fourth Ventricle in Adult: A Diagnostic Dilemma

Choroid plexus papillomas are highly vascular tumors, and such tumors causing subarachnoid hemorrhage have been reported in literature. Similarly, few articles have reported atypical fourth ventricular choroid plexus tumors in adults. However, such an atypical tumor presenting with grossly hemorrhagic transformation without any acute symptoms could not be found in the literature.

Right ventricular cardiac resynchronization therapy in patients with right ventricular conduction delay and heart failure

Right ventricular cardiac resynchronization therapy in patients with right ventricular conduction delay and heart failure

Double outlet right ventricle in adults: Anatomic variability, surgical treatment, and late postoperative complications.

Double outlet right ventricle (DORV) is a highly complex congenital heart disease (CHD) entity, gaining increasing interest due to the rapid progress of cardiac surgery. The number of patients operated for this congenital defect has been growing since 1980s and over following decades with active transitioning of this cohort into the adult medicine. However, the diversity of initial anomaly and performed interventions makes challenging the management of these patients. This is particularly important in the regions where specialized adult CHD cardiology still remains underdeveloped. In this review, we observe the basic principles of DORV nomenclature, main types of the operations and possible late complications. The article focuses on adult patients and offers illustrations from clinical practice.

Development and Evaluation of Prognostic Nomogram Model for Adult Ventricle Glioma Patients

To explore the prognostic factors of adult ventricle glioma (AVG) and to construct and evaluate a survival-related prognostic nomogram model, which could provide further reference for the clinical management of AVG patients. The patients covered in the study were selected from the Surveillance Epidemiology and End Results (SEER) database (1973-2016). They all had definite histological diagnosis of AVG. They were assigned randomly to the training cohort and the validation cohort by random number table at a 2/1 ratio. Survival analysis was performed by Kaplan-Meier analysis. Cox regression analysis was employed to determine the independent prognostic factors for overall survival (OS) and cancer-specific survival (CSS). Then, integrating the basic characteristics of patients, the survival-related nomogram predictive model for OS and CSS in the training cohort was constructed, respectively. After that, internal cross validation and external validation of the model were carried out with the training cohort and the validation cohort in succession. The authenticity and reliability of the nomogram model were evaluated by calculating the concordance index (C-index). Calibration plots were constructed to assess the agreement between the predicted values and the observed values in the training cohort and the validation cohort. A total of 369 AVG patients, including 218 males and 151 females, were included. The median age of the patients was 53. According to the WHO classification of gliomas, 66 (17.9%) patients had grade Ⅱ gliomas, 73 (19.8%) had grade Ⅲ gliomas, and 230 (62.3%) had grade Ⅳ gliomas. Regarding the extent of resection (EOR), 59 (16.0%) had gross total resection (GTR) and 145 (39.3%) had subtotal resection (STR) or partial resection (PR). Of all the patients, 167 (45.3%) received postoperative radiotherapy and 143 (38.8%) received postoperative chemotherapy. Patients were randomized into the training cohort ( n=246) and the validation cohort ( n=123), and there was no significant difference ( P>0.05) in the basic clinical characteristics between the training cohort and the validation cohort. In the training cohort, Cox regression analysis revealed that the independent prognostic factors for OS and CSS included age≥65, grades Ⅲ and Ⅳ according to the WHO classification of gliomas, and not receiving radiotherapy. Furthermore, 5 variables, including age, gender, WHO grades, surgery, and radiotherapy, were used to construct the nomogram model for predicting 6-month, 1-year, and 2-year OS and CSS. The results of internal cross validation in the training cohort showed that the C-indexes of OS and CSS were 0.758 and 0.765, respectively. The external validation results of the validation cohort showed that the C-indexes of OS and CSS were 0.733 and 0.719, respectively. Calibration plots for 6-month, 1-year, and 2-year OS in the training cohort showed relatively good agreement, while in the validation cohort the agreement was relatively low. The 6-month, 1-year, and 2-year CSS calibration plots had results similar to the calibration plots of OS. This nomogram predictive model of OS and CSS showed moderately reliable predictive performance, providing helpful reference information for clinicians to make quick and simple assessment of the survival probability of AVG patients.

Regulation of APD and force by Na+/Ca2+ exchanger in hiPSC-cardiomyocytes

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): BMBF Introduction Human induced pluripotent stem cell-derived cardiomyocytes (HiPSC-CM) are an emerging, powerful tool to study human cardiac physiology, pharmacology and toxicology, to model cardiovascular diseases or even to use for cardiac repair. Understanding the similarities and differences between hiPSC-CM and adult human cardiomyocytes is critical for their use. Here we focus on sodium calcium exchanger (NCX) who plays a crucial role in the Ca2+-homeostasis in the mammalian heart. Importantly, alterations in NCX expression in human heart are associated with various cardiac pathologies such as heart failure or arrhythmias. In order to investigate whether hiPSC-CM could serve as model for adult human heart NCX we measured the properties of NCX in hiPSC-CM and human ventricular tissue. Rat ventricular tissue was used for comparison. Methods HiPSC-CM were differentiated from a healthy iPSC line and dissociated from engineered heart tissue (EHT). Adult human and rat cardiomyocytes were digested from ventricular samples. We measured NCX current by the whole-cell patch clamp technique at 37 °C. Standard sharp microelectrodes were used to record action potentials (AP). Contractile force in human and rat ventricular samples was measured isometrically. A video-optical contractility test system was used to measure force in EHT. SEA0400 (10 µM) was used to block NCX. Results NCX currents could be measured in every hiPSC-CM. The NCX current densities in hiPSC-CM were larger than in human ventricular cardiomyocytes (3.2±0.2 pA/pF n=28 vs. 1.3±0.2 pA/pF n=15, p&amp;lt;0.05), but lower than reported for rat left ventricular cardiomyocytes using the same protocol. SEA0400 shortened APD90 markedly in EHT (264.1±24.9 ms to 191±31.6 ms, n=4) and to a lesser extent in rat ventricular tissue (54.4±3.9 ms to 48.9±4.2 ms, n=7). Shortening in human left ventricular preparations was tiny (320±22.1 ms to 305.5±20.3 ms, n=6) and not different from time-matched controls (TMC). Resting membrane potential, action potential amplitude and upstroke velocity were not affected neither in EHT nor in left ventricular preparations (rat and human). Force was significantly increased by NCX block in rat ventricle (by 31±5.4%, n=18) and EHT (by 20.8±3.9%, n=4), but in human left ventricular preparations there was only a tendency to attenuate spontaneous run-down (-3.7±4.3% n=8 with SEA vs. -6.2±3.7% n=12 in TMC). Conclusion HiPSC-CM possess NCX in the physiological range. HiPSC-CM show NCX-effects on APD and force as predicted from rat ventricle and in full accordance with cardiac physiology. Lack of NCX effect in human adult ventricles that had been already reported previously needs further investigations.

An echocardiographic study of the effect of obesity on systolic and diastolic functions of the left ventricle in hypertensive adults

Objectives: The objectives of the study were to examine the effect of obesity on echocardiographic parameters of systolic and diastolic functions of the left ventricle (LV) in asymptomatic hypertensive adults. Materials and Methods: A cross-sectional study was conducted with 100 individuals (65 males and 35 females). Their blood pressure and body mass index were recorded following which they were divided into obese hypertensives and non-obese hypertensives. Echocardiographic examination was done, and parameters indicating LV geometry and function were recorded. Data were statistically analysed for differences. An unpaired t-test was used considering P &lt; 0.05 as a significant value. Results: Echocardiographic parameters of LV diastolic function were significantly altered in obese hypertensives compared to non-obese hypertensives (P &lt; 0.05). About 58% of non-obese hypertensives and 78% of obese-hypertensives had LV diastolic dysfunction. About 6% of non-obese hypertensives and 8% of obese-hypertensives had LV systolic dysfunction. Conclusion: Obesity in hypertensive individuals adds risk for diastolic dysfunction. The number of subjects falling into categories of mild-to-moderate diastolic dysfunction was considerably higher in the obese hypertensives compared to the non-obese hypertensives.

Isolation of the side population from neurogenic niches enriches for endothelial cells.

In stem cell research, DNA-binding dyes offer the ability to purify live stem cells using flow cytometry as they form a low-fluorescence side population due to the activity of ABC transporters. Adult neural stem cells exist within the lateral ventricle and dentate gyrus of the adult brain yet the ability of DNA-binding dyes to identify these adult stem cells as side populations remains untested. The following experiments utilize the efflux of a DNA-binding dye, Vyrbant DyeCycle Violet (DCV), to isolate bona fide side populations in the mouse dentate gyrus and subventricular zone (SVZ), and test their sensitivity to ABC transporter inhibitors. A distinct side population was found in both the adult lateral ventricle and dentate gyrus using DCV fluorescence and forward scatter instead of the conventional dual fluorescence approach. These side populations responded strongly to inhibition with the ABC transporter antagonists, verapamil and fumitremorgin C. The majority of the cells residing in the side populations of dentate gyrus and SVZ were characterized by their expression of CD31. Additionally, at least 90% of all CD31+ cells found in the dentate gyrus and SVZ were negative for the hematopoietic marker CD45, leading to the hypothesis that the CD31+ cells in the side population were endothelial cells. These findings, therefore, suggest that the side population analysis provides an efficient method to purify CD31-expressing endothelial cells, but not adult neural stem cells.

Role of endoscopic endonasal approach for craniopharyngiomas extending into the third ventricle in adults

•EAA is an innovative, promising, safe and effective approach for 3VCPs.•Key of success is surgeon learning curve in endoscopy and patients selection.•With correct indications, EEA gives GTR and morbidity rate similar to other routes.•Clinical, tumoral and anatomical features should be considered for EEA selection.

Selección de lo mejor del año 2021 en cardiopatías congénitas

This article shows the publications that we consider the most relevant on congenital heart disease in the last year. The COVID-19 pandemic has continued to mark scientific activity in this period. There has been concerns about the risk of complications from COVID-19 among adults with congenital heart disease (CHD). Likewise, the involvement of children with CHD has been studied. This year, the European guidelines for the treatment of CHD have been published, the second edition after 10years, that will be very useful in the treatment of these complex patients. Among the original publications, we highlight the contributions related to risk stratification in the primary prevention of ventricular arrhythmias, Fontan and liver disease, and the progress in percutaneous pulmonary valve implant techniques, the application of new drugs for advanced heart failure in complex CHD and in systemic right ventricle and long-term complications of young adults with transposition of the great arteries undergoing arterial switch surgery.

Abstract 9821: Fully Automated Measurements of Right Ventricular Strain in Children: Validation Using Conventional Manual Technique

Introduction: Fully automated strain measurements have been developed for the left ventricle. However, they have not been studied in the right ventricle (RV) of adults or children. Hypothesis: Automated strain measurements of RV will be comparable with manual strain measurements. Methods: We prospectively enrolled 94 patients, who underwent clinically indicated echocardiograms (mean age: 13.0±4.4 years). Strain measurements included RV free wall longitudinal strain (RVFWLS) and RV “global” longitudinal strain (RVGLS), both measured from the RV-focused apical 4-chamber view. Strain parameters were measured using three methods: 1) Fully automated (AutoStrain, Phillips Medical Systems), 2) Semiautomated (manual correction after automated measurements), 3) Manual measurements (2D-CPA, Tomtec). We also recorded the time required for measurements in all patients. Automated measurements relied on an anatomical intelligence program that was trained by adult datasets. Results: Fully automated measurements were feasible in all cases. However, 40% of patients required manual correction after automated measurements, mostly at the apex and RV lateral annulus at endsystole. The results are depicted in Table 1. Fully automated RVFWS showed moderate to good correlation with manual measurements (r=0.71, p&lt;0.001). Semiautomated measurements showed a stronger correlation (r=0.78, p&lt;0.001) and less bias than fully automated measurements ( Figure 1 ). The time needed for fully and semi-automated analyses were 9±2.6 and 68±25 seconds, respectively (p&lt;0.001). Conclusions: Automated strain may provide rapid and clinically feasible means to assess RV function in children. Presently, a significant number of patients need manual correction, especially at endsystole. We speculate that accuracy of AutoStrain may improve in the future with inclusion of pediatric training datasets, as the anatomical intelligence program currently relies on adult datasets.

Extracellular vesicles derived from physiologically loaded living myocardial slices improve the contractility of healthy living myocardial slices

Abstract Introduction Mechanical load is a determinant of the healthy-to-failing myocardium transition. Extracellular vesicles (EVs) found in the range of 30–200 nm contain bioactive cargoes such as DNA, miRNA and proteins, and thus are considered important mediators of the paracrine crosstalk between cells in health and disease. Living myocardial slices (LMS) are 300μm layers of myocardial tissue that allow modelling of the intercellular communication in the heart. Purpose To assess whether secretion of EVs derived from physiological or pathological mechanically-loaded LMS regulate changes in myocardial contractility. Methods LMS were prepared from adult male Sprague-Dawley rats' left ventricle using a vibratome. LMS were stretched uniaxially using customised stretchers at a sarcomere length of 2.2μm and 2.4μm to recapitulate a physiological (P) and an overload (O) condition, respectively. LMS were cultured for 48-hours under electromechanical stimulation in M-199 media with Earls' salts, catecholamines, dexamethasone and triiodothyronine. After culture, media was harvested and processed for exosomes isolation by size exclusion chromatography. Particle size and concentration was assessed by nanoparticle tracking analysis. To validate the different phenotypes in LMS, force-stretch relationship was assessed after 48-hours culture. EVs isolated from P and O LMS were then used to treat physiologically loaded LMS (1x107 particles/LMS) and the force-stretch relationship was assessed after 48-hours culture. Results No significant difference in contractility was found between P and O LMS at any stretch increment (5.99±1.10 vs 2.82±0.92 mN/mm2 max force), whilst a significant increase in the passive tension of myocardial tissue was observed at 25% (15.90±2.77 vs 4.67±0.37 mN/mm2; p&amp;lt;0.05,) and 30% stretch (21.92±3.60 vs 5.73±0.6 mN/mm2; p&amp;lt;0.001) in the P LMS compared to O LMS (n=11 P, n=4 O). EVs quantification showed no significant difference between P and O conditions (1.16329E+11±4587386608 vs 1.08915E+11±7641744894 particles/ml); (n=7 P; n=3 O). However, P EVs-treated LMS showed a significant increase in contractility after 48-hours, compared to PBS-treated LMS at 25% (8.49±0.62 vs 5.34±0.9 mN/mm2) and 30% stretch (9.55±0.42 vs 5.99±1.10 mN/mm2; p&amp;lt;0.05); (n=11 PBS, n=4 P EVs,) and O EVs-treated LMS from 15–30% stretch (9.55±0.42 vs 3.23±0.55 mN/mm2 max force; p&amp;lt;0.0001); (n=4 P EVs, n=5 O EVs). Conversely, no significant differences in contractility were found between PBS-treated LMS and O EVs-treated LMS (5.99±1.10 vs 3.23±0.55 mN/mm2 maximum force); (n=5 O EVs, n=11 PBS). Conclusions EVs derived from physiologically loaded LMS improve the contractility of healthy LMS after 48-hours culture compared to PBS-treated LMS. Understanding how mechanical load correlates with specific loading of cargoes in EVs may reveal interesting therapeutic targets for the treatment of heart failure. Funding Acknowledgement Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): British Heart Foundation Physiological and overloaded phenotypesContractility of EVs treated LMS