Tracking Imaging Research Articles

Gelatin-coated glutathione depletion and oxygen generators in potentiated chemotherapy for pancreatic cancer

Chemotherapy is generally acknowledged as an effective method for pancreatic cancer (PC). However, its treatment efficacy is often compromised due to inefficient drug delivery and drug resistance propensity of tumor tissues. The purpose of this study is to design and develop a novel drug delivery system (Manganese-doped mesoporous silica nanoparticles, Mn-MSN) in which paclitaxel (PTX), a conventional chemotherapeutic agent used to effectively treat pancreatic cancer clinically. Through cross-linking with glutaraldehyde, gelatin (Ge) was encapsulated on the carrier surface, endowing the nanoparticles (Ge-Mn-MSN@PTX) with excellent biocompatibility, low hemolytic activity, and enzyme-responsive degradation. Mn was added for the following purposes: (1) catalyzing hydrogen peroxide (H2O2) to generate oxygen (O2), thereby alleviating tumor hypoxia and drug resistance; (2) depleting glutathione (GSH), inducing intracellular lipid peroxidation and ferroptosis; (3) enabling real-time monitoring of the therapeutic efficacy of the nanoparticles via magnetic resonance imaging (MRI). The experimental results demonstrated that Ge-Mn-MSN@PTX has satisfactory biosafety, antitumor activity, controlled drug release as well as imaging tracking capabilities. In the SW1990 nude mice model, the Ge-Mn-MSN@PTX effectively inhibited tumor growth by suppressing the expression of the resistance protein P-glycoprotein (P-gp) and inducing ferroptosis. In conclusion, the designed gelatin-coated Mn-MSN shows potential for application in future pancreatic cancer therapy.

Retraction Note: Human motion image detection and tracking method based on gaussian mixture model combined with light sensor

Retraction Note: Human motion image detection and tracking method based on gaussian mixture model combined with light sensor

In Vivo Monitoring and Magnetically‐Enhanced Delivery of CAR T‐Cells to Solid Tumor

AbstractChimeric antigen receptor (CAR) T‐cell therapy demonstrates efficacy for the treatment of hematologic cancers, but remains challenging in solid tumors because of the hostile tumor microenvironment and heterogeneity that restrict the infiltration and activity of CAR T‐cells. The lack of clinical imaging methods to monitor CAR T‐cell therapy in patients limits the potential to enhance the therapeutic approach and predict patient response. Here, a straightforward, non‐invasive method for Magnetic Resonance Imaging (MRI) tracking and magnetic targeting of CAR T‐cells to enhance T‐cell trafficking to solid tumors, in a setting that can be deployed in clinics, is reported. Iron oxide nanoparticles are loaded into T‐cells, allowing MRI detection and magnetic cell guidance, while preserving T‐cell viability, functions, and CAR specificity to target epidermal growth factor receptor (EGFR)‐expressing tumors. Longitudinal MRI monitoring of T‐cells over 14 days reveals differences in tumor infiltration rates and antitumor efficacy between EGFR‐targeted CAR T‐cells and non‐transduced T‐cell. Moreover, an external magnet placed over the tumor enhances the infiltration of CAR T‐cells and increases their antitumor effect. MRI monitoring and magnetic guidance represent a dual‐pronged clinically feasible therapeutic strategy to control and promote CAR T‐cells delivery into solid tumors, thereby improving the precision, efficacy, and safety of the treatment.

Cardiovascular Adaptation in Fetal Growth Restriction: A Longitudinal Study From Fetuses at Term to the First Year of Life.

To investigate longitudinal trends in fetal and offspring cardiovascular adaptation in fetal growth restriction (FGR). Prospective longitudinal study. Fetal Medicine Unit. Thirty-five FGR pregnancies and 37 healthy controls assessed as term fetuses (mean age 37 ± 1 weeks) and again in infancy (mean age 8 ± 2 months). Conventional echocardiographic techniques, tissue Doppler imaging and speckle tracking echocardiography. Left ventricular (LV) and right ventricular (RV) geometry and function. Echocardiographic parameters were normalised by ventricular size adjusting for differences in body weight between groups. Compared to healthy controls, late FGR fetuses showed significant alterations in cardiac geometry with more globular LV chamber (LV sphericity index, 0.56 vs. 0.52), increase in biventricular global longitudinal systolic contractility (MAPSE, 0.29 vs. 0.25 mm; TAPSE, 0.42 vs. 0.37 mm) and elevated cardiac output (combined CO: 592 vs. 497 mL/min/kg, p < 0.01 for all). Indices of LV diastolic function in FGR fetuses were significantly impaired with myocardial diastolic velocities (LV A', 0.30 vs. 0.26 cm/s; IVS E', 0.19 vs. 0.16 cm/s) and LV torsion (1.2 vs. 3.5 deg./cm, p < 0.01 for all). At postnatal assessment, FGR offspring revealed persistently increased SAPSE (0.27 vs. 0.24 mm), LV longitudinal strain (-19.0 vs. -16.0%), reduced LV torsion (1.6 vs. 2.1 deg./cm) and elevated CO (791 vs. 574 mL/min/kg, p < 0.01 for all). Perinatal cardiac remodelling and myocardial dysfunction in late FGR fetuses is most likely due to chronic placental hypoxaemia. Persistent changes in cardiac geometry and function in FGR offspring may reflect fetal cardiovascular maladaptation that could predispose to long-term cardiovascular complications in later life.

Studying Drosophila Larval Behavior in Agarose Channels.

Larvae of the fruit fly Drosophila melanogaster are a popular and tractable model system for studying the development and function of sensorimotor circuits, thanks to the relative numerical simplicity of their nervous system and the wealth of available genetic tools to manipulate the anatomy, activity, and function of specific cell types. Researchers studying the role of a particular gene or cell type in sensorimotor circuit activity or function may wish to observe the effects of an experimental manipulation during behavior in the intact animal. Observing these effects, which may include changes in the intracellular calcium concentration or movement of small numbers of neurons, muscles, etc., typically requires high-spatial-resolution imaging, which poses several difficulties in the freely crawling larva. Freely crawling larvae can move quickly and with changeable heading, making manual or automatic tracking challenging; additionally, they may make three-dimensional movements, such as rearing, that can degrade imaging focus. These challenges are potentially solvable using advanced imaging and algorithmic tracking setups, but cost, space, or development time may be prohibitive. This protocol describes a simple and cost-effective method for placing larvae inside agarose channels, thereby restricting larval crawling to a single dimension and enabling higher-magnification time-series imaging of fluorescently labeled structures during many cycles of locomotion. By using larvae that express fluorescent calcium indicators in cells of interest, researchers can apply this method to study the effects of experimental manipulations on neural or muscular activity during behavior in the intact animal.

The Polycomb system sustains promoters in a deep OFF state by limiting pre-initiation complex formation to counteract transcription

The Polycomb system has fundamental roles in regulating gene expression during mammalian development. However, how it controls transcription to enable gene repression has remained enigmatic. Here, using rapid degron-based depletion coupled with live-cell transcription imaging and single-particle tracking, we show how the Polycomb system controls transcription in single cells. We discover that the Polycomb system is not a constitutive block to transcription but instead sustains a long-lived deep promoter OFF state, which limits the frequency with which the promoter can enter into a transcribing state. We demonstrate that Polycomb sustains this deep promoter OFF state by counteracting the binding of factors that enable early transcription pre-initiation complex formation and show that this is necessary for gene repression. Together, these important discoveries provide a rationale for how the Polycomb system controls transcription and suggests a universal mechanism that could enable the Polycomb system to constrain transcription across diverse cellular contexts.

Identification of an embryonic differentiation stage marked by Sox1 and FoxA2 co-expression using combined cell tracking and high dimensional protein imaging

Pluripotent mouse embryonic stem cells (ESCs) can differentiate to all germ layers and serve as an in vitro model of embryonic development. To better understand the differentiation paths traversed by ESCs committing to different lineages, we track individual differentiating ESCs by timelapse imaging followed by multiplexed high-dimensional Imaging Mass Cytometry (IMC) protein quantification. This links continuous live single-cell molecular NANOG and cellular dynamics quantification over 5-6 generations to protein expression of 37 different molecular regulators in the same single cells at the observation endpoints. Using this unique data set including kinship history and live lineage marker detection, we show that NANOG downregulation occurs generations prior to, but is not sufficient for neuroectoderm marker Sox1 upregulation. We identify a developmental cell type co-expressing both the canonical Sox1 neuroectoderm and FoxA2 endoderm markers in vitro and confirm the presence of such a population in the post-implantation embryo. RNASeq reveals cells co-expressing SOX1 and FOXA2 to have a unique cell state characterized by expression of both endoderm as well as neuroectoderm genes suggesting lineage potential towards both germ layers.

Efficient and Stable NIR-II Phosphorescence of Metallophilic Molecular Oligomers for In Vivo Single-Cell Tracking and Time-Resolved Imaging.

Molecular phosphorescence in the second near-infrared window (NIR-II, 1000-1700 nm) holds promise for deep-tissue optical imaging with high contrast by overcoming background fluorescence interference. However, achieving bright and stable NIR-II molecular phosphorescence suitable for biological applications remains a formidable challenge. Herein, we report a new series of symmetric isocyanorhodium(I) complexes that could form oligomers and exhibit bright, long-lived (7-8 μs) phosphorescence in aqueous solution via metallophilic interaction. Ligand substituents with enhanced dispersion attraction and electron-donating properties were explored to extend excitation/emission wavelengths and enhanced stability. Further binding the oligomers with fetal bovine serum (FBS) resulted in NIR-II molecular phosphorescence with high quantum yields (up to 3.93 %) and long-term stability in biological environments, enabling in vivo tracking of single-macrophage dynamics and high-contrast time-resolved imaging. These results pave the way for the development of highly-efficient NIR-II molecular phosphorescence for biomedical applications.

A Comprehensive Study on Implementation of Deep Learning on Autonomous Vehicle for Steering Angle Prediction and Stability

The development of autonomous vehicles has recently enhanced the transportation industry and opened up a variety of opportunities and problems that can be solved with the aid of current methods and technology. In this study, three separate algorithms were used to predict the steering angle with a track image: Artificial Neural Network (ANN), Convolution Neural Network (CNN), and a combination of CNN and Long-Short Term Memory (CNN-LSTM). The PID controller was employed for benchmarking, which takes Cross-Track Error (CTE) provided by the simulation to steer the vehicle. To achieve improved performance, the standard NVIDIA CNN self-driving model was slightly altered by feeding it with sequential frames. The comparison analysis was conducted using the OpenAI Gym Donkey Simulator.

Mapping the Landscape of VFX and AI: A PRISMA-guided Systematic Review

Objective: This systematic literature review aims to comprehensively synthesize existing evidence on Visual Effects (VFX) and Artificial Intelligence (AI) using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The primary objective is to map the landscape of VFX and AI, examining the historical development of VFX techniques and practices in the context of AI advancements. Methods: Following PRISMA guidelines, a thorough search of five electronic databases—IEEE Xplore, Scopus, Taylor &amp; Francis Online, ACM Digital Library, and ScienceDirect—was conducted to identify articles published up to April 18, 2024. Inclusion criteria encompassed English-language journal articles. Independent reviewers screened articles for eligibility, resolving discrepancies through consensus. Data extraction and synthesis were performed systematically. Results: A total of 41 studies met the inclusion criteria and were included in the review. These studies covered a wide range of topics related to VFX and AI, with various study designs. The findings are presented in a narrative synthesis. Discussion: The review indicates that AI development in VFX is comprehensive, covering topics such as image processing, inpainting, video processing, 3D modelling, rendering, deepfake technology, style transfer, tracking, animation, simulation, rigging, texture compression, and depth map enhancement. These advancements highlight the transformative role of AI in enhancing creative expression, production efficiency, and the quality of visual effects. Conclusion: This systematic literature review provides a comprehensive overview of the current state of knowledge on AI and VFX. The integration of AI into VFX is profoundly transforming the industry, enhancing creative expression, production efficiency, and the quality of visual effects. Continued advancements in AI technologies promise to further revolutionize VFX practices, offering new possibilities and efficiencies for future productions.

Quantitative evaluation of radiation-induced heart disease in patients with lung cancer: a three-dimensional speckle tracking imaging study.

Adverse cardiovascular events due to radiation-induced heart disease (RIHD) have become the leading cause of death in cancer survivors, and early screening for RIHD has become an important clinical issue. Our objective was to determine the utility of three-dimensional speckle tracking echocardiography (3D-STE) for detecting RIHD. According to inclusion and exclusion criteria, patients with lung cancer who received radiotherapy in our hospital for the first time were recruited as subjects. All subjects underwent the conventional echocardiography and 3D-STE examination at six time points (1 day before radiotherapy, 2.5-3 and 5-6 weeks after beginning radiotherapy, and 3-, 6- and 12-month after ending radiotherapy). Routine electrocardiogram, serum cardiac troponin I (cTnI) and clinical data were detected simultaneously. A total of 105 patients with lung cancer were included in the study. Conventional echocardiography found a small amount of pericardial effusion occurred in 8 subjects at 5-6 weeks after beginning radiotherapy. 3D-STE showed that, compared with before radiotherapy, the absolute values of global longitudinal strain (GLS) and global strain (GS) were significantly decreased at 5-6 weeks after beginning radiotherapy (PGLS<0.001, PGS=0.002), and the absolute values of GLS, global radial strain, global circumferential strain, GS were gradually decreased further at 3-, 6- and 12-month after ending radiotherapy (P<0.001). Electrocardiograph showed that 32 subjects had electrocardiograph abnormalities during radiotherapy and 3 had electrocardiograph abnormalities at 3-month after ending radiotherapy, and most returned to normal within 6 months after ending radiotherapy. Patients with lung cancer undergoing radiation therapy have shown a decrease in the function of the left ventricle of the heart while receiving treatment. Combining the assessment of cTnI with GLS can enhance the early detection of radiation-induced heart damage.

Photothermal therapy and cell imaging tracking of porous silicon nanoparticle by magnesiothermic reduction and surface modification

The synthesis of silicon nanoparticles (PSi NPs) from silica nanoparticles (SiO₂) via magnesium (Mg) reduction is a promising technique due to its simplicity and cost-effectiveness. In this study, silica is utilized as the primary precursor and is subjected to a reduction process using magnesium powder as the reducing agent. By covalently attaching Fluorescein Isothiocyanate (FITC) to the surface of PSi NPs, we aim to enhance their fluorescence intensity and stability while also improving their surface reactivity and biocompatibility. The modified PSi NPs system was characterized using various microscopic techniques, Raman spectra, porosity and morphology analysis, Zeta potential, and analysis of organic functional groups to confirm successful conjugation and to evaluate changes in surface morphology, fluorescence properties, and colloidal stability. By leveraging the inherent photothermal conversion efficiency of PSi NPs, we explore their capacity to generate localized heat upon near-infrared (NIR) light irradiation, effectively inducing cancer cell apoptosis. Concurrently, the natural fluorescence of PSi NPs is harnessed to enable high-resolution imaging, facilitating real-time tracking and monitoring of therapeutic processes. The PSi NPs were subjected to a series of in vitro experiments to assess their photothermal efficiency, cytotoxicity, and imaging capabilities. Results demonstrate that PSi NPs exhibit excellent photothermal effects, leading to significant cell death in targeted cancer cells upon NIR exposure, while their fluorescence properties provide clear and detailed imaging. These findings highlight the potential of PSi NPs as multifunctional agents in cancer therapy, combining effective photothermal treatment with non-invasive imaging, thereby enhancing the precision and efficacy of therapeutic interventions.

A Smith Predictor Modified with a Pseudo Feedforward Control for the Charge-Coupled Device-Based Optoelectronic Tracking System.

In the high-precision optoelectronic tracking system (OTS) based on a charge-coupled device (CCD), the boresight error extracted from the tracking image contains an undeniable delay, which directly limits the control bandwidth of visual tracking. High bandwidth means high response speed and tracking accuracy. Generally, a model-based delay compensation control method called the Smith predictor is utilized to separate time delay from the closed loop to promote the control bandwidth. However, due to the existence of errors between the established model and the real object, the improvement in the bandwidth is still limited to ensure system stability, resulting in insufficient tracking performance. In this paper, to solve the problem, a Smith predictor modified with pseudo feedforward control for the OTS is proposed. The experimental results demonstrate that the proposed method achieves significant improvements in tracking performance, reducing the maximum residual error at 1 Hz from 365 arcseconds (using the classic Smith predictor) to 283 arcseconds, a 22.5% improvement. Across the main frequency band (0.2 Hz to 2 Hz), the residual errors were consistently lower using the proposed method.

Advanced MRI-based evaluation of gray and white matter changes in Parkinson’s disease

BackgroundParkinson’s disease (PD) is the most common movement disorder and the second most common neurodegenerative disease. The aim of our study was to compare gray–white matter changes (GWC) between Parkinson's disease (PD) patients and age-matched healthy control group as well as comparing GWC between different stages of PD (early and complicated). Our study was prospective cross-sectional case–control observational study with analytic component conducted on twenty patients and ten controls without any signs or symptoms of PD or any history of PD in first-degree relatives. All patients and controls were tested for history taking with stress on resting tremors, rigidity, gait abnormalities, postural instability and any symptoms of cognitive impairment, clinical examination including general examination and neurological examination. Also diffusion tensor imaging (DTI) with fiber tracking (tractography) and susceptibility-weighted MR imaging were performed for all cases.ResultsAs regards DTI and evaluation of fractional anisotropy (FA) and mean diffusivity (MD) values between PD cases and healthy controls, the cases group showed significant decrease in FA values at substantia nigra on both sides and left cingulum as well as significant increase in MD values at substantia nigra on both sides and corpus callosum. Also, there are significant decrease in FA values at substantia nigra on both sides and significant increase in MD values at substantia nigra on both sides and right cingulum in late parkinsonism when compared to early parkinsonism. A cutoff FA value of 0.945 at right substantia nigra and cutoff FA value of 0.585 at left substantia nigra showed significant AUC that could differentiate between cases and controls. Also cutoff MD value of 0.791 at right substantia nigra and cutoff MD value of 0.813 at left substantia nigra showed significant AUC that could differentiate between cases and controls.ConclusionsDiffusion tensor imaging showed valuable role in evaluation of gray–white matter changes in Parkinson's disease. Also, it helps to assess degree of gray–white matter changes when comparing late parkinsonism to early parkinsonism through evaluation of FA and MD values at corpus callosum, substania nigra, and cingulum.

Image Tracking and Segmentation Algorithms Based on Laser Sensors and Wireless Network Devices in Sports Target Detection

Image Tracking and Segmentation Algorithms Based on Laser Sensors and Wireless Network Devices in Sports Target Detection

Hybrid learning architecture for high-speed railroad scene parsing and potential safety hazard evaluation of UAV images

Potential safety hazards (PSHs) around tracks need to be accurately and timely detected to ensure high- speed railroad operating safety. Unmanned aerial vehicle (UAV)-based railroad inspection has potential to complement visual inspections by providing better overhead views and mitigating safety concerns. This paper proposes a hybrid learning architecture, named YOLORS (you only look once railroad scene), to parse driveways and tracks in UAV images, and evaluate PSHs along tracks. First, a stripe-pool-based parsing branch is designed and assembled in YOLORS to precisely accomplish the pixel-level parsing tasks. Second, a new data augmentation method called object-guided mosaic is developed and incorporated into the architecture for improving small object detection performance. Finally, extensive experiments indicate YOLORS demonstrates exceptional performance in both pixel-level parsing and object detection tasks, which outperforms the current advanced models. This proposed approach can quickly convert UAV imagery containing complicated railroad scenes into useful information with a high detection rate.

Vpit: real-time embedded single object 3D tracking using voxel pseudo images

In this paper, we propose a novel voxel-based 3D single object tracking (3D SOT) method called Voxel Pseudo Image Tracking (VPIT). VPIT is the first method that uses voxel pseudo images for 3D SOT. The input point cloud is structured by pillar-based voxelization, and the resulting pseudo image is used as an input to a 2D-like Siamese SOT method. The pseudo image is created in the Bird’s-eye View (BEV) coordinates; and therefore, the objects in it have constant size. Thus, only the object rotation can change in the new coordinate system and not the object scale. For this reason, we replace multi-scale search with a multi-rotation search, where differently rotated search regions are compared against a single target representation to predict both position and rotation of the object. Experiments on KITTI [1] Tracking dataset show that VPIT is the fastest 3D SOT method and maintains competitive Success and Precision values. Application of a SOT method in a real-world scenario meets with limitations such as lower computational capabilities of embedded devices and a latency-unforgiving environment, where the method is forced to skip certain data frames if the inference speed is not high enough. We implement a real-time evaluation protocol and show that other methods lose most of their performance on embedded devices; while, VPIT maintains its ability to track the object.

Automatic Surgery in Transcatheter Aortic Valve Replacement Using Augmented Reality.

Augmented Reality (AR) is in high demand in medical applications. The aim of the paper is to provide automatic surgery using AR for the Transcatheter Aortic Valve Replacement (TAVR). TAVR is the alternate medical procedure for open-heart surgery. TAVR replaces the injured valve with the new one using a catheter. In the existing model, remote guidance is given, while the surgery is not automated based on AR. In this article, we deployed a spatially aligned camera that is connected to a motor for the automation of image capture in the surgical environment. The camera tracks the 2D high-resolution image of the patient's heart along with the catheter testbed. These captured images are uploaded using the mobile app to a remote surgeon who is a cardiology expert. This image is utilized for the 3D reconstruction from 2D image tracking. This is viewed in a HoloLens like an emulator in a laptop. The surgeon can remotely inspect the 3D reconstructed images with additional transformation features such as rotation and scaling. These transformation features are enabled through hand gestures. The surgeon's guidance is transmitted to the surgical environment to automate the process in real-time scenarios. The catheter testbed in the surgical field is controlled by the hand gesture guidance of the remote surgeon. The developed prototype model demonstrates the effectiveness of remote surgical guidance through AR.

Motion analysis comparing surface imaging and diaphragm tracking on kV projections for deep inspiration breath hold (DIBH)

BackgroundSurface-guided imaging (SGI) is increasingly utilized to monitor patient motion during deep inspiration breath hold (DIBH) in radiotherapy. Understanding the association between surface and internal motion is crucial for effective monitoring. PurposeTo investigate the relation between motion detected by SGI using surface-guided radiotherapy (SGRT) and internal motion measured through diaphragm tracking on kV projections acquired with DIBH for online CBCT. MethodsBoth SGI and kV were simultaneously acquired for ten patients over a total of 200 breath holds (BH). Diaphragm tracking was performed using second-degree polynomial curve fitting on the derivative images for each kV projection and high-pass filtering at 1/30 Hz to remove rotational effects. The superior-inferior (SI) and anterior-posterior (AP) motions of SGI were then compared to kV tracking using various statistical measures. ResultsThe correlation (individuals’ median: −0.07 to 0.73) was a suboptimal metric for the BH data. The median and 95th percentile absolute differences between SGI-SI and kV were 0.73 mm and 3.46 mm, respectively, during DIBH. For SGI-AP, the corresponding values were 0.55 mm and 2.80 mm. For inter-BH measurements, the contingency table based on a 3 mm threshold indicated surface/diaphragm motion agreement for SGI-SI/kV and SGI-AP/kV was 61 % and 56 %, respectively. ConclusionBoth intra- and inter-BH measurements indicated a limited association between surface and diaphragm motion, with certain constraints noted due to kV tracking and DIBH data. These findings warrant further investigation into the association between surface and internal motion.

Advanced myocardial deformation echocardiography for evaluation of the athlete's heart: Functional and mechanistic analysis

BackgroundAssessment of the athlete's heart is challenging because of a phenotypic overlap between reactive physiological adaptation and pathological remodelling. The potential value of myocardial deformation remains controversial in identifying early cardiomyopathy. AimTo identify the echocardiographic phenotype of athletes using advanced two-dimensional speckle tracking imaging, and to define predictive factors of subtle left ventricular systolic dysfunction. MethodsIn total, 191 healthy male athletes who underwent a preparticipation medical evaluation at Nancy University Hospital between 2013 and 2020 were included. Clinical and echocardiographic data were compared with 161 healthy male subjects from the STANISLAS cohort. Borderline global longitudinal strain value was defined as<17.5%. ResultsAthletes demonstrated lower left ventricular ejection fraction (57.9±5.3% vs. 62.6±6.4%; P<0.01) and lower global longitudinal strain (17.5±2.2% vs. 21.1±2.1%; P<0.01). No significant differences were found between athletes with and without a borderline global longitudinal strain value regarding clinical characteristics, structural echocardiographic features and exercise capacity. A borderline global longitudinal strain value was associated with a lower endocardial global longitudinal strain (18.8±1.2% vs. 22.7±1.9%; P=0.02), a lower epicardial global longitudinal strain (14.0±1.1% vs. 16.6±1.2%; P<0.01) and a higher endocardial/epicardial global longitudinal strain ratio (1.36±0.07 vs. 1.32±0.06; P<0.01). No significant difference was found regarding mechanical dispersion (P=0.46). ConclusionsBorderline global longitudinal strain value in athletes does not appear to be related to structural remodelling, mechanical dispersion or exercise capacity. The athlete's heart is characterized by a specific myocardial deformation pattern with a more pronounced epicardial layer strain impairment.