Correlation across modalities and clinical phenotypes between left Ventricular global longitudinal strain by echocardiography and cardiac magnetic resonance.

The mechanisms underlying the clinical benefit of intravenous iron in patients with heart failure (HF), left ventricular ejection fraction (LVEF) < 50%, and iron deficiency (ID) remain incompletely defined. Clinical evidence suggests that iron repletion may improve ventricular synchrony and augment the response to cardiac resynchronization therapy (CRT). The longitudinal systolic dyssynchrony index (L-SDI), derived from cardiac magnetic resonance feature tracking (CMR-FT), provides a non-invasive measure of mechanical dyssynchrony. This subanalysis of the Myocardial-IRON trial evaluated the short-term effects of ferric carboxymaltose (FCM) on L-SDI and explored its relationship with global left ventricular longitudinal strain (GLS). In this post hoc analysis of the randomized, double-blind, placebo-controlled Myocardial-IRON trial (NCT03398681), 51 of 53 ambulatory patients (96.2%) with stable HF, LVEF < 50%, and ID underwent CMR-FT at baseline, and at 7-day, and 30-days post-FCM. Linear mixed-effects models assessed the effect of FCM versus placebo on L-SDI, including subgroup analyses by baseline QRS duration, and evaluated associations between changes in L-SDI and changes in GLS, T2*, and T1-mapping. Data are presented as mean ± SD or median (IQR), as appropriate. The participants have a mean age of 70.4 ± 9.6 years, with a median CMR-derived LVEF of 38.5% (IQR 33-45); the mean global longitudinal strain is -7.5 ± 3.6%. FCM leads to a greater reduction in L-SDI over time versus placebo (omnibus p = 0.015), with significance at 30 days (Δ=-3.8; 95% CI -6.9 to -0.7; p = 0.011). The benefit is most pronounced in patients with baseline electrical dyssynchrony (interaction p < 0.001). Improvements in L-SDI are strongly associated with GLS gains (p < 0.001) and myocardial iron uptake [T2*changes (p = 0.045) and T1-mapping changes (p = 0.011)]. In HF with LVEF < 50% and ID, FCM improves short-term LV mechanical synchrony, particularly in those with electrical dyssynchrony, and this is linked to enhanced systolic function and greater myocardial iron repletion.

ABSTRACT This article presents a comparative analysis of positron emission particle tracking (PEPT) and magnetic particle tracking (MPT) experiments with coupled discrete element method (DEM) and smooth‐particle hydrodynamics (DEM–SPH) simulations in the context of a horizontal stirred mill. The study examines grinding media dynamics within the mill and validates experimental techniques against computational simulations. Volume fraction and velocity distributions from the PEPT and DEM–SPH simulations show similar trends, with MPT in partial agreement due to lower resolution. Although PEPT is advanced yet costly, MPT and DEM–SPH serve as complementary tools. This study highlights the effectiveness and applicability of various tracking and simulation methodologies in studying stirred media mill dynamics.

BackgroundCardiovascular complications are the primary cause of mortality in patients with Duchenne muscular dystrophy (DMD). However, the dynamic progression underlying myocardial damage in DMD has not yet been fully elucidated. This study aimed to quantitatively assess myocardial dysfunction in patients with DMD across different age groups via cardiac magnetic resonance (CMR) tissue tracking technology.MethodsBetween August 2018 and January 2020, 110 patients with DMD diagnosed at the Pediatric Neurology Outpatient Department of West China Second University Hospital were consecutively and prospectively included in the study. The patients were categorized into three age groups: 3–6, 7–10, and 11–14 years. Based on left ventricular ejection fraction (LVEF), the patients were further divided into a normal LVEF group (LVEF ≥55%) and a decreased LVEF group (LVEF <55%). Furthermore, based on the presence of delayed enhancement, patients were classified into late gadolinium enhancement (LGE)-positive and LGE-negative groups. Additionally, 69 healthy controls were recruited for comparison. Left ventricular functional parameters and CMR tissue tracking-related parameters, such as global and regional myocardial strain of the left ventricle, were assessed. These included radial, circumferential, and longitudinal peak strains at the base, middle, and apex of the left ventricle. Statistical analyses were conducted via the t-test.ResultsA total of 99 patients and 61 healthy controls were included in the study. In comparison to the control group (n=21), patients aged 3–6 years in the DMD group (n=15) did not exhibit any decline. Patients aged 7–10 years in the DMD group (n=63), as compared with the control group (n=18), had lower LVEF (59.58%±7.09% vs. 63.39%±5.27%, P=0.044) and left ventricular global radial (37.34%±9.78% vs. 42.95%±9.22%, P=0.03), circumferential (−20.75%±3.77% vs. −22.09%±2.46%, P=0.03), and longitudinal (−13.91%±2.81% vs. −15.69%±2.52%, P=0.04) strain. Patients aged 11–14 years in the DMD group (n=21), as compared with the control group (n=22), demonstrated an even greater reduction in strain in the left ventricle for all parameters, except for LVEF. For patients in the normal LVEF group (n=77) or LGE-negative group (n=51), despite there being no significant difference in cardiac function compared with the control group, the global and regional myocardial strain of left ventricle was decreased.ConclusionsMyocardial dysfunction predominantly manifests in DMD among children older than 7 years, exhibiting a subtle progression that exacerbates with advancing age. The myocardial injury tends to develop from the basal epicardium toward the apical and endocardial regions.

To assess the association between circulating polyunsaturated fatty acids (PUFAs) and left cardiac myocardial strain in hypertensive patients using cardiac magnetic resonance feature tracking. This retrospective study included 364 patients with preserved left ventricular ejection fraction (179 hypertensive, 185 controls). Left atrial (LA) and left ventricular (LV) strain parameters were derived from CMR images using CVI42 software. Group comparisons were performed using independent t-tests, ANCOVA, Mann-Whitney U tests, or chi-square tests as appropriate. Univariate and multivariable linear regression were used to examine associations between ω-3 PUFA levels and myocardial strain parameters. Logistic regression and ROC curve analysis were conducted to evaluate predictive value. Inter-observer agreement was assessed using intraclass correlation coefficients. After adjustment for age, sex, BMI, blood pressure, triglycerides, and creatinine, no significant differences in ω-3 PUFA levels or their subtypes were observed between groups (all p > 0.05). In hypertensive patients, docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) were independently and negatively associated with multiple LV strain parameters, including mid-wall longitudinal strain, global radial strain, mid-wall radial strain, mid-wall circumferential strain, and apical longitudinal strain, as well as LA functional parameters, including reservoir strain and strain rate (all p < 0.05). Sex differences were noted: only DHA was negatively associated with apical radial strain in males, whereas DHA, DPA, and EPA were negatively associated with multiple LV basal and global strain parameters in females (all p < 0.05). ROC analysis showed DHA and DPA had moderate predictive value for LV dysfunction (AUC 0.613, 0.602), while DHA, EPA, and total ω-3 predicted LA dysfunction (AUC 0.612, 0.609, 0.629). Blood ω-3 PUFA levels in hypertensive patients are independently associated with impaired left cardiac myocardial strain and increased dysfunction risk, an effect observed only in the hypertensive group. Different ω-3 subtypes demonstrate predictive value for left cardiac dysfunction. LV dysfunction is primarily associated with DHA and DPA, while LA dysfunction with EPA and total ω-3. Female patients are more sensitive to this effect. Blind ω-3 supplementation should be avoided, and sex-specific management strategies considered.

Abstract Electron Beam Additive Manufacturing (EBAM) requires a focusing system capable of both precise focusing and dynamic adjustability. This paper presents the design, optimization, and experimental validation of a dual-ring adjustable permanent magnet strong-focusing system based on a Halbach array, intended to replace conventional electromagnetic solenoids in EBAM. To accommodate the distinct requirements of high-energy-density melting and uniform preheating/annealing, a system comprising three permanent magnet quadrupole units was developed. Each unit features two concentric rings of octagonal magnets arranged in a Halbach configuration, enabling dynamic beam spot adjustment through the relative rotation of the outer ring. The mechanical structure, including rotatable yokes and shielding end plates, was optimized to ensure precise motion and suppress fringe field interference. Beam matching simulations determined the optimal magnetic field parameters, and a prototype was fabricated using Samarium-Cobalt magnets. Comprehensive magnetic field measurements and particle tracking simulations confirmed the system's performance: achieving a fine focus spot with a radius of 0.0905 mm for melting and a larger, uniform spot of 0.4418 mm for preheating/annealing. The measured field distributions deviated from simulations by less than 1%, validating the efficacy of the proposed quadrupole field adjustment scheme. This work demonstrates an energyefficient focusing solution for EBAM, eliminating the need for high-power, water-cooled solenoid systems.

BackgroundRecently, there has been a resurgence in the incidence of Mycoplasma pneumoniae pneumonia (MPP) among children, but little is known about Mycoplasma pneumoniae (MP) infection in children’s hearts.MethodsChildren diagnosed with MPP received non-contrast cardiac magnetic resonance (CMR) assessments during hospitalization and at three months following discharge. A control group consisting of healthy children was also included.ResultsChildren with MPP exhibited significantly decreased left ventricular (LV) ejection fraction (EF), LV cardiac output (CO), LV cardiac index (CI), LV end-diastolic volume (EDV)/body surface area (BSA), LV stroke volume (SV)/BSA, and LV global longitudinal strain (GLS) compared to controls (p < 0.05). The global native T1 and T2 values of the baseline group were higher than those of controls (p < 0.05). The follow-up group showed improvements in LV SV/BSA, LVEF, right ventricle (RV) EF, heart rate (HR), LV GLS, LV global radial strain (GRS), and LV global circumferential strain (GCS) compared to three months prior, but maintained lower LV CI, LV EDV/BSA, LV end-systolic volume (ESV)/BSA, and LV SV/BSA compared to the control group (p < 0.05).ConclusionsMycoplasma pneumoniae infection might affect LV function in children. The LVEF and myocardial strain generally show good recovery after three months, although some children may continue to exhibit abnormalities in other cardiac function parameters or imaging signs of cardiac inflammation.

Prospective operational feasibility, safety, and workflow of magnetic resonance-guided tracking technology for interstitial gynecologic brachytherapy.

Abstract Control of the amplitude and rotation of low-frequency kink or tearing perturbations in a tokamak plasma is crucial to disruption avoidance. For many actuator solutions (e.g. direct application of coupled magnetic fields or current drive), accurate knowledge of the instantaneous location of the mode is a requirement. This work demonstrates that equivalent realtime control of mode frequency using applied resonant magnetic fields can be obtained through tracking the rotating mode using either simple tomographic analysis of optical fluctuations, or by using previously proven tracking of edge magnetic fluctuations. In these experiments, the HBT-EP tokamak observes coupled 2/1-3/1 tearing kink modes, the phase of which is determined magnetically by an array of 10 × 4 toroidal by poloidal B θ Mirnov probes, with the angle extracted by realtime projection of the signal onto an ideal 3/1 shape on a GPU in a 15µs control loop. Alternatively, the phase of the 2/1 internal tearing mode is extracted using realtime tomographic inversion of signals from the poloidal EUV (pEUV) diagnostic on the GPU, using fixed-weighting ∇ 2 Tikhonov regularization. In offline computations, this implementation choice performs as well or better than regularization kernels of Gaussian Process Tomography or lower order finite difference operators, as well as iterative optimized weighting routines or directly fitting an m = 2 shape to the incoming pEUV signals, vs the magnetic scheme. Using either magnetic or optical phase tracking, mode rotation changes of ∆f n=1 ≈ [-30%, +20%] are obtained in realtime experiments by applying a resonant magnetic field with fixed temporal phase offset to the rotating mode.

Precision-enhancing magnetic needle tracking system in ultrasound-guided fine needle aspiration of head and neck lesions: a novel image-guided technique.

Cardiac chamber strain is associated with outcomes in various diseases. However, it remains uncertain whether left ventricular global longitudinal strain (LVGLS), left atrial reservoir strain (LASr), or right ventricular free wall longitudinal strain (RVfwLS) has the most robust association with outcomes. The authors aimed to compare head-to-head the associations of LVGLS, LASr, and RVfwLS with major adverse cardiovascular events (MACE) using 2-dimensional speckle tracking echocardiography (2D-STE) and cardiac magnetic resonance feature tracking (CMR-FT). Consecutive patients who underwent clinically indicated echocardiography and cardiac magnetic resonance on the same day were enrolled. Strain was derived from 2D-STE (fully automated and manually edited) and CMR-FT. The primary endpoint was MACE, including cardiac death, heart failure hospitalization, and sustained ventricular tachyarrhythmia. We included 550 patients (age 65 ± 15 years, 361 [66%] male). Over a median follow-up of 2.2 years (Q1-Q3: 0.9-4.2 years), 78 (14.3%) patients experienced MACE. LVGLS, LASr, and RVfwLS were independently associated with MACE in separate models after adjusted for key clinical variables. Head-to-head comparisons of 3 strain parameters revealed that LASr remained significantly associated with MACE using 2D-STE (both fully automated and manually edited, HR: 0.91; 95% CI: 0.86-0.95) and CMR-FT (HR: 0.91; 95% CI: 0.86-0.96) (all P ≤ 0.001). Incremental analysis showed that LASr provided additional value beyond clinical parameters and LVGLS (all P < 0.001), while the subsequent addition of RVfwLS did not. Nomogram analyses indicated that LASr had the most significant impact on MACE compared with LVGLS and RVfwLS, as assessed by both 2D-STE and CMR. Compared with LVGLS and RVfwLS, LASr exhibited the strongest association with MACE, regardless of the imaging modality used. Incorporating LASr as a routine measurement should therefore be considered.

This article presents the first co-designed MRI imaging and magnetic positioning system for real-time dynamic motion compensation, achieving sub-millimeter tracking accuracy while preserving diagnostic image quality. The core innovation lies in a system-level co-design of an MRI imaging system and a magnetic localization system, featuring a customized receiver IC for processing magnetic signals coupled by the frontend RF coils, enabling artifact-free MRI imaging in dynamic scenarios. This integration enables a median positioning accuracy of 0.66 mm across a 40 × 40 × 50 cm3 field-of-view with a total power consumption of 997 μW. The key innovations include: 1) a time-division multiplexing scheme to enable signal detection from different coils while achieving spectral isolation between 1.4 MHz positioning signals and MRI Larmor frequencies through FPGA-synchronized blanking; 2) a dynamic calibration algorithm fusing magnetic tracking data with multi-frame MRI imaging, reducing spatial blur radius by 40% via weighted averaging; 3) an MRI-optimized Levenberg-Marquardt algorithm incorporating dynamic magnetic beacon weighting and spatial constraints, improving localization accuracy by 53% versus conventional algorithm. The system utilizes planar magnetic beacons with a dimension of 3 × 3 cm2, reducing spatial occupancy compared to prior designs. This work bridges critical gaps between high-precision tracking and artifact-free MRI, enabling real-time imaging of non-autonomous motion and respiratory motion compensation, representing a paradigm shift for MRI-guided interventions.

To investigate the diagnostic value of cardiac magnetic resonance imaging feature tracking (CMR-FT) in evaluating patients with non-dilated left ventricular cardiomyopathy (NDLVC) and either reduced or preserved left ventricular ejection fraction (LVEF). This retrospective study enrolled 60 patients with NDLVC, including 30 with reduced LVEF (NDLVC-rLVEF, LVEF < 50%) and 30 with preserved LVEF (NDLVC-pLVEF, LVEF ≥ 50%), along with 30 healthy controls. Using the CVI42 post-processing software, conventional left ventricular functional parameters and 2D/3D global strain parameters were obtained, including global radial strain (GRS), global circumferential strain (GCS), and global longitudinal strain (GLS). Group differences in these parameters were analyzed. The diagnostic efficacy of strain parameters in NDLVC patients with reduced LVEF was evaluated using receiver operating characteristic (ROC) curve analysis. (1) Compared to the NDLVC-pLVEF group, the NDLVC-rLVEF group was older (P < 0.05) and had a higher prevalence of hyperlipidemia and alcohol consumption history. (2) Compared to the control group, the NDLVC-pLVEF group showed a significant increase in LV mass at ED (P < 0.05). Compared to the NDLVC-pLVEF group, the NDLVC-rLVEF group exhibited significantly increased left ventricular end-systolic volume (LVESV) and LV mass at ED (P < 0.05), while left ventricular stroke volume (LVSV), left ventricular cardiac output (LVCO), left ventricular ejection fraction (LVEF), absolute values of GRS (2D/3D), GCS (2D/3D), GLS (2D/3D) were significantly reduced (P < 0.05). (3) ROC curve analysis revealed that the AUC values for GRS (2D), GCS (2D), GLS (2D), GRS (3D), GCS (3D), and GLS (3D) in distinguishing the NDLVC-rLVEF group from NDLVC-pLVEF group were 0.980, 0.974, 0.941, 0.908, 0.981, and 0.843, respectively. CMR-FT technique demonstrates significant diagnostic value in differentiating NDLVC patients with both reduced and preserved LVEF. Both 2D and 3D strain parameters exhibit high diagnostic efficacy.

The 2D projective nature of X-ray radiography presents significant limitations in fluoroscopy-guided interventions, particularly the loss of depth perception and prolonged radiation exposure. Integrating magnetic trackers into these workflows is promising; however, it remains challenging and under-explored in current research and practice. To address this, we employed a radiolucent magnetic field generator (FG) prototype as a foundational step towards seamless magnetic tracking (MT) integration. A two-layer FG mounting frame was designed for compatibility with various C-arm X-ray systems, ensuring smooth installation and optimal tracking accuracy. To overcome technical challenges, including accurate C-arm pose estimation, robust fluoro-CT registration, and 3D navigation, we proposed the incorporation of external aluminum fiducials without disrupting conventional workflows. Experimental evaluation showed no clinically significant impact of the aluminum fiducials and the C-arm on MT accuracy. Our fluoro-CT registration demonstrated high accuracy (mean projection distance $\approx$ 0.7 mm), robustness (wide capture range), and generalizability across local and public datasets. We conducted a phantom insertion experiment using endoleak repair as a representative procedure. Needle insertion error was between 2 mm and 3 mm, with real-time guidance using enhanced 2D and 3D navigation. Overall, our results demonstrated the efficacy and clinical applicability of the MT-assisted approach. To the best of our knowledge, this is the first study to integrate a radiolucent FG into a fluoroscopy-guided workflow.

Abstract The ensemble Kalman filter (EnKF) method, which is used for magnetic target tracking, involves extensive sampling and requires significant computational effort. To address these issues, we propose PC-EnKF, a tracking method based on polynomial chaos expansion. PC-EnKF employs polynomial chaos expansion to approximate the system’s state probability distribution, thus eliminating the need for extensive sampling. First, we use the magnetic dipole model to preliminarily locate the target using the particle swarm optimization (PSO) algorithm and use this as the initial value of the PC-EnKF. Next, we use PC-EnKF to track the moving magnetic dipole target. Simulation experiments demonstrate that the tracking error of PC-EnKF is approximately 18.7% lower than that of EnKF, given an identical number of sampling points and a high signal-to-noise ratio.

• TEOS:APTES ratio dictates silica shell thickness, morphology, and charge. • DOE reveals how core geometry and loading modulate encapsulation outcomes. • Design rules enable tailoring silica-coated IONPs for biomedical applications. Silica-coated iron oxide nanoparticles are widely used in biomedicine, yet the relationships between several reaction parameters like precursor chemistry, core morphology, and particle loading, that govern coating physico-chemical properties, remain poorly defined. Here, we systematically disentangle these factors using a combination of scanning transmission electron microscopy (S(T)EM), surface charge analysis, magnetic saturation characterization ( Ms ), analytical centrifugation (AC), and nanoparticle tracking analysis (NTA). Initial experiments revealed that tetraethyl orthosilicate (TEOS) alone produced fused, irregular shells, whereas co-condensation with (3-Aminopropyl)triethoxysilane (APTES) yielded discrete, rounded shells with tunable thickness, surface charge, and yield. A custom design-of experiments (DOE) study across spherical and cubic cores (5 or 10 mg loadings; TEOS: APTES = 170:15, 140:45, 110:75 µL) established clear structure–property relationships. TEOS-rich conditions generated thin, single-core shells, while intermediate ratios promoted multi-core architectures with moderate thickness. APTES-rich conditions produced thick, amine functionalized shells, and multi-core encapsulation. Particle loading further modulated coating uniformity, with lower mass favoring thicker shells. These results provide guidelines to rationally tune silica-coated IONPs for application-specific needs, especially in biomedicine.

Background: Relative apical sparing of longitudinal strain is widely used as a diagnostic marker of cardiac amyloidosis. However, similar deformation patterns have been reported in other cardiac diseases, raising concerns regarding disease specificity. A comprehensive multimodality synthesis of the relative apical sparing pattern (RASP) across disease entities is lacking. Methods: A systematic review and meta-analysis were conducted according to PRISMA guidelines. PubMed, Scopus, and EMBASE were searched through December 2025 for studies reporting RASP or regional longitudinal strain values allowing standardized RASP calculation. Cardiac amyloidosis and major phenocopies-including aortic stenosis, hypertrophic cardiomyopathy, hypertensive heart disease, Fabry disease, mitral valve prolapse, and other cardiomyopathies-were included. Random-effects models were used to compare cardiac amyloidosis with non-amyloid conditions using standardized mean differences (SMDs), with subgroup analyses according to imaging modality (two-dimensional speckle-tracking echocardiography [2D-STE] versus cardiac magnetic resonance feature tracking [CMR-FT]). Results: Fourteen studies (nine 2D-STE and five CMR-FT) were included in the quantitative synthesis. Overall, cardiac amyloidosis was associated with significantly higher RASP compared with non-amyloid conditions (SMD 0.676, 95% CI 0.493-0.860; p < 0.001), with substantial heterogeneity (I2 = 96.9%). Modality-stratified analyses showed a very large pooled effect for 2D-STE (SMD 2.152, 95% CI 1.354-2.950; I2 = 97.6%) and a moderate, homogeneous effect for CMR-FT (SMD 0.594, 95% CI 0.405-0.782; I2 = 0%). Sensitivity analyses confirmed robustness. No significant publication bias was detected by Egger's test. Conclusions: Relative apical sparing is not specific to cardiac amyloidosis but is most pronounced in this condition. Its diagnostic magnitude varies across modalities and clinical contexts, supporting a multiparametric, modality-specific interpretation.

BackgroundThe application of ultrahigh-field cardiac magnetic resonance imaging (MRI), such as 9.4 T imaging, in mouse models remains challenging, especially under rapid heart rates (500–600 beats per minute), and its feasibility and reproducibility have yet to be thoroughly studied. Therefore, this study aimed to evaluate the feasibility and reproducibility of combining cardiac magnetic resonance feature tracking (CMR-FT)-derived strain parameters and conventional cardiac MRI parameters to image an acute experimental autoimmune myocarditis (EAM) mouse model under a 9.4 T ultrahigh field system and to assess its potential for the early diagnosis of acute EAM.MethodsThis retrospective study (conducted from December 2023 to December 2024) included 45 male BALB/c mice (30 EAM mice and 15 controls). EAM mice were injected with Complete Freund’s Adjuvant (CFA; Sigma-Aldrich) to induce myocarditis. The control mice were treated with equal amounts of normal saline at the same time and position as those in experimental mice. CMR was performed with a 9.4 T scanner (Biospec 94/30; Bruker BioSpin) at 7 days, which included precontrast T1, postcontrast T1 and T2, and extracellular volume fraction (ECV) mapping. Left ventricular (LV) strain was evaluated via feature tracking. The diagnostic performance of CMR was evaluated through receiver operating characteristic (ROC) analysis.ResultsA total of 45 mice (30 EAM mice and 15 controls) were included. All parameters were feasible in the mice that underwent CMR, and there was excellent reliability, as indicated by intraclass correlation coefficients greater than 0.9 for both intra- and interobserver agreement across all parameters. Intra- and interobserver agreement was analyzed by intraclass correlation coefficients (ICC). EAM mice demonstrated significantly impaired strain parameters compared to healthy controls [global radial strain (GRS): 34.07%±2.49% vs. 38.20%±2.76%, P<0.001; global circumferential strain: –19.44%±1.40% vs. –21.4%±2.37%, P=0.001; global longitudinal strain: –17.03%±1.64% vs. –19.04%±2.03%; P=0.001]. In ROC analyses, combining GRS with T2 generated the best parameter for identifying acute myocarditis (area under the curve, 0.882; sensitivity, 88.7%; specificity, 82.0%) and provided incremental diagnostic value.ConclusionsThe feasibility of LV strain parameters combined with CMR conventional sequences in identifying EAM in mice at 9.4 T CMR has good reproducibility. For mice with preserved LV ejection fraction, the combination of T2 and GRS can significantly increase the ability to predict EAM within 7 days and provides incremental value as compared to conventional CMR parameters.

The brain has evolved multiple times across evolution; the human prefrontal cortex (PFC) represents its latest developmental addition. Evolution has led to similarities in brain design across species and comparable solutions can be found in different species. The common marmoset shares ancestry with the human primate and serves as a useful model for human PFC build. Previous research approaches on major depressive disorder (MDD) and obsessive-compulsive disorder (OCD) have led to the definition of psychopathological sub-networks including their cortico-subcortical connections. Diffusion tensor magnetic resonance imaging fiber tracking (DTI-FT) is used in humans as a non-invasive substitute for invasive viral tract tracing (AAVaTT) technologies applied in non-human primates. We here compare DTI-FT (N = 1000) and AAVaTT (n = 52) in humans and marmosets, respectively, to reveal interspecies anatomical and functional distinctions of PFC connectivity models and putative effects on dysfunctional networks relevant for MDD and OCD.

ObjectiveTo evaluate the utility of cardiac magnetic resonance feature tracking (CMR-FT) and T1 mapping in quantifying myocardial injury in early hypertensive heart disease, focusing on segmental parameter differences.MethodsA total of 156 hypertensive patients were enrolled and divided into a left ventricular hypertrophy (LVH) group (n=63) and a non-hypertrophy (Non-LVH) group (n=93) based on the left ventricular mass index (LVMI). All patients underwent CMR examination. Left ventricular function, myocardial strain, global and segmental native T1 values, and extracellular volume (ECV) were obtained using post-processing software. Parameters were compared between the two groups, with special attention to differences among myocardial segments to identify regional characteristics of fibrosis distribution.ResultsCompared with the Non-LVH group, the LVH group showed significantly lower absolute values of global longitudinal strain (GLS; median: −10.80% vs −15.75%), global circumferential strain (GCS), and global radial strain (GRS) (all P <0.05), while global native T1 (median: 1080 ms vs 1036 ms) and ECV (median: 29.8% vs 27.0%) were significantly elevated (P <0.05). Notably, myocardial fibrosis exhibited an apical-predominant distribution pattern, with the most significant parameter differences observed in the apical segments. For instance, in the LVH group, ECV in the apical septal segment (segment 14) was significantly higher [33.50% (30.40, 36.15) vs 26.70% (26.70, 27.90) in Non-LVH, P=0.001], and native T1 in the apical anterior segment (segment 13) was elevated [1105.65 ± 72.31 ms vs 1039.80 ± 47.77 ms, P=0.006], suggesting a possible apical-predominant pattern of myocardial fibrosis.These changes correlated with high diagnostic accuracy for LVH: GLS showed the highest AUC (0.91) in ROC analysis. In the LVH group, global ECV positively correlated with native T1 and LGE positivity, and negatively with GCS and GLS (P <0.05).ConclusionCMR-FT and T1 Mapping techniques can effectively and quantitatively assess myocardial injury and fibrosis in hypertensive patients. Global longitudinal strain (GLS) is a sensitive parameter for diagnosing left ventricular hypertrophy (LVH), and myocardial fibrosis in patients with hypertension-induced LVH exhibits an apical-predominant distribution pattern.This spatial pattern, if validated prospectively, could serve as a potential imaging biomarker for monitoring in hypertensive patients.