BACKGROUND:Arthroscopic anchor repair has become the main treatment method for rotator cuff tears at present.Among them,the insertion status of the anchor is a key factor in the success or failure of the operation.However,currently,the impact of the insertion depth of the anchor on the stress of the bone tunnel and the anchor under different bone density conditions remains unclear.OBJECTIVE:To explore the stress distribution of the bone tunnel and the anchor when the insertion depth of the anchor varies under different bone density conditions by using three-dimensional finite element analysis technology.METHODS:The CT image data of the humerus of volunteers were collected,and the models of the humerus and the anchor were constructed by using Mimics,3-Matic,and Solidworks software.In 3-Matic,holes with distances of 0,2,4,6,and 8 mm from the surface of the humerus were respectively created at the same position of the humerus and assembled with the anchor.In Mimics,values were assigned based on the CT gray value to obtain a model with normal bone mass(T value ≥-1.0).The parameters were changed to construct models with reduced bone mass(-2.5＜T value＜-1.0)and osteoporosis(T value＜-2.5).In each model,a 70 N pulling force was applied to the anchor along the direction tangent to the inner edge of the bone tunnel.The stress distribution and magnitude of the bone tunnel and the anchor when inserted at different depths under different bone density conditions were observed.RESULTS AND CONCLUSION:(1)When the insertion depth was the same,as the bone density decreased,the maximum equivalent stress of the anchor increased,while the maximum equivalent stress of the bone tunnel decreased.(2)When the bone density was the same,as the insertion depth of the anchor increased,the maximum equivalent stress of the anchor decreased.When the insertion depth was 4 mm,the stress of the bone tunnel was the smallest and the distribution was relatively uniform.The stress of the anchor was mainly distributed around the lower anchor hole and the proximal thread,and the stress of the bone tunnel was mainly at the part in contact with the proximal thread.The increase in the insertion depth would change the uniformity and pattern of the stress distribution,while the bone density had a relatively small impact on the stress distribution pattern.(3)It is concluded that the bone density of the humerus is crucial for the anchor repair of rotator cuff tears.It is recommended that clinicians measure the bone density of the greater tuberosity of the humerus before the operation.Excessive insertion depth of the anchor does not significantly increase its stability.Clinicians can conduct personalized preoperative assessments by using the finite element analysis method in combination with the actual situation of patients to achieve the best surgical results.

BACKGROUND:Arthroscopic anchor repair has become the main treatment method for rotator cuff tears at present.Among them,the insertion status of the anchor is a key factor in the success or failure of the operation.However,currently,the impact of the insertion depth of the anchor on the stress of the bone tunnel and the anchor under different bone density conditions remains unclear.OBJECTIVE:To explore the stress distribution of the bone tunnel and the anchor when the insertion depth of the anchor varies under different bone density conditions by using three-dimensional finite element analysis technology.METHODS:The CT image data of the humerus of volunteers were collected,and the models of the humerus and the anchor were constructed by using Mimics,3-Matic,and Solidworks software.In 3-Matic,holes with distances of 0,2,4,6,and 8 mm from the surface of the humerus were respectively created at the same position of the humerus and assembled with the anchor.In Mimics,values were assigned based on the CT gray value to obtain a model with normal bone mass(T value ≥-1.0).The parameters were changed to construct models with reduced bone mass(-2.5＜T value＜-1.0)and osteoporosis(T value＜-2.5).In each model,a 70 N pulling force was applied to the anchor along the direction tangent to the inner edge of the bone tunnel.The stress distribution and magnitude of the bone tunnel and the anchor when inserted at different depths under different bone density conditions were observed.RESULTS AND CONCLUSION:(1)When the insertion depth was the same,as the bone density decreased,the maximum equivalent stress of the anchor increased,while the maximum equivalent stress of the bone tunnel decreased.(2)When the bone density was the same,as the insertion depth of the anchor increased,the maximum equivalent stress of the anchor decreased.When the insertion depth was 4 mm,the stress of the bone tunnel was the smallest and the distribution was relatively uniform.The stress of the anchor was mainly distributed around the lower anchor hole and the proximal thread,and the stress of the bone tunnel was mainly at the part in contact with the proximal thread.The increase in the insertion depth would change the uniformity and pattern of the stress distribution,while the bone density had a relatively small impact on the stress distribution pattern.(3)It is concluded that the bone density of the humerus is crucial for the anchor repair of rotator cuff tears.It is recommended that clinicians measure the bone density of the greater tuberosity of the humerus before the operation.Excessive insertion depth of the anchor does not significantly increase its stability.Clinicians can conduct personalized preoperative assessments by using the finite element analysis method in combination with the actual situation of patients to achieve the best surgical results.

Mesenchymal stem cells (MSCs) have been widely used in the treatment of various autoimmune and inflammation-related diseases due to their potent immunomodulatory properties. Several studies have demonstrated that MSC-mediated immunomodulation is complex and bidirectional, with the in vivo microenvironment influencing the direction of this modulation. Indoleamine-2,3-dioxygenase (IDO), an immunosuppressive factor, has been identified as a key "switch" in the immunomodulatory role of MSCs. In this review, we explore how IDO functions as a critical regulator of MSC immunoregulatory plasticity. We delve into the mechanisms by which changes in IDO expression affect the function of various immune cells, summarize relevant research and clinical advances regarding the role of IDO expression in MSC-based therapies for various diseases, and discuss potential therapeutic strategies that target IDO to enhance the stability of MSC therapeutic effects. This provides a theoretical foundation for optimizing MSCs as safer and more effective clinical therapeutic agents.

Objective:To comprehensively evaluate the changes in pulmonary artery hemodynamics in patients with repaired tetralogy of Fallot (rTOF) using four-dimensional flow (4D Flow) MRI, and to explore the value of viscous energy loss (EL) as an evaluation parameter of the right heart in patients with rTOF.Methods:A total of 30 rTOF patients who were prospectively admitted at Fuwai Hospital between October 2017 and November 2019, and 19 healthy controls who were prospectively recruited on March 2023, were enrolled in this study. All participants underwent a comprehensive 4D Flow MRI evaluation, and indicators of comparison between the two groups including quantitative flow analysis, wall shear stress (WSS) assessment, and EL evaluation in four planes: the right ventricular outflow tract (RVOT), main pulmonary artery (MPA), right pulmonary artery (RPA), and left pulmonary artery (LPA). The correlation between EL and traditional right ventricular (RV) function parameters, as well as WSS, was analyzed.Results:The RV function was generally decreased in rTOF patients, with an RV ejection fraction of 41.42 (35.85, 43.33) %. Compared with healthy controls, the volumes of backward flow, peak velocities, and both axial and circumferential WSS at the RVOT, MPA, RPA, and LPA were significantly increased in rTOF patients (all P<0.05). The EL in the pulmonary artery was extremely low in healthy controls, with the maximum EL values for the MPA-RPA and MPA-LPA segments during cardiac cycle being 0.51 (0.42, 0.73) and 0.68 (0.40, 0.94) mW, respectively. However, in rTOF patients, the EL values were as high as 63.63 (35.35, 82.15) and 56.41 (34.96, 88.76) mW, respectively. There was a significant moderate negative correlation between EL and RV ejection fraction, and a moderate to high positive correlation between EL with RV volume index, regurgitation fraction, as well as peak velocities (all P<0.05). Additionally, there was a significant positive correlation between EL and axial and circumferential WSS, with the correlation coefficients at MPA ranging from 0.67 to 0.88 (all P<0.05). Conclusions:Disordered flow in the pulmonary artery is common in patients with rTOF and should not be overlooked. The extensive viscous EL is closely associated with traditional RV function parameters and WSS. EL is expected to become an crucial parameter for evaluating right heart function in rTOF patients.

The American College of Cardiology/American Heart Association,in collaboration with other societies/associations,has issued"the 2023 Multimodality Appropriate Use Criteria for the Detection and Risk Assessment of Chronic Coronary Disease".This guideline aims to provide appropriate use criteria for the use of functional stress testing and anatomical diagnostic methods in the evaluation of known or suspected chronic coronary disease.The updated content of the guideline is of significant importance for guiding clinical practitioners in China to apply cardiovascular imaging techniques rationally,to detect chronic coronary disease patients at an early stage,and to conduct risk assessments accurately,thereby ensuring high-quality clinical management of patients with chronic coronary disease.

Heart failure(HF)is the end-stage of various cardiovascular diseases,and its global prevalence is steadily increasing,placing a significant burden on both patients and healthcare systems.As the challenges in diagnosing and treating HF grow,early precise diagnosis,individualized treatment,and monitoring disease progression have become critical issues.The advancement of non-invasive imaging technologies,particularly in ultrasound,computed tomography(CT),nuclear medicine,and magnetic resonance imaging,provides new solutions to address these challenges.Therefore,this special issue focuses on the application of non-invasive imaging in HF,aiming to offer more accurate diagnostic and therapeutic support to clinical practice.This issue highlights the latest advancements in ultrasound,CT,nuclear medicine,and magnetic resonance imaging in HF diagnosis and treatment,emphasizing the unique contributions of each imaging modality in addressing key issues in HF.These studies demonstrate the critical role of non-invasive imaging in early diagnosis,functional assessment,and risk stratification in HF,providing innovative ideas and methods for clinical practice.Although significant progress has been made in imaging technologies for HF management,challenges such as standardization and data integration remain.In the future,the combination of artificial intelligence and multimodal imaging will further enhance the accuracy and efficiency of HF management,while promoting the widespread application of imaging in precision medicine for HF.

Objectives:To investigate the clinical value of cardiac magnetic resonance imaging(CMR)feature-tracking strain analysis in risk stratification of diabetic heart failure with preserved ejection fraction(HFpEF).Methods:In this retrospective study,a total of 215 patients with diabetic HFpEF who underwent CMR at Chinese Academy of Medical Sciences Fuwai Hospital from January 2012 to December 2018 were included.Myocardial strain parameters were calculated using CMR feature-tracking technology.Patients were followed up by medical records or telephone calls.Composite endpoint event,all-cause death or heart failure hospitalization during follow-up were recorded.Patients were divided into event group and event-free group.Univariable and multivariable Cox proportional hazard regression analyses were performed to determine the risk factors for the outcomes in diabetic HFpEF.The effects of hypertension and obesity on the prognosis of diabetic HFpEF patients and whether they affect the prognostic value of CMR feature-tracking strain analysis were also analyzed.Results:During a follow-up of(7.1±1.8)years,93(43.3%)patients had endpoint events(event group),including 28 all-cause deaths and 65 heart failure hospitalization.Compared with the event-free group(n=122),patients in the event group had significantly lower left ventricular ejection fraction,higher prevalence and extent of late gadolinium enhancement,and significantly reduced global longitudinal strain(GLS),global circumferential strain,global radial strain,and global systolic longitudinal strain rate(all P<0.05).The absolute GLS value was significantly lower in event group than in event-free group,regardless of the presence of hypertension and obesity.Multivariate Cox regression analysis showed that estimated glomerular filtration rate(HR=0.983,95%CI:0.972-0.993,P=0.001),left atrial volume index(HR=1.015,95%CI:1.005-1.026,P=0.004),and GLS(HR=1.142,95%CI:1.060-1.231,P<0.001)were independent risk factors for adverse cardiovascular events in diabetic HFpEF patients.However,adjusted N-terminal pro-brain natriuretic peptide was not an independent prognostic factor.The cut-offvalue of GLS to predict outcome was-14.09%from ROC curve analysis.The Kaplan-Meier curve showed that in patients with and without hypertension and obesity,patients with the GLS>-14.09%had lower event-free survival compared to patients with GLS≤-14.09%(all P<0.05),and the ability of GLS to predict adverse outcomes was not affected by hypertension and obesity.Conclusions:GLS obtained by CMR feature-tracking strain analysis is an independent predictor of adverse outcomes in diabetic HFpEF,and its ability to predict adverse outcomes is independent of hypertension and obesity.

Objective:To investigate the clinical characteristics and cardiac magnetic resonance (CMR) features of cardiac sarcoidosis (CS).Methods:This retrospective study included 8 consecutive patients with pathologically confirmed CS by endomyocardial biopsy from Fuwai Hospital, Chinese Academy of Medical Sciences, between January 2012 and September 2024. All patients underwent comprehensive CMR examinations including cine imaging and late gadolinium enhancement (LGE) imaging. Clinical data, including electrocardiographic findings, were collected. CMR phenotyping was performed based on imaging characteristics, and cardiac structure and function parameters were evaluated. LGE analysis was conducted using the American Heart Association 17-segment model to assess the distribution patterns and involvement sites.Results:The most common clinical symptoms were chest tightness (4 patients), palpitations (4 patients), and shortness of breath (6 patients). Electrocardiographic abnormalities included atrioventricular block in 4 patients, right bundle branch block in 2 patients, left bundle branch block in 2 patients, frequent premature ventricular contractions in 4 patients, and non-sustained ventricular tachycardia in 5 patients. CMR phenotyping revealed hypertrophic cardiomyopathy pattern in 3 patients, with 2 patients maintaining normal biventricular function and 1 patient showing significantly reduced biventricular systolic function. Dilated cardiomyopathy pattern was identified in 4 patients, all demonstrating significantly impaired biventricular systolic function. One patient exhibited another phenotype with preserved biventricular systolic function. LGE analysis demonstrated that the anterior wall and anterior septum (segments 1, 2, 7, 8) were the most frequently involved regions, followed by the lateral and inferior walls (segments 5, 6, 11, 12). Subepicardial involvement was the predominant pattern of myocardial enhancement.Conclusions:Cardiac sarcoidosis exhibits diverse clinical manifestations and heterogeneous imaging characteristics. CMR not only provides a comprehensive assessment of cardiac structure and function but also reveals distinctive myocardial tissue characteristics, particularly the extent and distribution patterns of LGE involvement. These findings have significant reference value for early identification of CS and differential diagnosis from other cardiomyopathies.

Objective:To explore the feasibility and effectiveness of full free-breathing cardiac magnetic resonance (CMR) in clinical practice.Methods:The study prospectively included patients who underwent full free-breathing CMR and traditional breath-holding cine imaging between June 1 and June 30, 2024. An analysis and comparison were conducted on the image acquisition time, image quality, and left ventricular function parameters under two scanning methods, including left ventricular ejection fraction (LVEF), left ventricular cardiac output (LVCO),left ventricular end diastolic volume (LVEDV), left ventricular end diastolic volume index (LVEDVI), left ventricular end systolic volume (LVESV), left ventricular end systolic volume index (LVESVI), left ventricular stroke volume (LVSV), and left ventricular mass (LVM). In addition, the study conducted both quantitative and qualitative analyses of other sequences in full free-breathing CMR, including T 1 mapping, T 2 mapping, flow imaging, and late gadolinium enhancement (LGE). Group comparisons were performed using the Wilcoxon signed-rank test or paired t-test. Consistency assessments included Bland-Altman analysis, intraclass correlation coefficient ( ICC), and linear regression analysis. Results:Totally, 150 patients were recruited into the study. The average acquisition time of full free-breathing CMR was (22.1±3.1) min, with an average short axis cine sequence examination time of (2.7±0.4) min; The average acquisition time of short axis images in a breath-holding state was (4.9±1.4) min, which was significantly longer than the cine scan in the free-breathing state ( P0.001). The cine and LGE images quality scores obtained from full free-breathing CMR were 4 (4, 4) points and 5 (4, 5) points, respectively, while the cine image quality score obtained in a breath-holding state was 5 (4, 5) points. Compared with traditional breath-hold CMR, free-breathing CMR measurements showed slightly higher LVESV, and LVESVI, while LVEDV, LVEDVI, LVSV, LVCO, LVEF, and LVM were slightly lower, except for LVSV and LVCO, which showed no statistically significant difference, the differences in other cardiac function parameters were statistically significant ( P0.05). However, the two methods demonstrated good consistency( ICC0.947) and correlation (0.808 r0.993, P0.001). The Bland-Altman analysis showed that the bias for all cardiac function parameters was within 8.0%. The Native T 1 and T 2 values for free-breathing CMR were (1 277.5±57.0) ms and 40.1 (38.5, 41.4) ms, respectively, and the results of flow imaging and echocardiography were basically consistent. Conclusions:Free-breathing CMR is feasible and effective in clinical practice, showing a high level of consistency with left ventricular functional parameters obtained from traditional breath-hold scanning. It significantly shortens examination time and holds great clinical value for the promotion and widespread use of CMR.

Objective To observe the value of AcoStream thrombus aspiration catheter for treating intermediate-high risk acute pulmonary embolism(APE).Methods Twenty-six patients with intermediate-high risk APE who underwent treatment with AcoStream thrombus aspiration catheter were retrospectively collected.The immediate technical success rate,procedure success rate and thrombus clearance rate of target vessels were recorded,as well as clinical success rate and complications in perioperative period and the recurrence of pulmonary embolism(PE)during follow-up.Results Among 26 patients with intermediate-high risk APE,the immediate technical success rate was 100%(26/26),the procedure success rate was 92.31%(24/26),and the immediate thrombus clearance rate of target vessels was 63.37%as median,including 16 cases(16/26,61.54%)achieved thrombus clearance rate grade Ⅱ or above.The perioperative period clinical success rate of treating intermediate-high risk APE was 96.15%(25/26).Two patients experienced transient arrhythmia and other 2 patients experienced worsening transient chest tightness during the procedure,and 1 case developed hematoma at the puncture site after treatment.During follow-up,no recurrence of symptomatic PE was observed.Conclusion AcoStream thrombus aspiration catheter was safe and effective for treating intermediate-high risk APE,worthy clinical promotion and application.