Background The management of malignant ventricular tachycardia (VT) in the aftermath of a myocardial infarction is a complex undertaking, particularly in cases accompanied by left ventricular aneurysm (LVA). It is frequently the case that conventional unipolar radiofrequency catheter ablation (RFCA) is inadequate. Case Summary A 50-year-old male patient with a medical history of myocardial infarction presented with recurrent VT due to a LVA. Initial unipolar RFCA proved to be an ineffective treatment. Bipolar RFCA guided by CARTO mapping during coronary artery bypass grafting has been demonstrated to successfully ablate the LVA. Subsequent postoperative follow-up revealed no recurrence of VT and sustained cardiac function over a 2-year period. Discussion Refractory VT due to LVA poses significant treatment challenges. Bipolar RFCA, guided by CARTO mapping, has been shown to offer an effective solution, overcoming the limitations of unipolar RFCA by targeting both epicardial and endocardial arrhythmogenic substrates. This case demonstrates a surgical approach with the potential to yield favorable outcomes.

Accurate detection of multi-shape coronary artery stenoses from X-ray angiography (XRA) sequences plays a crucial role in diagnosing and planning interventions for coronary artery disease. However, vessel overlap, background noise, and nonlinear cardiac motion introduce significant challenges. These factors often result in missed detections, intra-frame class conflict, and temporal category drift, particularly for subtle and morphologically complex stenoses such as focal and bifurcation stenoses. To address these challenges, we propose a Hierarchical Heterogeneous Aggregation Network that effectively integrates both spatial and temporal cues across XRA sequences. The proposed framework incorporates a Channel Importance-guided Fusion module, which aims to enhance the representation of small-stenosis features by dynamically selecting high-importance channels across scales. Furthermore, we introduce a Hierarchical Heterogeneous Aggregator designed to reduce spatial redundancy and explicitly generate discriminative features across frames based on heterogeneous relationships, thereby improving temporal consistency and classification robustness. Existing experiments conducted on two clinical datasets indicate that our method outperforms existing detectors and stenosis methods in terms of detection accuracy and generalization.

Abstract Coronary artery bypass grafting (CABG) is the recommended treatment for severe coronary heart disease; however, restenosis of great saphenous vein grafts continues to limit long-term outcomes because of early thrombosis, mid-term intimal hyperplasia, and late atherosclerosis. To address these sequential pathological processes, this study develops a perivascular drug-loaded microneedle (MN) patch capable of controlled chronological release of tirofiban, rapamycin, and rosuvastatin. The MN patch exhibits uniform conical microneedles (height: 700–800 µm), nanoparticle size of 125 nm, sufficient mechanical strength (1.07 N/needle) for venous intimal penetration, excellent biocompatibility, and no detectable cytotoxicity or hemolysis. In a mouse model of venous graft transplantation, the device significantly reduces early platelet thrombus formation (23.3% to 10%), alleviates mid-term intimal hyperplasia (intimal thickness: 0.84 mm to 0.45 mm at 4 weeks), and improves long-term graft patency with blood flow increasing from 13.1 to 65.8 mL/min at 32 weeks while reducing long-term mortality. Mechanistically, RNA sequencing and functional analyses demonstrate that excessive glycolysis-driven smooth muscle cell proliferation, coupled with abnormal endothelial cell apoptosis, constitutes the core mechanism underlying mid- to long-term restenosis, which the MN device effectively suppresses. This integrated MN patch provides a localised therapeutic strategy for preventing restenosis and improving long-term CABG outcomes. Table of Contents

Objectives The predictive value of transplant hemodynamic parameters for perioperative cardiovascular events after coronary artery bypass grafting is still unclear, especially for patients with diffuse coronary artery disease. The aim of this study is to evaluate the value of TTFM during coronary artery bypass grafting in predicting adverse cardiovascular and cerebrovascular events in patients with diffuse coronary artery disease after coronary artery bypass grafting, as well as the blood flow and PI of transplanted blood vessels required to avoid perioperative myocardial infarction in different transplant blood supply areas. Based on the above results, we will also discuss the surgical efficacy comparison of endarterectomy and SCVBG in revascularization for patients with diffuse lesions of the right coronary artery Methods In this prospective observational single center study, from February 2020 to June 2024, eligible patients who were continuously enrolled in OPCABG used the handheld flow probe during surgery. TTFM is an imaging system that uses the principle of ultrasound to evaluate the blood flow and patency of cardiovascular surgical grafts. CE is an auxiliary method performed simultaneously in CABG for patients with diffuse coronary artery disease. SCVBG is a method to achieve blood flow reconstruction by retrograde perfusion of myocardium through the coronary vein system. The primary end point is perioperative myocardial infarction (PMI) (type 5 MI) after OPCABG. Results MGF-LAD,(26 vs 50) MGF-LCX (24 vs 43) and MGF-RCA (24 vs 39) were significantly higher in patients who did not experience PMI than in those who experienced PMI. The PI-LCX (2.4 vs 2.0) is opposite. MGF-LAD, MGF-LCX, MGF-RCA and PI-LCX were significant predictors of PMI.(Table 1.) When the LIMA-LAD flow rate is greater than 26.5 and the PI is less than 1.75, it is a protective factor for perioperative myocardial infarction. Transplant flow rates with LCX greater than 38 ml/min and PI less than 3.45 may have a protective effect on perioperative posterior wall myocardial infarction. Right coronary artery blood flow velocity greater than 26.5 ml/min has a significant protective effect on posterior wall myocardial infarction. For patients with diffuse lesions of the right coronary artery, SCVBG has better transplant blood flow than CE (43 vs 25.5) and lower PI (1.3 vs 1.85), which can reduce the risk of perioperative arrhythmia and posterior wall myocardial infarction in OPCABG. Conclusions This prospective cohort study suggests that TTFM measurement has predictive value for the occurrence of perioperative myocardial infarction in OPCABG. Among them, LIMA-LAD graft flow greater than 28.5ml/min and PI less than 1.75 are protective factors for perioperative anterior wall myocardial infarction, while sequential bridge LCX graft flow greater than 38ml/min, RCA flow greater than 26.5ml/min, and PI less than 3.45 are protective factors for perioperative lateral posterior wall myocardial infarction.In addition, based on the above results, this study analyzed the surgical procedures of patients with extremely poor vascular conditions in the right coronary artery. The study showed that SCVBG is significantly safer than CE.

Background:Myocardial bridging (MB) is a prevalent coronary anomaly with potential links to major adverse cardiac events. While computed tomography-derived fractional flow reserve (FFRCT) offers a non-invasive functional assessment, current evidence predominantly treats MB as a homogeneous entity, overlooking potential sex differences in hemodynamic impact. Existing studies often fail to distinguish between isolated MB and MB with concomitant atherosclerosis, and rarely employ sex-stratified analyses. This study aimed to noninvasively assess sex-specific differences in FFRCT among patients with MB, with or without atherosclerosis, using an artificial intelligence (AI)-based platform to clarify the clinical implications of these differences. Methods:This retrospective cohort study included 300 left anterior descending artery (LAD)-MB patients, subdivided into an MB group (n=155) and an MB with atherosclerosis (MBLA) group (n=145), along with 104 controls with normal coronary computed tomography angiography (CCTA) findings. Demographic data, clinical symptoms, and risk factors were collected. Morphological parameters of MB were quantitatively analyzed using cardiac function post-processing software, and whole-vessel and local segments (proximal to MB, within MB, and distal to MB) FFRCT values were obtained via an AI-based platform (Shukun-FFRCT). Patients were stratified by FFRCT <0.8, and statistical analyses [t-tests, analysis of variance (ANOVA), Mann-Whitney U tests, and binary logistic regression] were applied to examine sex-based associations with FFRCT abnormalities and influencing factors. Results:(I) Demographic analysis revealed significantly higher proportions of male patients in the MB (52.9%) and MBLA (57.2%) groups compared to controls (24.0%, both P<0.05). (II) Sex-stratified analysis within pathological subgroups showed that in the MB group, females had significantly lower distal FFRCT values (FFR3: median 0.92 vs. 0.95, P=0.006) and higher trans-bridge pressure drop (ΔFFR: 0.08 vs. 0.05, P=0.004) than males. No significant sex-based differences in FFRCT were observed in the MBLA group (all P>0.05). (III) Intra-group comparisons of FFRCT between systolic and diastolic phases showed no significant differences in either case or control groups (all P>0.05). (IV) Binary logistic regression indicated that MB length was an independent risk factor for FFRCT abnormalities in both sexes. Each 1-mm increase in MB length raised the risk of FFRCT abnormality by 5.3% in males [odds ratio (OR) =1.053, 95% confidence interval (CI): 1.004-1.104, P=0.033] and 11.3% in females (OR =1.113, 95% CI: 1.024-1.209, P=0.011). Conclusions:This study innovatively demonstrates through CT-AI quantitative analysis that sex significantly influences FFRCT in LAD-MB patients. Females with isolated MB exhibit more pronounced distal hemodynamic alterations, whereas sex differences diminish when atherosclerosis coexists. Notably, MB length is an independent risk factor for FFRCT abnormalities, with a greater impact observed in females. These findings provide preliminary evidence to inform risk stratification of MB.

Background: Acute kidney injury (AKI) frequently complicates the postoperative course of older patients in surgical intensive care units (ICUs), contributing to increased mortality and prolonged hospital stays. Traditional AKI diagnostic methods, relying on changes in serum creatinine and urine output, often result in delayed detection. Pulse pressure variation (PPV), a dynamic hemodynamic parameter derived from arterial waveform analysis, reflects preload responsiveness and can provide early, complementary information on circulatory status and end-organ perfusion. Although both elevated and diminished PPV levels have been associated with adverse outcomes, the specific nature of the association between early postoperative PPV and AKI risk remains uncertain. This study investigated the relationship between PPV during the first 12 and 24 h after ICU admission and the development of AKI, with a focus on potential nonlinear associations and optimal PPV thresholds. Methods: This retrospective cohort analysis utilized data from the MIMIC-IV and MIMIC-III databases. We included patients aged 60 years and older who underwent cardiothoracic surgery and had available PPV measurements within the first 24 h following ICU admission. The primary dataset was derived from MIMIC-IV, while MIMIC-III served as an external validation cohort. The main outcome was postoperative AKI, as identified by KDIGO criteria. Logistic regression models adjusted for relevant clinical covariates were used to assess associations between PPV at 12 and 24 h (PPV12h and PPV24h) and AKI. Nonlinear associations were examined using restricted cubic spline (RCS) modeling. Discriminative ability was assessed using area under the receiver operating characteristic curve (AUC), with DeLong’s test used to compare model performance. Results: Of the 5,445 patients included, 2,574 (47.3%) developed AKI after surgery. Those with AKI were generally older and had more comorbidities and higher illness severity scores. In multivariable analyses incorporating RCS terms, a U-shaped relationship was identified between PPV12h and AKI (p for nonlinearity = 0.0224). The lowest predicted risk was observed at a PPV12h of 0.144, corresponding to a 39.4% relative reduction in AKI risk. This association was independently validated in a separate cohort (n = 897), where a PPV12h of 0.142 was associated with a 59.8% risk reduction. In contrast, PPV12h provided better predictive value than PPV24h, which showed no significant association with AKI. The inclusion of PPV12h significantly enhanced the discrimination of predictive models. Conclusion: Early postoperative PPV demonstrates a U-shaped correlation with AKI risk in older patients undergoing cardiothoracic surgery, with both low and high values associated with higher incidence. A PPV12h around 0.14 was consistently linked to the lowest risk in both primary and validation cohorts. These findings remained robust after adjusting for multiple confounders. PPV assessed at 24 h, however, showed limited predictive utility. Routine early PPV monitoring may, therefore, serve as a valuable adjunct for perioperative hemodynamic assessment, potentially facilitating timely interventions to mitigate postoperative renal complications.

Laser speckle contrast imaging (LSCI) is a real-time, full-field, non-contact imaging technique widely used for blood flow visualization in biomedical applications. Potentially, LSCI could be applied to monitor the spatiotemporal evolution of the myocardial coronary arteries for improving the surgical quality in coronary artery bypass graft (CABG). The functionality of the myocardial LSCI device has been well demonstrated on the animal hearts by the data post-processing method. While the corresponding real-time LSCI system, which is of great significance to assist the surgeons in making diagnoses during CABG, has not been resolved yet. This paper aims to develop a high-speed laser speckle myocardial blood flow imaging (LSMBFI) system for measuring blood flow perfusion in real time. Through parallel computing and asynchronous programming combined with the speckle contrast-to-blood speed relationship, our LSMBFI system enables to display the blood flow index (BFI) images of 1456 x 1088 pixels with the frame rate of 68 Hz. For smaller region of interest, such as 1000 x 1000 pixels, the displaying framerate could reach up to 120 Hz. For validation, the phantom and the animal experiments are designed. It turns out that our LSMBFI system firstly, to the best of our knowledge, realizes real-time monitoring the spatial and temporal myocardial blood flow perfusion on the beating heart. The results would contribute to improving the surgical quality control in CABG on large animals or human beings and help to the engineering application of the LSMBFI instrument in the future.

The prognostic relevance of Remnant cholesterol (RC) in acute myocardial infarction (AMI), particularly in diabetes mellitus (DM) patients, remains unclarified. This research aimed to explore the interaction between elevated RC and DM on the prognosis of AMI, with the goal of improving risk stratification and guiding intervention strategies. In this retrospective, single-center study, 520 AMI patients were recruited. Basic and follow-up information was acquired, with the primary endpoint being major adverse cardiovascular events (MACE) and the secondary endpoint being cardiac mortality. Multiplicative and additive interactions were assessed to determine the combined impact of RC and DM on prognosis. Analytical methods included Cox regression, Kaplan–Meier survival, and ROC analyses. Over a median follow-up of 45 (42–49) months, 120 (23.08

Coronary artery stenosis is a major pathological basis of coronary artery disease (CAD), and clinical evaluation relies on coronary angiography (CAG) as the gold standard. However, manual assessment suffers from high subjectivity, low efficiency, and poor inter-observer consistency, highlighting the necessity of automated detection methods. Existing studies are mostly “single-task” approaches (segmentation-only or detection-only), which fail to explicitly exploit the complementary information between the two tasks. Moreover, the scarcity of annotated samples limits generalization in complex vascular structures. To address these challenges, we propose a stenosis detection model that integrates a Multi-level Perception Fusion (MPF) framework with Pseudo-Stenosis Pretraining. The MPF framework places a vessel segmentation module before the detection module, providing vascular spatial constraints and structural cues of stenosis. By propagating detection loss to the vessel segmentation module, this module is also enhanced to highlighting the difference of stenotic regions. Meanwhile, Pseudo-Stenosis Pretraining generates morphologically realistic pseudo stenosis samples and adopts a pretraining–fine-tuning scheme to mitigate overfitting in limited data scenarios. Experimental results demonstrate that the proposed model achieves superior performance compared with state-of-the-art methods on both a private dataset and the public ARCADE dataset. On the private dataset, the model achieves F1, recall, and mean Average Precision (mAP) of 68.1, 73.7, and 72.3 in the detection task, outperforming LSKNet, Oriented-RCNN, ReDet, S2ANet, and RetinaNet. On the ARCADE public dataset, the model achieves F1, sensitivity, and area under the curve (AUC) of 60.52, 62.24, and 99.17, surpassing U-Net, PoolNet, and YOLOv8m.

Purpose Sleep disorder is a frequent postoperative complication after total hip arthroplasty (THA). This study aimed to characterize sleep disorder phenotypes, identify associated risk factors, and explore the relationships between sleep disturbance patterns and clinical outcomes in elderly patients aged ≥70 years. Materials and Methods A single-center retrospective analysis included 892 primary THA patients between January 2021 and December 2024. Sleep disorders were assessed via a validated 12-item questionnaire and diagnosed according to the International Classification of Sleep Disorders, 2nd Edition. Visual analog scale (VAS) pain scores and length of hospital stay (LOS) were extracted and stratified by different groups. All patients finished a minimum 6-month postoperative follow-up. Results 78.3% of patients had postoperative sleep disturbances (median 6 weeks, range 4-8 weeks). Primary insomnias (72.1%) dominated, with adjustment sleep disorder (41.5%) most common; secondary insomnias (27.9%) linked to comorbidities (19.7%) and drugs (8.2%). Elderly patients had 83.5% incidence and 3.2-fold higher risk of persistent disturbances versus non-elderly patients ( p <0.001). Patients with sleep maintenance difficulties or non-restorative sleep tended to present with higher VAS ( p <0.001) and longer LOS ( p <0.001) significantly. Discussion Pain (38.6%), psychological stress (29.4%), and intrinsic factors (16.2%) were most commonly associated with sleep disturbances. Elderly patients were more vulnerable to comorbidity-related and environmental sleep disruptors. Differences in clinical indicators were observed between patients receiving personalized perioperative management and those under routine care. Conclusions Adjustment sleep disorder is the most common postoperative sleep phenotype in THA patients. Pain, psychological factors, and intrinsic characteristics are key drivers. In addition, patients with difficulty in staying asleep and non-restorative sleep are associated with higher pain scores and prolonged LOS. Elderly patients are high-risk for persistent sleep disturbances and inferior recovery outcomes. These findings suggest potential directions for patient-centered perioperative management, while relevant associations need further verification.

Vessel segmentation based on X-ray angiography is a common technique for diagnosing and treating coronary artery disease. However, deep learning-based segmentation remains challenging due to the low contrast between vessels and background, as well as the presence of noise and imaging artifacts. In this paper, we propose an intentional semi-supervised learning method based on dual threshold connected component postprocessing. First, the postprocessing method increases the sensitivity of the segmentation model and denoises the segmentation masks. Second, we leverage a large number of unannotated angiograms, whose pseudo-labels are generated by applying the postprocessing method to the network predictions. By training the network with these postprocessed pseudo labels in a semi-supervised manner, the essential prior knowledge of the postprocessing method is intentionally transferred to the network. Experiments on three different datasets reveal that, the model trained with intentional semi-supervised learning has higher performance when applying the postprocessing method again. With the proposed methods, the dice scores of different vessel segmentation models are increased on all three datasets.

BackgroundThe presence of a left atrial appendage (LAA) thrombus is traditionally considered a contraindication to epicardial left atrial appendage closure (LAAC) because of the risk of periprocedural embolization. This presents a significant challenge for atrial fibrillation (AF) patients with a high bleeding risk who are intolerant to long-term anticoagulant treatment. The safety and outcomes of epicardial LAAC in patients with a preexisting LAA thrombus remain poorly defined.MethodsThis retrospective cohort study included 108 AF patients who underwent epicardial LAAC at a single center. Patients were stratified into two groups on the basis of preoperative imaging: the Thrombus Group (n = 11) and the No-Thrombus Group (n = 97). Intraoperative management, perioperative complications, and long-term clinical outcomes (cerebrovascular events and all-cause mortality) were compared between the groups. An imaging-based classification of thrombus morphology (Types I-III) was proposed for risk stratification.ResultsNo intraoperative strokes or deaths occurred in either group. Early postoperative complication rates were low and not significantly different between groups. During follow-up, the rates of thromboembolic events (1.0 vs. 2.3 per 100 patient-years) and all-cause mortality (0.3 vs. 0.0 per 100 patient-years) were comparable between the No-Thrombus and Thrombus groups, with no statistically significant differences. Thrombi confined to the LAA tip (Type I) were associated with favorable outcomes.ConclusionEpicardial LAAC appears to be a feasible and safe alternative for stroke prevention in some AF patients with LAA thrombi who are unsuitable for anticoagulation therapy, as it does not increase perioperative risk or compromise long-term treatment efficacy.

Background: Coronary artery disease (CAD) remains the leading cause of mortality worldwide. Coronary digital subtraction angiography (DSA) is the gold standard for evaluating coronary lesion location, extent, and severity, and it serves as the primary basis for informing decisions related to revascularization. However, the interpretation of DSA in complex lesions is often time-consuming and subject to interobserver variability. This study aims to develop and validate a multisource cue fusion-based method for precise localization of coronary artery stenosis in digital subtraction angiography. Methods: In this study, a detection network was developed for accurately localizing stenosis in key frames of coronary DSA by integrating multisource cues. Specifically, the vessel segmentation provides spatial contour cues, while adjacent frames offer dynamic cues. To effectively combine these, a cross-cue attention-based fusion module was designed, which enhances target frame representation by capturing nonlocal spatial dependencies. Furthermore, a distance-based penalty from the coronary ostium was incorporated into the loss function to improve the model's sensitivity to localization errors of proximal stenosis. Results: The proposed method achieved a precision of 87.90%, a recall of 65.78%, an F1-score of 74.99%, a mean average precision at 0.5 intersection of union (IoU) threshold (mAP@0.5) of 78.46%, and a mAP across multiple IoU thresholds from 0.5 to 0.95 with a step size of 0.5v (mAP@0.5-0.95) of 60.37%, outperforming YOLOv5, YOLOv8, and YOLOv12 on all metrics. Ablation studies further demonstrated that the total loss led to superior performance, with mAP@0.5-0.95 increasing to 60.37%, in contrast to 56.23% with complete IoU loss and 58.01% with distance-weighted loss. Conclusions: This study addresses the critical need for precise identification and localization of coronary artery stenosis in the assessment of CAD by proposing a coronary artery stenosis detection method for DSA that integrates multiple sources of information. This method effectively combines the structural information from the target frame with the dynamic temporal sequence data from adjacent frames, overcoming the limitations of single-frame information and enhancing the accuracy of stenosis localization.

Background This study aimed to investigate the effects of prior percutaneous coronary intervention (PCI) on intraoperative hemodynamic parameters and perioperative outcomes in patients undergoing coronary artery bypass grafting (CABG). Methods This was a prospective, observational study. Baseline and perioperative data, including patient demographics (age and sex), myocardial injury markers, mean graft flow, and pulsatility index of each transplanted vessel, were collected during the surgical procedure. A comprehensive analysis was conducted to evaluate the influence of prior PCI history on baseline characteristics, intraoperative parameters, and the incidence of perioperative complications in patients undergoing CABG. Logistic and linear regression models were used to assess the association between prior PCI and clinical outcomes. Results Patients with a history of PCI demonstrated improved intraoperative hemodynamic parameters. Following adjustment for age, sex, and body mass index (BMI), multivariate logistic regression analysis revealed that patients with prior PCI had a lower risk of postoperative myocardial injury (PMI) (95% confidence interval [CI], 0.06–0.63, P = 0.006), despite presenting with potentially adverse factors such as higher body weight and elevated low-density lipoprotein (LDL) levels. Conclusion A history of PCI may contribute to more complete myocardial revascularization, thereby reducing the risk of myocardial injury and impaired cardiac function during CABG. The hemodynamic performance of grafts is influenced by factors such as prior PCI history, preoperative body weight, LDL levels, and history of stroke. Comprehensive preoperative evaluation and appropriate selection of surgical timing and strategy can further minimize the occurrence of adverse events during CABG.

Early thrombosis following coronary artery bypass grafting (CABG) surgery leads to perioperative myocardial infarction, which causes difficulties for clinicians and patients. Moreover, once perioperative myocardial infarction occurs, the mortality rate is extremely high. In recent years, microneedle (MN) drug delivery systems have become a research hotspot with broad clinical application prospects. These systems are capable of achieving sustained, safe, and painless local drug release. In cardiovascular applications, MNs maximize local anticoagulant effects, inhibit endometrial hyperplasia, and reduce systemic side effects. We speculate that a MN drug delivery system can be used to target transplanted veins to inhibit their thrombosis and reduce the incidence of perioperative myocardial infarction after CABG surgery. Therefore, this study developed a hyaluronic acid MN patch loaded with tirofiban and conducted preliminary physicochemical tests. The safety, efficacy, biocompatibility, and targeting of the MN system were evaluated usingin vitroandin vivoexperiments using a jugular vein transplantation model. The results indicate that the MN system has excellent physical properties, safety, effectiveness, biocompatibility, and strong targeting, which can effectively inhibit early local thrombus formation. In addition, the observation of early postoperative endometrial hyperplasia activation provides a foundation for future research.

Significance:Myocardial oxygen metabolism is a key focus of cardiac surgery. It serves as important evidence for surgeons to evaluate surgical quality and surgical plans. However, current clinical methods lack the capability to directly monitor dynamic changes in myocardial metabolism during surgery. Photoacoustic imaging (PAI), a biomedical optical imaging modality, offers real-time assessment of blood oxygen saturation. By visualizing oxygen saturation levels in both blood and muscle tissue, PAI provides a means to infer myocardial metabolic status intraoperatively. Aim:We use PAI to observe the differences between infarcted myocardium and normal cardiac muscle and to explore the feasibility of using PAI to monitor myocardial metabolism levels during cardiac surgery. Approach:Ten rabbits were randomly divided into experimental and control groups. The animals in the experimental group underwent thoracotomy followed by left anterior descending coronary artery ligation, whereas those in the control group received thoracotomy only. PAI was performed both at the beginning and before the end of the surgical procedure. The PAI results were compared between the two groups to analyze the relationship between myocardial PAI signal changes and oxygen metabolism levels. Results:Following coronary ligation, the experimental group exhibited significant ST-segment elevation on electrocardiography, whereas no notable changes were observed in controls. PAI demonstrated: baseline myocardial oxygen saturation ( SmO 2 ) ranged from 45% to 72% across all rabbits. Ligation-induced ischemia sharply reduced SmO 2 to 1% to 19% in experimental animals. Control animals maintained stable SmO 2 levels throughout the procedure. Histopathological examination confirmed extensive myocardial necrosis in the apical region of ligated rabbits, consistent with the observed functional and metabolic alterations. Conclusions:PAI can detect myocardial oxygen saturation in real-time during surgery and determine the occurrence of myocardial ischemia and changes in oxygen metabolism levels based on differences in oxygen saturation.

Transplant vein restenosis is the main complication affecting the long-term graft patency after coronary artery bypass grafting, mainly caused by VSMC proliferation and migration (initiating factors), leading to intimal hyperplasia and restenosis. Transplant vein restenosis has seriously affected the surgical efficacy of CABG, and the degree of transplant vein restenosis determines the patient's survival time. Therefore, a solution to this problem is urgent. Rapamycin is a cell cycle drug that can inhibit VSMC proliferation and migration but its systemic toxicity is high. In recent years, microneedle drug delivery systems have become a research hotspot with broad clinical application prospects. These systems are capable of achieving sustained, safe, and painless local drug release. In cardiovascular applications, MNs can maximize local drug effects and reduce systemic side effects. We speculate that the MN drug delivery system can be used to target transplanted veins, suppress restenosis by inhibiting SMC proliferation, reduce the incidence of restenosis after coronary artery bypass grafting, and delay the occurrence of restenosis. Therefore, this study developed a hyaluronic acid MN patch loaded with rapamycin and conducted preliminary physicochemical experiments. The study was conducted in in vitro and in vivo experiments using a jugular vein transplantation model to evaluate the safety, efficacy, biocompatibility, and targeting of the MN system. The results indicate that the MN system has excellent physical properties, safety, effectiveness, biocompatibility, and strong targeting, which can act on HIF-1 and effectively inhibit the proliferation, migration, and intimal hyperplasia of SMC. This provides a foundation for future research on inhibiting CABG restenosis throughout the entire process to ensure the patency of transplanted blood vessels.

Blood-contacting medical devices can easily trigger immune responses, leading to thrombosis and hyperblastosis. Constructing microtexture that provides efficient antithrombotic and rapid reendothelialization performance on complex curved surfaces remains a pressing challenge. In this work, we present a robust and regular micronano binary texture on the titanium surface, characterized by exceptional mechanical strength and precisely controlled wettability to achieve excellent hemocompatibility. Systematic in vitro and in vivo investigations confirmed that the micronano binary texture with superhydrophilic modification effectively suppressed the adhesion and activation of plasma proteins and blood cells, thereby mitigating the subsequent coagulation cascade and thrombosis. Meanwhile, the modified surface significantly upregulated the gene expression involving cell-matrix adhesion, growth factor synthesis, and calcium-mediated cytoskeleton remodeling and then accelerated the formation of a healthy and stable endothelial cell layer. This enhancement of re-endothelialization was not observed with pure titanium and superhydrophobic surfaces. Hence, superhydrophilic micronano binary texture not only significantly inhibits thrombosis but also selectively enhances the integrity and viability of the endothelial cell layer, making it a promising strategy for improving the long-term anticoagulation performance of vascular implants.

Laser speckle contrast imaging (LSCI) is a real-time, non-invasive imaging technique widely used for visualizing blood flow in biomedical applications. Likely, LSCI method can be applied to the myocardial coronary artery to monitor the evolution of blood flow on spatial and temporal scales, which is of large-size inner diameter, higher flow rate, and has thicker vascular walls. In this paper, we aim to measure wide-range blood flow rate linearly under static scattering noise. We elaborate on the differences between temporal and spatial static scattering parameter that are typically ignored but can result in inaccurate measurements of blood flow through phantom experiments. It is the first time, to our best of knowledge, that the maximum linear range can be measured up to 616 mm/s with 20 Hz sampling frequency. When the blood flow is covered by cardiac vascular tissue, the maximum linear blood flow range can be up to 92.4 mm/s with 100 Hz sampling frequency. Besides, we compared uniform light with ring-shaped light and demonstrated that the latter can increase penetration depth, thereby extending the linear range and reducing oscillations in the curve. Those results will greatly lower the expense of LSCI device while improving performance, and benefit future big animal clinical medical research, especially in monitoring the spatiotemporal evolution of coronary arteries in coronary artery bypass grafting (CABG) surgery.