To visualize and quantify the hemodynamics in the aortic arch in normal individuals, we used velocity distribution, retrograde flow, vortex formation, and mean energy loss (mEL) at different cardiac cycles in our study. We performed Vector flow mapping (VFM) analysis by using echocardiography in 87 healthy volunteers. The results showed that ① in different sections of the aortic arch, a skewed peak flow velocity (Vp) always appeared in the period of rapid ejection but in different distribution. The systolic flow in the entire aortic arch rose rapidly from near-zero at the point of iso-volumetric contraction to the peak velocity at the period of rapid ejection, and then decreased gradually; ② In the period of iso-volumetric relaxation, retrograde flow and vortex were observed in all subjects in the inner wall of the entire aortic arch; and ③ The change rule of mEL in the entire aortic arch was similar to that of flow velocity. VFM can provide insights into the intra-aortic arch flow patterns, and offer essential fundamentals about flow features associated with common aortic diseases.
Quantitative measurement of strain distribution of arterial vessel walls due to pulsatile blood flow within the vascular lumen is valuable for evaluating the elasticity of arterial wall and predicting the evolution of plaques. The present paper shows that the three-dimensional (3D) strain distribution are estimated through uni-directional coupling for 3D vessel and blood models reconstructed from intravascular ultrasound (IVUS) images with the computational fluid dynamics (CFD) numerical simulation technique. The morphology of vessel wall and plaques as well as strain distribution can be visually displayed with pseudo-color coding.
Surgical intervention for chronic thoracoabdominal aortic dissecting aneurysms (cTAADA) is regarded as one of the most challenging procedures in the field of vascular surgery. For nearly six decades, open repair predominantly utilizing prosthetic grafts has been the treatment of choice for cTAADA. With advances in minimally invasive endovascular technologies, two novel surgical approaches have emerged: total endovascular stent-graft repair and hybrid procedures combining retrograde debranching of visceral arteries with endovascular stent-graft repair (abbreviated as hybrid procedure). Although total endovascular stent-graft repair offers reduced trauma and quicker recovery, limitations persist in clinical application due to hostile anatomical requirements of the aorta, high costs, and the lack of universally available stent-graft products. Hybrid repair, integrating the minimally invasive ethos of endovascular repair with visceral artery debranching techniques, has increasingly become a significant surgical modality for managing thoracoabdominal aneurysms, especially in cases unsuitable for open surgery or total endovascular treatment due to anatomical constraints such as aortic tortuosity or narrow true lumens in dissections. Recent enhancements in hybrid surgical approaches include ongoing optimization of visceral artery reconstruction strategies based on hemodynamic analyses, and exploration of the comparative benefits of staged versus concurrent surgical interventions.
Post-implantation early right heart failure (RHF) following left ventricular assist device (LVAD) placement is characterized by a high incidence and poor prognosis. Current risk stratification models primarily rely on hemodynamic, imaging, and organ function parameters obtained under resting conditions, but their external validation and generalizability are limited. In contrast, stress testing, which increases cardiac load through vasodilators or exercise, offers incremental value in predicting postoperative RHF. This review centers on a dual-state assessment (rest and stress), summarizing the strengths and limitations of indices such as the ratio of central venous pressure to pulmonary artery wedge pressure (CVP/PAWP) and the pulmonary artery pulsatility index (PAPi). It further compares established risk models like CRITT score and European Registry for Patients with Mechanical Circulatory Support (EUROMACS), demonstrating the augmented predictive power of pharmacological or exercise stress testing. A stratified strategy is proposed, involving initial screening with static parameters followed by confirmatory stress testing. Furthermore, an integrated approach of incorporating stress-derived parameters into these models is suggested. Finally, the paper advocates for prospective validation studies in the cohort of patients receiving domestically-produced LVAD, with the aim of establishing a systematic framework to guide perioperative decision-making and enhance individualized prediction.
Intravascular optical coherence tomography (IVOCT) has emerged as a high-resolution and minimal-invasive imaging technique that provides high-speed visualization of coronary arterial vessel walls and clearly displays the vessel lumen and lesions under the intima. However, morphological gray-scale images cannot provide enough information about the tissue components to accurately characterize the plaque tissues including calcified, fibrous, lipidic and mixed plaques. Quantitative IVOCT (qIVOCT) is necessary to provide the physiological contrast mechanisms and obtain the characteristic parameters of tissues with clinical diagnostic value. In this paper, the progress of qIVOCT is reviewed. The current methods for quantitatively measuring optical, elastic and hemodynamic parameters of vessel wall and plaque tissues using IVOCT gray-scale images and raw backscattered signals are introduced and potential development is forecast.
Objective To study the hemodynamic characteristics of concealed perforator flap in mini-pigs by ultrasonic Doppler technique. Methods Seven 7-month-old mini-pigs, weighing 20-25 kg, were included in the study. The saphenous artery perforator flap (group A, n=4), saphenous artery concealed perforator flap (group B, n=5), and saphenous artery concealed perforator flap combined with sarcolemma (group C, n=5) models were established randomly on both hind limbs of pigs. The pigs and flap survival conditions were observed after operation. The percentage of flap survival area was calculated by Photoshop CS5 software at 5 days after operation. Ultrasonic Doppler technique was performed on the flaps before operation and at immediate, 3 days, and 5 days after operation to record the hemodynamic changes of the flaps. The hemodynamic indicators of saphenous artery (inner diameter, peak systoli velocity, resistance index, and blood flow) and saphenous vein (inner diameter, maximum velocity, and blood flow) were recorded. Results At 1 day after operation, 1 pig died of infection, and the rest survived until the experiment was completed. Finally, the 3 flaps of group A, 4 of group B, and 5 of group C were included in the study. The flaps of the 3 groups all showed swelling after operation, which was most significant at 3 days. At 3 days after operation, the flaps in group B showed partial bruising and necrosis. At 5 days after operation, the flaps in groups A and C were basically alive, and the necrosis area of flap in group B increased further. The percentage of flap survival area in groups A, B, and C were 99.7%±0.5%, 74.8%±26.4%, and 100%, respectively. The percentage of flap was significantly lower in group B than in groups A and C (P<0.05). There was no significant difference between groups A and C (P>0.05). There were significant differences in the hemodynamic indicators of saphenous artery and vein between different time points in 3 groups (P<0.05). There was no significant difference in each indicator between groups at each time point (P>0.05). Conclusion Both the saphenous artery concealed perforator flap and the flap combined with sarcolemma have stable blood flow, but the survival area of the latter was better than the former.
Objective To identify potential hub genes and key pathways in the early period of septic shock via bioinformatics analysis. MethodsThe gene expression profile GSE110487 dataset was downloaded from the Gene Expression Omnibus database. Differentially expressed genes were identified by using DESeq2 package of R project. Then Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses were constructed to investigated pathways and biological processes using clusterProfiler package. Subsequently, protein-protein interaction (PPI) network was mapped using ggnetwork package and the molecular complex detection (MCODE) analysis was implemented to further investigate the interactions of differentially expressed genes using Cytoscape software. Results A total of 468 differentially expressed genes were identified in septic shock patients with different responses who accepted early supportive hemodynamic therapy, including 255 upregulated genes and 213 downregulated genes. The results of GO and the KEGG pathway enrichment analysis indicated that these up-regulated genes were highly associated with the immune-related biological processes, and the down-regulated genes are involved in biological processes related to organonitrogen compound, multicellular organismal process, ion transport. Finally, a total of 23 hub genes were identified based on PPI and the subcluster analysis through MCODE software plugin in Cytoscape, which included 19 upregulated hub genes, such as CD28, CD3D, CD8B, CD8A, CD160, CXCR6, CCR3, CCR8, CCR9, TLR3, EOMES, GZMB, PTGDR2, CXCL8, GZMA, FASLG, GPR18, PRF1, IDO1, and additional 4 downregulated hub genes, such as CNR1, GPER1, TMIGD3, GRM2. KEGG pathway enrichment analysis and GO functional annotation showed that differentially expressed genes were primarily associated with the items related to cytokine-cytokine receptor interaction, natural killer cell mediated cytotoxicity, hematopoietic cell lineage, T cell receptor signaling pathway, phospholipase D signaling pathway, cell adhesion molecules, viral protein interaction with cytokine and cytokine receptor, primary immunodeficiency, graft-versus-host disease, type 1 diabetes mellitus. Conclusions Some lymphocytes such as T cells and natural killer cells, cytokines and chemokines participate in the immune process, which plays an important role in the early treatment of septic shock, and CD160, CNR1, GPER1, and GRM2 may be considered as new biomarkers.
This paper aims to analyze the impact of splenic vein thrombosis (SVT) on the hemodynamic parameters in hepatic portal vein system. Based on computed tomography (CT) images of a patient with portal hypertension and commercial software MIMICS, the patient's portal venous system model was reconstructed. Color Doppler ultrasound method was used to measure the blood flow velocity in portal vein system and then the blood flow velocities were used as the inlet boundary conditions of simulation. By using the computational fluid dynamics (CFD) method, we simulated the changes of hemodynamic parameters in portal venous system with and without splenic vein thrombosis and analyzed the influence of physiological processes. The simulation results reproduced the blood flow process in portal venous system and the results showed that the splenic vein thrombosis caused serious impacts on hemodynamics. When blood flowed through the thrombosis, blood pressure reduced, flow velocity and wall shear stress increased. Flow resistance increased, blood flow velocity slowed down, the pressure gradient and wall shear stress distribution were more uniform in portal vein. The blood supply to liver decreased. Splenic vein thrombosis led to the possibility of forming new thrombosis in portal vein and surroundings.
ObjectiveTo explore the hemodynamic effects of inhaled nitric oxide (iNO) on postoperative hemodynamic in patients with cyanotic congenital heart disease (CHD) combined with decreased pulmonary blood flow.MethodsFrom 2014 to 2018, there were 1 764 patients who received corrective repair of cyanotic CHD with decreased pulmonary blood flow in the Department of Pediatric Cardiac Surgery of Fuwai Hospital. We included 61 patients with the ratio of right ventricular systolic pressure to systolic blood pressure (SBP) ≥75% after weaning from cardiopulmonary bypass. There were 41 males and 20 females, with the age of 20.5 (9.0, 39.0) months and weight of 12.5±7.8 kg. The patients were divided into two groups: a conventional group (33 patients, conventional therapy only) and a combined therapy group (28 patients, iNO combined with conventional therapy). The hemodynamics during the first 24 hours after iNO therapy and the in-hospital outcomes of the two groups were investigated and compared.ResultsThere was no statistical difference between the two groups in demographic characteristics and surgical parameters (P>0.05). The hemodynamic effects of iNO within 24 hours included the decrease in the vasoactive inotropic score (VIS, 21.6±6.6 vs. 17.3±7.2, P=0.020) along with the increase in blood pressure (SBP: 73.7±9.7 mm Hg vs. 90.8±9.1 mm Hg, P<0.001) , the decrease in central venous pressure (10.0±3.1 mm Hg vs. 7.9±2.1 mm Hg, P=0.020), the decrease in lactate (2.2±1.7 mmol/L vs. 1.2±0.5 mmol/L, P<0.001) and increase in urine output [2.8±1.7 mL/(kg·h) vs. 4.9±2.2 mL/(kg·h), P<0.001]. The decrease of VIS at 24 h after the surgery in the conventional therapy group was not statistically significant (22.1±7.9 vs. 20.0±8.5, P=0.232). Besides, we discovered that the need for renal replacement therapy (RRT) was less in the combined therapy group than that in the conventional therapy group, especially in the moderate complicated surgery [risk adjustment in congenital heart surgery (RACHS-1) ≤3] subgroup (9.5% vs. 40.7%, P=0.016).ConclusionIn pediatric patients after corrective repair of cyanotic and pulmonary blood follow decreased CHD with increased pulmonary vascular resistance, iNO combined with conventional therapy can improve the hemodynamics effectively. Compared with the conventional therapy, the combined therapy with iNO can decrease the VIS and the need for RRT, which is beneficial to the postoperative recovery of patients.
Heart failure is one kind of cardiovascular disease with high risk and high incidence. As an effective treatment of heart failure, artificial heart is gradually used in clinical treatment. Blood compatibility is an important parameter or index of artificial heart, and how to evaluate it through hemodynamic design and in vitro hemolysis test is a research hotspot in the industry. This paper first reviews the research progress in hemodynamic optimization and in vitro hemolysis evaluation of artificial heart, and then introduces the research achievements and progress of the team in related fields. The hemodynamic performance of the blood pump optimized in this paper can meet the needs of use. The normalized index of hemolysis obtained by in standard vitro hemolysis test is less than 0.1 g/100 L, which has good hemolysis performance in vitro. The optimization method described in this paper is suitable for most of the development of blood pump and can provide reference for related research work.