Arterial Tree Research Articles

Coronary Arteries and Their Variations: A Retrospective Study at a Tertiary Care Centre in Tamil Nadu, India

Introduction: Anatomic variations in coronary circulation are commonly identified during dissection and angiographic procedures. The right and left coronary arteries, which supply blood to the heart, originate from the corresponding aortic sinuses. Occlusion of the coronary artery can lead to heart ischaemia, resulting in myocardial infarction and death. Understanding such variations is crucial for cardiac catheterisation, coronary artery bypass surgery, and the identification of fistulous communication, dissection, and rupture of the coronary artery. Aim: To identify the branching pattern of coronary arteries, their origin, dominance in the heart, and variations in angiographic images. Materials and Methods: The present retrospective cross-sectional study analysed 100 angiographic pictures collected from the Cardiology Department at PSG Institute of Medical Sciences and Research, Coimbatore, Tamil Nadu, India, between November 2017 and April 2018. The data were analysed from March 2022 to June 2022 to determine the origin, branching pattern, and variations of the coronary arteries. The coronary arteries and their branches were carefully traced and followed to their termination, and normal and variant anatomy were analysed. Descriptive statistics were used, and the results were expressed in frequency and percentage. Results: A total of 100 patients presented with chest pain/dyspnoea and underwent diagnostic coronary artery catheterisation in the PSG Cardiology Department. Among them, 75% were males and 25% were females, with ages ranging from 14 to 82 years (mean age of 48 years). The dominant form of coronary circulation was found to be right dominance (42%), followed by co-dominance (30%). In one study, a higher origin of the right coronary artery from the ascending aorta was observed. An anomalous vessel arising from the right coronary artery was identified in an angiogram. Separate origins of the circumflex artery and left anterior descending artery from the left coronary artery were observed in another angiogram. Fistulous communications were found in two angiograms: one between the pulmonary artery and the diagonal branch of the left anterior descending artery, and the other between the right coronary artery and the septal branch of the left anterior descending artery. Additionally, two other studies identified dissection and spontaneous rupture of the coronary artery. Conclusion: Identifying anomalous vessels and recognising other variations are crucial for appropriate intervention, treatment, and improved outcomes. Angiography can help identify and treat variations in the course and branching pattern of the coronary artery as early as possible to avoid complications.

Dynamic Estimation of Cardiovascular State From Arterial Blood Pressure Recordings.

Real-time estimation of patient cardiovascular states, including cardiac output and systemic vascular resistance, is necessary for personalized hemodynamic monitoring and management. Highly invasive measurements enable reliable estimation of these states but increase patient risk. Prior methods using minimally invasive measurements reduce patient risk but have produced unreliable estimates limited due to trade-offs in accuracy and time resolution. Our objective was to develop an approach to estimate cardiac output and systemic vascular resistance with both a high time resolution and high accuracy from minimally invasive measurements. Using the two-element Windkessel model, we formulated a state-space method to estimate a dynamic time constant - the product of systemic vascular resistance and compliance - from arterial blood pressure measurements. From this time constant, we derived proportional estimates of systemic vascular resistance and cardiac output. We then validated our method with a swine cardiovascular dataset. Our estimates produced using arterial blood pressure measurements not only closely align with those using highly invasive measurements, but also closely align when derived from three separate locations on the arterial tree. Moreover, our estimates predictably change in response to standard cardiovascular drugs. Overall, our approach produces reliable, real-time estimates of cardiovascular states crucial for monitoring and control of the cardiovascular system.

Morphology of the aortic arch branching pattern in raccoon dogs (Nyctereutes procyonoides, Gray, 1834).

Aortic arch (AA) branching patterns vary among different mammalian species. Most previous studies have focused on dogs, whereas those on raccoon dogs remain unexplored. The objective of this study was to describe the AA branching pattern in raccoon dogs and compare their morphological features with those of other carnivores. We prepared silicone cast specimens from a total of 36 raccoon dog carcasses via retrograde injection through the abdominal aorta. The brachiocephalic trunk (BCT) branching patterns were classified based on the relationship between the left and right common carotid arteries. The subclavian artery (SB) branching pattern was examined based on the order of the four major branches: the vertebral artery (VT), costocervical trunk (CCT), superficial cervical artery (SC), and internal thoracic artery (IT). In most cases (88.6%), the BCT branched off from the left common carotid artery and terminated in the right common carotid and right subclavian arteries. In the remaining cases (11.4%), the BCT formed a bicarotid trunk. The SB exhibited various branching patterns, with 26 observed types. Based on the branching order of the four major branches, we identified the main branching pattern, in which the VT branched first (98.6%), the CCT branched second (81.9%), the SC branched third (62.5%), and the IT branched fourth (52.8%). The AA branching pattern in raccoon dogs exhibited various branching patterns with both similarities and differences compared to other carnivores.

Comprehensive analysis of the rostral and caudal cerebral artery branching patterns in the dromedary camel (Camelus dromedarius).

In mammals, the cerebral cortex depends on a robust blood supply for optimal function. The rostral and caudal cerebral arteries are critical for supplying the cerebrum. This study presents the first detailed anatomical description of the rostral and caudal cerebral arteries of dromedary camels (Camelus dromedarius), including their origins, routes, and complex branching patterns. A sample of 55 heads from male dromedary camels aged 2-6 years was analyzed using advanced casting techniques with various casting materials to provide precise visualization of these arterial structures. The rostral cerebral arteries originate dorsally from the rostral epidural rete mirabile (RERM), while the caudal cerebral arteries arise from the caudal communicating artery, which is another branch of the RERM. Both sets of arteries give rise to multiple cortical branches responsible for supplying the medial aspects of the frontal, parietal, and temporal lobes, as well as the medial and caudal regions of the occipital lobes. This study significantly expands our understanding of the cerebrovascular anatomy of dromedary camels. Our findings have potential implications for veterinary medicine in the diagnosis and treatment of neurological disorders in camels and may offer insights into broader comparative neuroscience research.

Clinical Presentation and Therapy of Tetralogy of Fallot and Double-Outlet Right Ventricle.

Tetralogy of Fallot (TOF) is the most common cyanotic heart defect. TOF consists of the combination of four anomalies (Fig. 35.1): (1) a large malalignment ventricular septal defect, (2) an obstruction of the right ventricular outflow tract (usually infundibular and valvular pulmonary stenosis with a small pulmonary valve annulus and supravalvular stenosis, (3) an aorta that "overrides" the ventricular septal defect, and (4) right ventricular hypertrophy. TOF represents 4-8% of congenital heart defects. Specific variations of TOF include all forms of pulmonary atresia with VSD and absent pulmonary valve syndrome. In addition, the left and right main pulmonary arteries may be stenotic or hypoplastic. In these cases, there may be major aortopulmonary collateral arteries (MAPCAs) which are vessels arising from the aorta or the subclavian arteries that supply segments of the pulmonary arterial tree. Additional variations include an ASD (Pentalogy of Fallot), a right aortic arch, and coronary abnormalities.

Debris generated by laser and/or balloon cause cerebral infarction with different severity.

The purpose of this study is to determine the effects that debris generated by laser and/or balloon on the brain. Debris generated by laser, balloon, and laser combined with balloon were collected and then injected into rats' left common carotid artery. Rats were divided into five groups: sham, saline, laser (L), balloon (B), and laser combined with balloon (LB). The cognition ability of rats was evaluated by Morris water maze. Cerebral blood flow (CBF) was examined by laser speckle. TTC staining and MRI scan were conducted to detect cerebral ischemic infarction. Intracranial arteries in rats were visualized by MRI angiography via contrast medium injected via tail vein. Immunohistologic staining for NeuN and Iba1 and hematoxylin-eosin staining were performed to assess brain infarction. White matter demyelination was assessed by Luxol fast blue staining. Long-term memory and CBF of rats in different groups exhibited no significant difference. No obstruction sign in intracranial artery tree was noticed in each group. Debris generated by different treatments all caused brain infarction. Infarction lesion caused by debris produced by balloon was much more severe than the one caused by debris generated by laser. While the LB group lay in between. The thickness of white matter decreased in the B group, but not in the L and LB groups. Rat brain has a tolerance for debris as cognition ability and cerebral blood flow are not significantly declined. The severity of cerebral infarction varies by debris generated by different treatments.

Analytic solution for pulse wave propagation in flexible tubes with application to a patient-specific arterial tree

In this paper, we present an analytic solution for pulse wave propagation in a flexible arterial model with tapering, physiological boundary conditions and variable wall properties (wall elasticity and thickness). The change of wall properties follows a profile that is proportional to $r^\alpha$ , where $r$ represents the lumen radius and $\alpha$ is a material coefficient. The cross-sectionally averaged velocity and pressure are obtained by solving a hyperbolic system derived from the mass and momentum conservations, and they are expressed in Bessel functions of order $(4-\alpha )/(3-\alpha )$ and $1/(3-\alpha )$ , respectively. The solution is successfully validated by comparing it with numerical results from three-dimensional (3-D) fluid–structure interaction simulations. Subsequently, the solution is employed to study pulse wave propagation in an arterial model, revealing that the wall properties and the physiological outlet boundary conditions, such as the resistor–capacitor–resistor (RCR) model, play a crucial role in characterizing the input impedance and reflection coefficient. At low-frequency range, the input impedance is found to be insensitive to the wall properties and is primarily determined by the RCR parameters. At high-frequency range, the input impedance oscillates around the local characteristic impedance, and the oscillation amplitude varies non-monotonically with $\alpha$ . Expressions for the input impedance at both low-frequency and high-frequency limits are presented. This analytic solution is also successfully applied to model flow inside a patient-specific arterial tree, with the maximum relative errors in pressure and flow rate never exceeding $1.6\,\%$ and $9.0\,\%$ when compared with results from 3-D numerical simulations.

HEG1 Protects Against Atherosclerosis by Regulating Stable Flow-Induced KLF2/4 Expression in Endothelial Cells.

Atherosclerosis preferentially occurs in arterial regions of disturbed blood flow, and stable flow (s-flow) protects against atherosclerosis by incompletely understood mechanisms. Our single-cell RNA-sequencing data using the mouse partial carotid ligation model was reanalyzed, which identified Heart-of-glass 1 (HEG1) as an s-flow-induced gene. HEG1 expression was studied by immunostaining, quantitive polymerase chain reaction, hybridization chain reaction, and Western blot in mouse arteries, human aortic endothelial cells (HAECs), and human coronary arteries. A small interfering RNA-mediated knockdown of HEG1 was used to study its function and signaling mechanisms in HAECs under various flow conditions using a cone-and-plate shear device. We generated endothelial-targeted, tamoxifen-inducible HEG1 knockout (HEG1iECKO) mice. To determine the role of HEG1 in atherosclerosis, HEG1iECKO and littermate-control mice were injected with an adeno-associated virus-PCSK9 [proprotein convertase subtilisin/kexin type 9] and fed a Western diet to induce hypercholesterolemia either for 2 weeks with partial carotid ligation or 2 months without the surgery. S-flow induced HEG1 expression at the mRNA and protein levels in vivo and in vitro. S-flow stimulated HEG1 protein translocation to the downstream side of HAECs and release into the media, followed by increased messenger RNA and protein expression. HEG1 knockdown prevented s-flow-induced endothelial responses, including monocyte adhesion, permeability, and migration. Mechanistically, HEG1 knockdown prevented s-flow-induced KLF2/4 (Kruppel-like factor 2/4) expression by regulating its intracellular binding partner KRIT1 (Krev interaction trapped protein 1) and the MEKK3-MEK5-ERK5-MEF2 pathway in HAECs. Compared with littermate controls, HEG1iECKO mice exposed to hypercholesterolemia for 2 weeks and partial carotid ligation developed advanced atherosclerotic plaques, featuring increased necrotic core area, thin-capped fibroatheroma, inflammation, and intraplaque hemorrhage. In a conventional Western diet model for 2 months, HEG1iECKO mice also showed an exacerbated atherosclerosis development in the arterial tree in both sexes and the aortic sinus in males but not in females. Moreover, endothelial HEG1 expression was reduced in human coronary arteries with advanced atherosclerotic plaques. Our findings indicate that HEG1 is a novel mediator of atheroprotective endothelial responses to flow and a potential therapeutic target.

Isolated coronary artery ectasia presenting as inferior-posterior STEMI—a case-based state-of-the-art review of the current literature

Abstract Background This review is based on the case of a 71-year-old female patient, with cardiovascular risk factors, who was referred for emergency cardiological evaluation after experiencing severe anterior chest pain that had lasted for more than 5 hours at the time of admission. A diagnosis of inferior-posterior ST-segment elevation myocardial infarction was established, and emergency coronary angiography was performed. It revealed severe, diffuse dilation of the entire arterial coronary tree with slow flow and the presence of a large quantity of thrombotic material in the right coronary artery. Thromboaspiration was deemed unfit since the operator believed that there was a high risk of distal embolization with subsequent no-reflow, when passing with the catheter. As such, the patient started receiving anticoagulant therapy, and after one month she was scheduled for a control angiogram. The follow-up coronary angiography identified complete dissolution of the thrombus from the right coronary artery and a moderate stenosis in the distal segment, so no stent implantation was required. Rationale for review After performing a complete and comprehensive differential diagnosis, presence of isolated coronary artery ectasia was established. Coronary artery ectasia is a rare disease, usually found incidentally during coronary angiograms performed for other indications (chronic and acute coronary syndromes) with a vast etiology and complex pathophysiology. Because there are common morphopathologic pathways between coronary artery ectasia and atherosclerotic coronary artery disease, the clinical presentation of the former might have similar characteristics with the latter, but the management and prognosis of these patients is much less studied compared to the patients suffering from different phenotypes of coronary atherosclerosis. This review aims to summarize the etiopathogenesis, clinical presentation, diagnostic modalities, and different management pathways of coronary artery ectasia.

The Process of Plaque Rupture: The Role of Vasa Vasorum and Medial Smooth Muscle Contraction Monitored by the Cardio-Ankle Vascular Index

A warning sign for impending cardiovascular events is not fully established. In the process of plaque rupture, the formation of vulnerable plaque is important, and oxidized cholesterols play an important role in its progression. Furthermore, the significance of vasa vasorum penetrating the medial smooth muscle layer and being rich in atheromatous lesions should be noted. The cardio-ankle vascular index (CAVI) is a new arterial stiffness index of the arterial tree from the origin of the aorta to the ankle. The CAVI reflects functional stiffness, in addition to structural stiffness. The rapid rise in the CAVI means medial smooth muscle cell contraction and strangling vasa vasorum. A rapid rise in the CAVI in people after a big earthquake, following a high frequency of cardiovascular events has been reported. There are several cases that showed a rapid rise in the CAVI a few weeks or months before suffering cardiovascular events. To explain these sequences of events, we proposed a hypothesis: a rapid rise in the CAVI means medial smooth muscle contraction, strangling vasa vasorum, leading to ischemia and the necrosis of vulnerable plaque, and then the plaque ruptures. In individuals having a high CAVI, further rapid rise in the CAVI might be a warning sign for impending cardiovascular events. In such cases, treatments to decrease the CAVI better be taken soon.

Developing and Validating a Simple Risk Score for Patients with Acute Myocardial Infarction.

Mortality from acute myocardial infarction (AMI) remains substantial. The current study is aimed at developing a novel simple risk score for AMI. The Coronary Artery Tree description and Lesion EvaluaTion (CatLet) extended validation trial (ChiCTR2000033730) and the CatLet validation trial (ChiCTR-POC-17013536), both being registered with <ext-link ext-link-type="uri" xlink:href="http://chictr.org" xmlns:xlink="http://www.w3.org/1999/xlink">chictr.org</ext-link>, served as the derivation and validation datasets, respectively. Both datasets included 1,018 and 308 patients, respectively. They all suffered from AMI and underwent percutaneous intervention (PCI). The endpoint was 4-year all-cause death. Lasso regression analysis was used for covariate selection and coefficient estimation. Of 26 candidate predictor variables, the four strongest predictors for 4-year mortality were included in this novel risk score with an acronym of BACEF (serum alBumin, Age, serum Creatinine, and LVEF). This score was well calibrated and yielded an AUC (95% CI) statistics of 0.84 (0.80-0.87) in internal validation, 0.89 (0.83-0.95) in internal-external (temporal) validation, and 0.83 (0.77-0.89) in external validation. Notably, it outperformed the ACEF, ACEF II, GRACE scores with respect to 4-year mortality prediction. A simple risk score for 4-year mortality risk stratification was developed, extensively validated, and calibrated in patients with AMI. This novel BACEF score may be a useful risk stratification tool for patients with AMI.

Stromal netrin 1 coordinates renal arteriogenesis and mural cell differentiation.

The kidney vasculature has a complex architecture that is essential for renal function. The molecular mechanisms that direct development of kidney blood vessels are poorly characterized. We identified a regionally restricted, stroma-derived signaling molecule, netrin 1 (Ntn1), as a regulator of renal vascular patterning in mice. Stromal progenitor (SP)-specific ablation of Ntn1 (Ntn1SPKO) resulted in smaller kidneys with fewer glomeruli, as well as profound defects of the renal artery and transient blood flow disruption. Notably, Ntn1 ablation resulted in loss of arterial vascular smooth muscle cell (vSMC) coverage and in ectopic SMC deposition at the kidney surface. This was accompanied by dramatic reduction of arterial tree branching that perdured postnatally. Transcriptomic analysis of Ntn1SPKO kidneys revealed dysregulation of vSMC differentiation, including downregulation of Klf4, which we find expressed in a subset of SPs. Stromal Klf4 deletion similarly resulted in decreased smooth muscle coverage and arterial branching without, however, the disruption of renal artery patterning and perfusion seen in Ntn1SPKO. These data suggest a stromal Ntn1-Klf4 axis that regulates stromal differentiation and reinforces stromal-derived smooth muscle as a key regulator of renal blood vessel formation.

Comprehensive anatomical study of meningeal arteries in dromedaries

This study provides a detailed, in-depth analysis of the anatomy, topography, and branching patterns of the meningeal arteries in dromedary camels, a subject that has not previously been thoroughly studied in animals, providing insight into the intricate biological adaptations that allow them to survive in harsh environments. By precisely examining 20 heads obtained from freshly slaughtered dromedaries, we revealed the origins and topologies of the rostral, middle, and caudal meningeal arteries using advanced casting techniques for precise rendering. Our findings indicate that the rostral meningeal artery derives from the external ethmoidal artery and primarily supplies the rostrodorsal region of the frontal lobe. The middle meningeal artery provides blood to approximately two-thirds of the brain meninges. The caudal meningeal artery is derived from the occipital artery and supplies the meninges covering the cerebellum, caudal part of the falx cerebri, and tentorium cerebelli. Significantly, our study revealed the presence of accessory branches originating from the rostral epidural rete mirabile, a finding not previously described in the existing literature. These branches supply the meninges of the frontal and lateral regions of the frontal lobes. This novel study advances our understanding of the meningeal arteries in dromedaries and has significant implications for advancements in veterinary neuroscience.

Central systolic blood pressure as a risk for the accelerated progression of arterial stiffness

Abstract In the arterial tree, the systolic blood pressure (SBP) exhibits a pressure gradient from central to peripheral and is higher in the periphery because of pressure wave reflection. However, this gradient is attenuated with the elevation of central SBP (cSBP) in case with abnormal pressure wave reflection in arterial tree. It remains unclear whether increase of the cSBP might be an independent risk for the accelerated progression of arterial stiffness. Using the latent growth curve model (LGCM) analysis, this prospective observational study was conducted to examine whether elevation of the cSBP might be an independent risk for the accelerated progression of arterial stiffness in middle-aged Japanese men.In this 9-year prospective observational study, 3862 middle-aged Japanese men (42 ± 9 years old) without cerebrocardiovascular disease at the study baseline underwent annual measurements of the brachial-ankle pulse wave velocity (baPWV), and cSBP, estimated by radial pressure wave analysis as the second peak of radial pressure wave form (SBP2). During the follow-up period (6.4 ± 2.5), significant increases of baPWV and SBP2 were observed in all subjects. Analysis using the LGCM confirmed that the SBP2, a maker of cSBP (B=0.260, P &amp;lt; 0.001) was significant determinants of the slope of annual changes of baPWV during the study period. Our finding suggests that elevated cSBP is an independent risk for the accelerated progression of arterial stiffness in middle-aged Japanese men.

Abstract 17842: 3D Visualization and Quantitative Assessment of the Pulmonary Arteries on CT Using Deep Learning Segmentation

Introduction: Assessment of the pulmonary arteries (PA) on CT scan is typically qualitative and requires review of hundreds of images. PA segmentation would enable creation of 3D reconstructions that visualize the entire pulmonary arterial tree in a single image, similar to catheter angiography, and also enable quantification of pathophysiologic changes. Manual segmentation is very time-consuming, but deep-learning (DL) can automate the process. Hypothesis: A DL segmentation algorithm can be used to automatically generate 3D reconstructions of the PAs and quantify morphologic changes seen in Chronic Thromboembolic Pulmonary Hypertension (CTEPH) and Pulmonary Arterial Hypertension (PAH). Methods: A DL algorithm based on a 3D U-Net architecture which segments PAs larger than 2 mm was trained and validated on a total of 250 contrast-enhanced CT chest. The study group included 15 CTEPH and 15 PAH patients seen consecutively in pulmonary hypertension (PH) clinic in 2022 with prior CT chest and right heart catheterization, and 10 additional patients with prior CT chest and no evidence of PH on same day echo (normal). After running the DL algorithm on CTs, 3D renderings were created from segmentations and the relative volume of the central, interlobar, and segmental/subsegmental PAs was derived. Results: 3D renderings of PAH and CTEPH patients showed larger central and interlobar PAs compared with those of normal patients, whereas segmental and subsegmental PAs were smaller and pruned in CTEPH patients (Figure). Quantitatively, the volume of the central and interlobar PAs was higher in CTEPH and PAH compared to normal (p &lt; 0.05). The combined volume of segmental/subsegmental PAs was smaller in CTEPH patients relative to normal and PAH patients (p &lt; 0.005). Conclusions: DL segmentation enables intuitive visualization and quantification of the morphologic changes to the PAs seen in conditions causing PH. This method may improve diagnosis and assessment of PH on CT.

Cardio-Ankle Vascular Index and Aging: Differences between CAVI and CAVI0.

Cardio-ankle vascular index (CAVI) and CAVI0 (a mathematical expression derived from CAVI, supposed to be less dependent on blood pressure), can describe arterial stiffness, considering a wide proportion of the arterial tree. The aim of this study was to examine the relationship between CAVI, CAVI0 and aging, looking at the differences between the two arterial stiffness indexes. A total of 191 patients (68 male, mean age 68.3 ± 14.4 years) referred to the Geriatric Ward and Outpatient Clinic at Verona University Hospital were included and underwent a comprehensive clinical evaluation. CAVI and CAVI0 were obtained for each. CAVI0 steeply rises in the elderly age strata, widening the gap between CAVI and CAVI0. An inverse relationship is evident between CAVI0 and DBP in older patients, and CAVI0 is shown to be dependent on age, DBP and age-DBP interaction (R2 = 0.508). Age modifies the effect of DBP on CAVI0, but not on CAVI. The real new findings of our study are that the association between CAVI0 and diastolic blood pressure (DBP) is modified by age, whereas the association between CAVI and DBP is not modified by age. From a clinical point of view, these are very important findings, as DBP decreases with aging, affecting in elderly populations the reliability of CAVI0, which strictly depends on DBP in the formula to calculate it. To monitor the effect of CV therapies, progression of CV diseases and to evaluate clinical outcomes in elderly populations, we suggest using CAVI and not CAVI0.

A multi-stage neural network approach for coronary 3D reconstruction from uncalibrated X-ray angiography images

We present a multi-stage neural network approach for 3D reconstruction of coronary artery trees from uncalibrated 2D X-ray angiography images. This method uses several binarized images from different angles to reconstruct a 3D coronary tree without any knowledge of image acquisition parameters. The method consists of a single backbone network and separate stages for vessel centerline and radius reconstruction. The output is an analytical matrix representation of the coronary tree suitable for downstream applications such as hemodynamic modeling of local vessel narrowing (i.e., stenosis). The network was trained using a dataset of synthetic coronary trees from a vessel generator informed by both clinical image data and literature values on coronary anatomy. Our multi-stage network achieved sub-pixel accuracy in reconstructing vessel radius (RMSE = 0.16 ± 0.07 mm) and stenosis radius (MAE = 0.27 ± 0.18 mm), the most important feature used to inform diagnostic decisions. The network also led to 52% and 38% reduction in vessel centerline reconstruction errors compared to a single-stage network and projective geometry-based methods, respectively. Our method demonstrated robustness to overcome challenges such as vessel foreshortening or overlap in the input images. This work is an important step towards automated analysis of anatomic and functional disease severity in the coronary arteries.

AVDNet: Joint coronary artery and vein segmentation with topological consistency

Coronary CT angiography (CCTA) is an effective and non-invasive method for coronary artery disease diagnosis. Extracting an accurate coronary artery tree from CCTA image is essential for centerline extraction, plaque detection, and stenosis quantification. In practice, data quality varies. Sometimes, the arteries and veins have similar intensities and locate closely, which may confuse segmentation algorithms, even deep learning based ones, to obtain accurate arteries. However, it is not always feasible to re-scan the patient for better image quality. In this paper, we propose an artery and vein disentanglement network (AVDNet) for robust and accurate segmentation by incorporating the coronary vein into the segmentation task. This is the first work to segment coronary artery and vein at the same time. The AVDNet consists of an image based vessel recognition network (IVRN) and a topology based vessel refinement network (TVRN). IVRN learns to segment the arteries and veins, while TVRN learns to correct the segmentation errors based on topology consistency. We also design a novel inverse distance weighted dice (IDD) loss function to recover more thin vessel branches and preserve the vascular boundaries. Extensive experiments are conducted on a multi-center dataset of 700 patients. Quantitative and qualitative results demonstrate the effectiveness of the proposed method by comparing it with state-of-the-art methods and different variants. Prediction results of the AVDNet on the Automated Segmentation of Coronary Artery Challenge dataset are avaliabel at https://github.com/WennyJJ/Coronary-Artery-Vein-Segmentation for follow-up research.

Association of serum cystatin C level with coronary atherosclerotic plaque burden: a comprehensive analysis of observational studies and genetic study

Background and AimsEpidemiological studies show that high circulating cystatin C is associated with risk of cardiovascular disease (CVD), independent of creatinine-based renal function measurements. However, the relationship between serum cystatin C level and coronary atherosclerotic plaque burden is limited. We aimed to evaluate the relationship between circulating cystatin C and coronary atherosclerotic plaque burden.MethodsThis study was a cross-sectional study based on China community population. Measurements of plaque burden were based on the segment-involvement score (SIS) and segment stenosis score (SSS), which derived from the Coronary Artery Tree Model Depicting Coronary Artery Plaque Scores. Logistic regression model was used to demonstrate the association between cystatin C level and coronary artery plaque burden. Mendelian randomization (MR) analyses were conducted to assess the causal effect of cystatin C level on coronary atherosclerosis risk.ResultsA total of 3,043 objects were included in the present study. The odds risks (OR) of severe plaque burden in the highest serum cystatin C levels (OR: 2.50; Cl:1.59–3.91; P < 0.001) and medium-level cystatin C levels (OR: 1.86; 95% Cl: 1.21–2.88; P = 0.005) were significantly higher after fulled adjusted confounders compared with the lowest levels of serum cystatin C by SSS. The MR analysis showed that genetic predicted cystatin C levels was associated with an increased risk of coronary atherosclerosis (OR, 1.004; 95% CI, 1.002–1.006, P < 0.001) .ConclusionElevated serum cystatin C levels were associated with coronary atherosclerotic plaque burden. Cystatin C levels had a causal effect on an increased risk of coronary atherosclerosis at the genetic level.What is already known on this topic?Coronary artery disease is currently the most common cardiovascular disease and the leading global cause of mortality. Previous studies reported that higher serum cystatin C levels were associated with an increased risk for future cardiovascular events, independent of the normal creatinine levels or estimated glomerular filtration rate (eGFR) values. The presence of high-risk coronary atherosclerotic plaque burden is associated with increased risk of cardiovascular events. However, the association between serum cystatin C and coronary atherosclerotic plaque burden is not very clear.What this study adds?Our study demonstrated that the elevated serum cystatin C levels were associated with coronary atherosclerotic plaque burden. In addition, we found that serum cystatin C levels had a causal effect on an increased risk of coronary atherosclerosis at the genetic level.How this study might affect research, practice or policy?Current research finds that serum cystatin C levels were associated with coronary atherosclerosis. The metabolic pathway of cystatin C could be a target for new therapies against CAD.

Left Ventricular Ejection Time Estimation from Blood Pressure and Photoplethysmography Signals Based on Tidal Wave

Left ventricular ejection time (LVET) is an important parameter for assessing cardiovascular disorders. In a medical office, it is typically measured using the Tissue Doppler Imaging technique, but new wearable devices have led to a growing interest in integrating this parameter into them, increasing accessibility to personalized healthcare for users and patients. In the cardiovascular domain, photoplethysmography (PPG) is a promising technology that shares two distinctive features with invasive arterial blood pressure (ABP) tracing: the tidal wave (TDW) and the dicrotic wave (DCW). In the early years of cardiovascular research, the duration of the dicrotic point was initially linked to the ending phase of left ventricular ejection. Subsequent studies reported deviations from the initial association, suggesting that the ejection period is related to the tidal wave feature. In this current study, we measured left ventricular ejection time in both ABP and PPG waveforms, considering recent research results. A total of 27,000 cardiac cycles were analyzed for both afore-mentioned signals. The reference value for ejection time was computed based on the T-wave segment duration from the electrocardiogram waveform. In lower blood pressure, which is associated with decreased heart contractility, the results indicated an underestimation of −29 ± 19 ms in ABP and an overestimation of 18 ± 31 ms in PPG. On the other side of the spectrum, during increased contractility, the minimum errors were −3 ± 18 ms and 4 ± 33 ms, respectively. Since the tidal wave feature is strongly affected by arterial tree compliance, the population evaluation results indicate a Pearson’s correlation factor of 0.58 in the ABP case, and 0.53 in PPG. These findings highlight the need for advanced compensation techniques, in particular for PPG assessment, to achieve clinical-grade accuracy.