CASE REPORT | doi:10.20944/preprints202102.0167.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: single coronary artery; aortic valve surgery, coronary artery bypass grafting surgery; case report
Online: 8 February 2021 (15:42:53 CET)
A single coronary artery is a very rare condition, commonly associated with other congenital anomalies. It could be generally classified as neither benign nor malignant form of congenital coronary artery anomalies since its pathophysiological and clinical implications grossly depend on different anatomical patterns defined by the site of origin and distribution of the branches. By presenting the patient with an isolated single coronary artery, who underwent successful combined aortic valve replacement and coronary artery bypass grafting surgery, we intend to distinguish casual from causal in this extremely rare clinical and surgical scenario. This is the first-ever case published, combining such underlying pathology, clinical presentation, and surgical treatment.
ARTICLE | doi:10.20944/preprints201808.0033.v1
Online: 2 August 2018 (05:20:58 CEST)
Sonic Hedgehog (Shh) is a prototypical angiogenic agent with a crucial role in the regulation of angiogenesis. Experimental studies have shown that Shh is upregulated in response to ischemia. Also, Shh may be found on the surface of circulating microparticles (MPs) and MPs bearing Shh (Shh+ MPs) have shown the ability to contribute to reparative neovascularization after ischemic injury in mice. In this study, the plasma number of Shh+ MPs in patients with peripheral artery disease (PAD) and control subjects without PAD. We found significantly higher number of Shh+ MPs in plasma of subjects with PAD, compared to controls, while the global number of MPs – produced either by endothelial cells, platelets, leukocytes, and erythrocytes – was not different between PAD patients and controls. Interestingly, the concentration of Shh protein unbound to MPs – which was measured in MP-depleted plasma – was not different between subjects with PAD and controls, indicating that, in the setting of PAD, the call for Shh recapitulation does not lead to secretion of protein into the blood but to binding of the protein to the membrane of MPs. These findings provide novel insights on the mechanisms through which the Shh signaling is reactivated during ischemia in humans, with potentially important fundamental and clinical implications.
ARTICLE | doi:10.20944/preprints202001.0220.v1
Subject: Mathematics & Computer Science, Artificial Intelligence & Robotics Keywords: heart disease; coronary artery disease; machine learning; deep learning; predictive features; coronary artery disease diagnosis; health informatics
Online: 20 January 2020 (09:11:14 CET)
Heart disease is one of the most common diseases in middle-aged citizens. Among the vast number of heart diseases, coronary artery disease (CAD) is considered a common cardiovascular disease with a high death rate. The most popular tool for diagnosing CAD is the use of medical imaging, e.g., angiography. However, angiography is known for being costly and also associated with a number of side effects. Hence, the purpose of this study is to increase the accuracy of coronary heart disease diagnosis by selecting significant predictive features in order of their ranking. In this study, we propose an integrated method using machine learning. The machine learning methods of random trees (RTs), the decision tree of C5.0, support vector machine (SVM), the decision tree of Chi-squared automatic interaction detection (CHAID) are used in this study. The proposed method shows promising results and the study confirms that the RTs model outperforms other models.
REVIEW | doi:10.20944/preprints202104.0114.v2
Subject: Medicine & Pharmacology, Allergology Keywords: Anxiety, complementary therapies, coronary artery disease, pain
Online: 15 April 2021 (12:56:29 CEST)
Cardiovascular disease is the first leading cause of death in the world. Patients with cardiovascular disease may experience various problems, including physiological and psychological problems. Apart from pharmacological therapy, complementary therapy is necessary as a support to conventional medicine. This review aims to describe complementary and alternative therapies for pain and anxiety in patients with cardiovascular disease. This review utilized data from ProQuest, ScienceDirect, and PubMed with search keywords of "Complementary" AND "Nursing" AND "Pain" AND "Anxiety" AND "Coronary artery disease". Ten articles that met the inclusion criteria were analyzed. The results show that nursing actions increasingly develop along with the patient needs. One form of holistic nursing action is complementary and alternative therapy (CAT) that consists of three categories: body-based methods, mind therapies, and sensory therapies. CAT has positive impacts on patients with heart disease. It can reduce anxiety and pain, lower blood pressure, and improve the quality of life. This review also shows that CAT has a positive impact on the recovery of patients with heart disease. Proper therapeutic management should be implemented to reduce the risks of physiological and psychological problems in patients.
ARTICLE | doi:10.20944/preprints201810.0171.v3
Subject: Medicine & Pharmacology, General Medical Research Keywords: genome-wide polygenic score; coronary artery disease; AUC
Online: 6 December 2018 (07:06:32 CET)
A recent study claimed that genome-wide polygenic scores (GPSs) for five common diseases could identify individuals with risk equivalent to monogenic mutations. Receiver operator curve analyses were reported to have areas under the curve (AUCs) ranging from 0.63 for inflammatory bowel disease up to 0.81 for coronary artery disease (CAD) but these models also included age and sex, themselves strong predictors of risk. The GPS for CAD identified 8% of the population at threefold increased risk, which it was claimed was comparable to the excess risk from monogenic mutations. In the present study attempts were made to model the distribution of the GPS for CAD to match the information provided. These models were based on the reported distribution of prevalence by centile of GPS and on the distribution of GPS in controls and cases and were fitted to the reported results using linear approximations to the distributions and using simulations of a liability-threshold model. It was impossible to produce a compatible model in which the GPS produced an AUC as high as 0.81 and the most plausible estimate was that the true AUC was only 0.65. The reported distributions of the GPS in cases and controls overlap so much that they are not compatible with an AUC of 0.7 or higher. The AUC of the GPS for these diseases is modest. Furthermore, the literature robustly demonstrates that true CAD risk associated with monogenic mutations is much higher than the threefold increase which is predicted by the GPS. Together, these findings cast doubt on the clinical utility of the GPS.
CASE REPORT | doi:10.20944/preprints202104.0337.v2
Subject: Medicine & Pharmacology, Cardiology Keywords: coronary artery disease, acute coronary syndrome, inflammation, case report
Online: 13 April 2021 (13:14:55 CEST)
Background: Although persistent systemic inflammation is considered to be predictive for future cardiovascular events, it remains unclear whether or not C-reactive protein (CrP) plays an active role in coronary-plaque instability. Here, we report a case of a patient with failed and super-infected renal allograft as a source for systemic inflammation presenting with repeat acute coronary syndromes. Case presentation: A 52-years-old male type-2 diabetic with a failed kidney transplant who was hospitalized for acute urinary-tract infection. In the presence of other, classic cardiovascular risk factors, peak values of CrP coincided with episodes of unstable angina treated by percutaneous coronary interventions. Besides pyelonephritis, the histological examination of the kidney transplant revealed signs of chronic rejection and the presence of a renal cell carcinoma in situ. Once the renal allograft has been removed, systemic inflammation was attenuated, the patient was not re-hospitalized for acute-coronary syndrome within the next 12 months. Conclusion: In this case, systemic inflammation was paralleled by instability of coronary plaques as documented by repeat percutaneous coronary interventions.
ARTICLE | doi:10.20944/preprints201611.0004.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: thin film nitinol; carotid artery; micro mesh stent; micropatterning
Online: 1 November 2016 (06:54:40 CET)
Stenting is an alternative to endarterectomy for the treatment of carotid artery stenosis. However, stenting is associated with a higher risk of procedural stroke secondary to distal thromboembolism. Hybrid stents with a micromesh layer have been proposed to address this complication. We developed a micropatterned thin film nitinol (M-TFN) covered stent designed to prevent thromboembolism during carotid intervention. This innovation may obviate the need or work synergistically with embolic protection devices. The proposed double layered stent is low-profile, thromboresistant, and covered with a M-TFN that can be fabricated with fenestrations of varying geometries and sizes. The M-TFN was created in multiple geometries, dimensions, and porosities by sputter deposition. The efficiency of various M-TFN to capture embolic particles was evaluated in different atherosclerotic carotid stenotic conditions through in vitro tests. The covered stent prevented emboli dislodgement in the range of 70-96% during 30min duration tests. In vitro vascular cell growth study results showed that endothelial cell elongation, alignment and growth behaviour silhouettes significantly enhance specifically on the diamond-shape M-TFN with the dimensions of 145µm×20µm and a porosity of 32%. Future studies will require in-vivo testing. Our results demonstrate that M-TFN has a promising potential for carotid artery stenting.
ARTICLE | doi:10.20944/preprints201912.0378.v1
Subject: Medicine & Pharmacology, Anesthesiology Keywords: blood viscosity; transit-time flow measurement; coronary artery bypass surgery
Online: 29 December 2019 (10:22:23 CET)
Background: Transit-time flow measurement (TTFM) is frequently used to evaluate intraoperative quality control during coronary artery bypass grafting (CABG). Although TTFM has the ability to assess graft failure intraoperatively, the perioperative factors affecting TTFM during CABG surgery remain poorly understood. Methods: Patients who underwent CABG surgery at a single institution between July 2016 and May 2018 were prospectively evaluated. Patients’ demographic characteristics, previous medical history, Euroscore, the results of preoperative blood tests, and intraoperative data were recorded. TTFM and blood viscosity were measured hemodynamically, and mean flow (mL/min) and pulsatility index (PI) were recorded. Arterial blood gas was analyzed immediately after anastomosis of the left internal mammary artery (LIMA) to the left descending artery (LAD) and before sternal closure. Factors associated with TTFM were assessed by multiple linear regression analysis. Results: Of the 62 patients who underwent CABG surgery during the study period, 57 were evaluated, including 49 who underwent off-pump and eight who underwent on-pump surgery. Blood viscosity was not significantly associated with TTFM (p > 0.05). However, TTFM was significantly associated with body mass index (BMI), systolic blood pressure, and cardiac index (p < 0.05 each). Conclusions: Blood viscosity was not significantly associated with intraoperative graft flow. Blood flow of graft vessels, however, was significantly associated with BMI, systolic blood pressure, and cardiac index.
ARTICLE | doi:10.20944/preprints201806.0381.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: coronary tortuosity; myocardial ischemia; coronary artery disease; chronic stable angina.
Online: 25 June 2018 (11:02:03 CEST)
Background: Coronary tortuosity is a common angiographic finding. Scarce data is available on clinical profile of patients with coronary tortuosity (CT) and its relation with coronary artery disease (CAD). Method: A total 224 patients undergoing angiography for suspected CAD were included in the study. CT was defined by the presence of ≥3 consecutive bends of > 45 degree measured at end-diastole in an epicardial artery ≥2 mm in diameter. CT was present in 45(20.08%) patients in the study and another 45 patients without CT was randomly selected as control (NCT group). Clinical profile of CT and NCT group was compared. Results: Incidence of CT was significantly higher in females (p=0.000) and hypertensives (p=0.001) patients. CT was most commonly seen in Left circumflex coronary artery. Incidence of CAD was significantly lower in CT group as compare to NCT group (0.02). Risk factors for CAD was associated with reduced incidence of CT. Majority (88.46%) patient with CT without CAD presented with chronic stable angina out of which (65.21%) had an objective evidence of myocardial ischemia. Conclusion: CT is more commonly seen females and hypertensive patients. It has negative correlation with CAD. Risk factors of CAD do not predict CT. CT itself can lead to myocardial ischemia.
ARTICLE | doi:10.20944/preprints202301.0116.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: cost-effectiveness evaluation; heart failure; telemonitoring; pulmonary artery pressure; hemodynamic monitoring
Online: 6 January 2023 (04:41:21 CET)
Background: Real-time remote monitoring of pulmonary artery pressures has previously shown to reduce heart failure (HF) related hospitalisations and to improve quality of life of selected HF patients. The value of CardioMEMS in Southern Europe, where healthcare costs are significantly lower, remains uncertain. Objective: To evaluate the cost-effectiveness of the CardioMEMS HF system in the Spanish healthcare setting. Methodology: This single-centre study included 35 HF patients with a CardioMEMS device (treatment group) and compared them with similar patients receiving standard HF treatment (control group). The Propensity Score Matching method was used and the comparators were found using the variables age, sex, New York Heart Association class, left ventricular ejection fraction, and diabetes mellitus. Cost-effectiveness was measured as the incremental cost per quality-adjusted life year gained. Results: The CardioMEMS HF system outperformed usual management with a net monetary value difference of 2,731€ per patient at 1 year. The incremental cost per quality-adjusted life year gained was 15,896€. Results were consistent in the sensitivity analyses performed. Conclusion: This analysis suggests that remote monitoring of pulmonary artery pressure with CardioMEMS HF system is a cost-effective strategy in the Spanish healthcare setting.
ARTICLE | doi:10.20944/preprints202110.0076.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: coronary artery disease; gut microbiome; dysbiosis; obesity; Bacteroidetes; LPS; indoxyl sulfate
Online: 5 October 2021 (10:33:24 CEST)
Gut dysbiosis, alongside with high-fat diet and cigarette smoking, is considered one of the factors promoting coronary arterial disease (CAD) development. The present study aimed to research whether gut dysbiosis can increase bacterial metabolites concentration in the blood of CAD patients and what impact these metabolites can exert on endothelial cells. The gut microbiome of 15 CAD patients and age-matched 15 healthy controls was analyzed by metagenome sequencing. The in vitro impact of LPS and indoxyl sulfate at concentrations present in patients sera on endothelial cells was investigated. A metagenome sequencing analysis revealed gut dysbiosis in CAD patients, further confirmed by elevated levels of LPS and indoxyl sulfate in patients sera. CAD was associated with depletion of Bacteroidetes and Alistipes. LPS and indoxyl sulfate in meager concentrations demonstrated co-toxicity to endothelial cells inducing reactive oxygen species, E-selectin, and monocyte chemoattractant protein-1 (MCP-1) production and promoting thrombogenicity of endothelial cells confirmed by monocyte adherence. The co-toxicity of LPS and indoxyl sulfate was associated with harmful effects on endothelial cells, strongly suggesting that gut dysbiosis-associated increased intestinal permeability can initiate or promote endothelial inflammation and atherosclerosis progression.
ARTICLE | doi:10.20944/preprints202106.0234.v1
Online: 8 June 2021 (13:39:40 CEST)
Heart attacks and strokes are one of the leading causes of death in the world today, and heart attacks caused by clogged arteries that carry blood to the heart muscle are a significant part of these strokes. These are caused by the accumulation of fat particles in the walls of the arteries and the reduction of blood flow through it over a long process. The process of fat penetration in the underlying layers of the Artery wall has been the focus of many researchers, and various researches and Simulations have been done on it, in each of them, the effect of specific parameters has been considered. In the present study, the effect of blood flow rate on the flow pattern in a bifurcate artery with two ducts has been investigated using FLUENT software with Computation fluid dynamic Method. The effect of the angle between the two ducts of the Artery on the flow pattern has been investigated.
REVIEW | doi:10.20944/preprints202104.0761.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Peripheral Artery Disease; Exercise Intolerance; Exercise Limitations; Intermittent Claudication; Exercise Training
Online: 28 April 2021 (17:16:32 CEST)
Intermittent claudication (IC) is the most common symptom of peripheral artery disease (PAD). IC affects the quality of life and results in marked exercise intolerance and limitation to daily activities with increased risk of cardiovascular complications. Exercise training is the first line of conservative management in PAD. However, patients with IC Patient cannot tolerate exercise because of leg discomfort induced by physical effort. This review will address alternative rehabilitation strategies to reduce exercise limitations and improve exercise tolerance in patients with IC.
ARTICLE | doi:10.20944/preprints202002.0323.v1
Subject: Biology, Physiology Keywords: vascular; omega-3; exercise; cerebral blood flow; middle cerebral artery; supplements
Online: 23 February 2020 (13:05:55 CET)
Cerebral blood flow (CBF) decreases across the lifespan, and chronic conditions such as dementia and stroke accelerate this decline. Impaired CBF results in reduced delivery of oxygen and nutrients, which can damage the brain over time. Thus, there is a need to identify lifestyle interventions including diet and exercise to maintain CBF with aging and in the presence of chronic disease. In the present study, we used transcranial Doppler ultrasound to record middle cerebral artery velocity (MCAv), a surrogate measure of CBF, during moderate-intensity exercise in sedentary, cognitively-normal older adults (N = 90). A multiple linear regression model (F(4, 85) = 3.21, p = 0.02) showed self-reported omega-3 supplement use significantly moderated the association between age and mean exercising MCAv in these individuals (p = 0.01). Older age was associated with lower exercising MCAv in the group not taking omega-3 supplements, while exercising MCAv showed no decline with increasing age in the group who reported omega-3 supplement use. These findings suggest omega-3 supplementation may have an important role in the preservation of CBF with aging.
ARTICLE | doi:10.20944/preprints202009.0085.v1
Subject: Mathematics & Computer Science, Other Keywords: 3D+t modeling; coronary artery; non-rigid registration; cage deformation; 4D CT
Online: 4 September 2020 (07:36:01 CEST)
Cardiovascular-related diseases are one of the leading causes of death worldwide. An understanding of heart movement based on images plays a vital role in assisting the procedure in the postoperative and postoperative processes. In particular, if the shape information can be provided in real-time using the electrocardiogram(ECG) signal using this information, the heart’s movement information can be used for cardiovascular analysis and imaging guides during surgery. In this paper, we propose creating a 3D+t cardiac coronary artery model that is rendered in real-time according to the ECG signal. Hierarchical cage-based deformation modeling is used to generate mesh deformation used during the procedure according to the ECG signal. We match the blood vessel’s lumen obtained from the ECG-gated 3D+t CT angiography taken at the multiple cardiac phases to derive the optimal deformation. Splines for 3D deformation control points were used to continuously represent the obtained deformation at the multi-view according to the ECG signal. To verify the proposed method, we compared the manually segmented lumen and results of the proposed method for eight patients. The average distance and dice coefficient between the two models was 0.543mm and 0.735, respectively. The required time for registration of the 3D coronary artery model is 23.53 seconds/model. rendering speed to derive the model according to the ECG signal after generating the 3D+t model is faster than 120 FPS.
CASE REPORT | doi:10.20944/preprints202205.0005.v1
Subject: Medicine & Pharmacology, Other Keywords: skull base; high-flow bypass; sustentacular cell; endoscopic sinus surgery; internal carotid artery
Online: 4 May 2022 (12:22:23 CEST)
In the diagnosis of olfactory neuroblastoma (ONB), the presence of S-100–positive sustentacular cells surrounding the tumor is important; however, these are also present in normal nasal sinus epithelium. Although ONB often has a different final diagnosis, complete resection of the tumor has a good prognosis and minimally affects the patient's treatment plan. When the tumor extends around the internal carotid artery (ICA), complete resection is difficult due to the high risk of vascular injury; revascularization using a high-flow bypass can avoid this complication. In the present case, the tumor was located in the left sphenoid sinus and extended around the ICA. Preoperative biopsy tissue was positive for neuroendocrine markers and slightly positive for S-100 protein, leading to a diagnosis of ectopic ONB. High-flow bypass revascularization with trapping of the ICA allowed complete tumor resection. The postoperative histopathological diagnosis was neuroendocrine carcinoma, showing no S-100 protein–positive cells. There was no sign of recurrence two and a half years after surgery without additional treatment. This case demonstrates that the presence of S-100 protein–positive cells in ONB may be misleading. Although misdiagnosis of ectopic ONB should be anticipated, a complete resection of the tumor is an effective treatment strategy.
ARTICLE | doi:10.20944/preprints201812.0128.v1
Subject: Life Sciences, Other Keywords: middle cerebral artery occlusion (MCAO); MCPIP1; blood-brain barrier; inflammatory response; ischemia; metalloproteinases
Online: 11 December 2018 (10:49:54 CET)
Focal cerebral ischemia can lead to blood-brain barrier (BBB) breakdown, which is implicated in neuroinflammation and elevation of matrix metalloproteinases (MMPs). The role of the anti-inflammatory protein, monocyte chemotactic protein–induced protein 1 (MCPIP1) plays in the injury of BBB in stroke has not yet been reported. This study was conducted to identify and characterize the role MCPIP1 plays in BBB breakdown. Transient middle cerebral artery occlusion (MCAO) is induced in both wild-type and Mcpip1-/- mice for 2 hours of occlusion periods followed by reperfusion for 24 or 48 hours. BBB permeability was measured by FITC-dextran extravasation, MMP-9/3 expression was analyzed by western blot, and claudin-5 and zonula occludens-1 (ZO-1) were analyzed by immunohistochemistry and western blot. After MCAO in wild type mouse is induced, there is significantly increase in MCPIP1 mRNA and protein levels. Absence of MCPIP1 leaded to significant increase in FITC-dextran leakage in peri-infarct brain, significant upregulation of MMP-9, MMP-3 and reduced levels of tight junction components, claudin-5 and ZO-1 in the brain after MCAO. Our data demonstrate that absence of MCPIP1 exacerbates ischemia-induced blood-brain barrier disruption by enhancing the expression of matrix metalloproteinases and degradation of tight junction proteins. Overall data indicate that MCPIP1 is important protective role against BBB disruption in cerebral ischemia.
REVIEW | doi:10.20944/preprints202204.0057.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: atherosclerosis; biomechanics; border detection; coronary artery disease; optical coherence to-mography; stents; vulnerable plaque
Online: 7 April 2022 (08:13:34 CEST)
Coronary optical coherence tomography (OCT) is an intravascular, near-infrared light-based imaging modality capable of reaching axial resolutions of 10-20 µm. This resolution allows for accurate determination of high-risk plaque features, such as thin cap fibroatheroma; however, visualisation of morphological features alone still provides unreliable positive predictive capability for plaque progression or future major adverse cardiovascular events (MACE). Biomechanical simulation could assist in this prediction, but this requires extracting morphological features from intravascular imaging to construct accurate three-dimensional simulations of patients’ arteries. Extracting these features is a laborious process, often carried out manually by trained experts. To address this challenge, numerous techniques have emerged to automate these processes while simultaneously overcoming difficulties associated with OCT imaging, such as its limited penetration depth. This systematic review summarises advances in automated segmentation techniques from the past five years (2016-2021) with a focus on their application to the three-dimensional reconstruction of vessels and their subsequent simulation. We discuss four categories based on the feature being processed, namely: coronary lumen; plaque characteristics and subtypes; artery layers; and stents. Areas for future innovation are also discussed as well as their potential for future translation.
REVIEW | doi:10.20944/preprints202112.0363.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: Platelet; ACKR3/CXCR7; Thrombosis; Thrombo-inflammation; Anti-platelet therapy; Cardiovascular disease; Coronary artery disease
Online: 22 December 2021 (12:27:01 CET)
The manifold actions of the pro-inflammatory and regenerative chemokine CXCL12/SDF-1α are executed through the canonical GProteinCoupledReceptor CXCR4, and the non-canonical ACKR3/CXCR7. Platelets express CXCR4, ACKR3/CXCR7, and are a vital source of CXCL12/SDF-1α themselves. In recent years, a regulatory impact of the CXCL12-CXCR4-CXCR7 axis on platelet biogenesis i.e. megakaryopoiesis, thrombotic and thrombo-inflammatory ac-tions have been revealed through experimental and clinical studies. Platelet surface expression of ACKR3/CXCR7 is significantly enhanced following myocardial infarction (MI) in acute coro-nary syndrome (ACS) patients, also associated with improved functional recovery and progno-sis. The therapeutic implications of ACKR3/CXCR7 in myocardial regeneration and improved recovery following an ischemic episode, are well documented. Cardiomyocytes, cardi-ac-fibroblasts, endothelial lining of the blood vessels perfusing the heart, besides infiltrating platelets and monocytes, all express ACKR3/CXCR7. This review recapitulates ligand induced differential trafficking of platelet CXCR4-ACKR3/CXCR7 affecting their surface availability, and in regulating thrombo-inflammatory platelet functions and survival through CXCR4 or ACKR3/CXCR7. It emphasizes the pro-thrombotic influence of CXCL12/SDF-1α exerted through CXCR4, as opposed to the anti-thrombotic impact of ACKR3/CXCR7. Offering an innovative translational perspective, this review also discusses the advantages and challenges of utilizing ACKR3/CXCR7 as a potential anti-thrombotic strategy in platelet associated cardiovascular dis-orders, particularly in coronary artery disease (CAD) patients post-MI.
Subject: Mathematics & Computer Science, Applied Mathematics Keywords: blood flow, stenosed artery, K-L model, heat and mass transfer, finite difference scheme
Online: 20 March 2019 (16:49:24 CET)
A non-Newtonian fluid model is used to investigate the two-dimensional pulsatile blood flow through a tapered artery with a stenosis. The mixed convection effects of heat and mass transfer are also taken into account. By applying non-dimensionalization and radial coordinate transformation, we simplify the system in a tube. Under the finite difference scheme, numerical solutions are calculated for velocity, temperature concentration, resistance, impedance, wall shear stress and shearing stress at the stenosis throat. Finally, Quantitative analysis is carried out.
ARTICLE | doi:10.20944/preprints202209.0178.v1
Subject: Medicine & Pharmacology, Anesthesiology Keywords: chronic postoperative pain; erector spinae plane block; coronary artery bypass grafting; Neuropathic Pain Symptom Inventory
Online: 13 September 2022 (11:24:28 CEST)
Up to 56% of patients develop chronic postsurgical pain (CPSP) after coronary artery bypass grafting (CABG). CPSP can affect patients’ moods and decrease daily activities. The primary aim of this study was to investigate CPSP severity in patients following off-pump (OP)-CABG using the Neuropathic Pain Symptom Inventory (NPSI). This was a prospective cohort study conducted in a cardiac surgery department of a teaching hospital. Patients undergoing OP-CABG were enrolled in an erector spinae plane block (ESPB) group (n = 27) or a control (CON) group (n = 24). Before the induction of general anesthesia, ESPB was performed on both sides under ultrasound guidance using 0.375% ropivacaine. The secondary outcomes included cumulative oxycodone consumption, acute pain intensity, mechanical ventilation time, hospital length of stay, and postoperative complications. CPSP intensity was lower in the ESPB group than in the CON group 1, 3, and 6 months postsurgery (p < 0.001). Significant between-group differences were also observed in other outcomes, including postoperative pain severity, opioid consumption, mechanical ventilation time, and hospital length of stay in favor of the ESPB group. Preemptive ESPB appears to decrease the risk of CPSP development in patients undergoing OP-CABG. Reduced acute pain severity and shorter mechanical ventilation times and hospital stays should improve patients’ satisfaction and reduce perioperative complications.
REVIEW | doi:10.20944/preprints201912.0365.v1
Subject: Medicine & Pharmacology, Obstetrics & Gynaecology Keywords: Acute Coronary Syndrome; STEMI; Spontaneous Coronary Artery Dissection; NSTEMI; Vasospastic Angina; Preeclampsia; Eclampsia; Systemic Lupus Erythromatosus
Online: 27 December 2019 (10:41:42 CET)
In this study, we wanted to discuss the acute coronary syndromes in the pregnant womens which are very important for life ofthe fetus. Spontaneous coronary artery dissection and management, which is the most common cause of acute coronary syndrome in pregnant women is also discussed. About 300 articles were examined and 35 articles which published in high quality journals with high level of evidence were chosen and this review was prepared.
REVIEW | doi:10.20944/preprints202010.0011.v1
Subject: Keywords: Anterior spinal artery syndrome; Spinal cord Infarction; Aortic insufficiency; Aortic surgery; Spinal shock; Quadriplegia; Bowel-bladder incontinence
Online: 1 October 2020 (09:15:58 CEST)
As an uncommon cause of spinal cord infarction, anterior spinal cord syndrome can manifest with motor paralysis, loss of pain, and temperature sensation distal to the site of the lesion. The main pathogenesis of this syndrome is the disruption of blood flow in the anterior spinal artery. Mortality and morbidity differ with the etiology of the syndrome. So knowing the etiology of blood flow disruption is essential for patient management. This review article highlights the important clinical manifestation of Anterior spinal artery syndrome. Also describes etiology, pathogenesis, diagnosis, prognosis, possible management, and complications.
ARTICLE | doi:10.20944/preprints202210.0314.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: Aortic surgery; Aortic arch; Three-way cannulation approach; Carotid artery perfusion; Pressure-volume loop; Lumped parameter model; Software simulation; Cardiovascular modelling.; CARDIOSIM
Online: 20 October 2022 (14:19:25 CEST)
Aortic disease has a significant impact on quality of life. Involvement of the aortic arch requires preservation of blood supply to the brain during surgery. Deep hypothermic circulatory arrest is an established technique for this purpose although neurological injury remains high. Additional techniques have been used to reduce the risk although controversy still remains. A three-way cannulation approach, including both carotid arteries and the femoral artery or the ascending aorta, has been used successfully for aortic arch replacement and redo procedures. We have de-veloped circuits of the circulation to simulate blood flow during this type of cannulation set up. The aim is to analyse using CARDIOSIM© cardiovascular simulation platform, how the haemodynamic and energetic parameters are affected and the benefit derived with particular reference to the cerebral circulation.
ARTICLE | doi:10.20944/preprints202205.0400.v1
Subject: Biology, Physiology Keywords: Internal carotid artery sidewall aneurysm (ICASA); hemodynamic behaviors; computational fluid dynamics (CFD); pulsatile flow rate (PFR); bifurcated shunt ratio; wall shear stress (WSS); oscillatory shear index (OSI); time-averaged pressure (TAP)
Online: 30 May 2022 (11:38:31 CEST)
The pulsatile flow rate (PFR) in the cerebral artery system and shunt ratios in bifurcated arteries are two patient-specific parameters which may affect the hemodynamic characteristics on the pathobiology of cerebral aneurysms (CAs). Accordingly, a systematic study was employed to investigate the effects of the two parameters on hemodynamic characteristics in two internal carotid artery sidewall aneurysms (i.e., ICASA-1 and ICASA-2) models. Numerical results indicate larger PFRs can cause higher WSS in some local regions of the aneurysmal dome that may increase the probability of small/secondary aneurysms generation than under smaller PFRs. The low WSS and relatively high oscillatory shear index (OSI) could appear under a smaller PFR, which has the potential to cause aneurysmal sac growth and rupture. However, the variances in PFRs and bifurcated shunt ratios have rare impacts on the time-average pressure distributions on the aneurysmal sac, although a higher PFR can contribute more to the pressure increase in ICASA-1 dome due to the relatively stronger impingement by the redirected blood stream than in ICASA-2. Simulation results also present the variances of shunt ratios have rare impacts on the hemodynamic characteristics in sacs, mainly because the bifurcated location is not close enough to the sac in present models. Furthermore, it has been found that the vortex location plays a major role in the temporal and spatial distribution of the WSS on the luminal wall, varying significantly with the cardiac period.
REVIEW | doi:10.20944/preprints202111.0253.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: Cell therapy; chronic limb-threating ischemia; peripheral artery disease; diabetes; atherosclerosis obliterans; thromboangiitis obliterans; personalized medicine; artificial intelligence; machine learning; genome-wide association studies; transcriptome-wide association studies; clonal hematopoiesis of indeterminate potential.
Online: 15 November 2021 (11:18:43 CET)
Stem/progenitor cell transplantation is a potential novel therapeutic strategy to induce angiogenesis in ischemic tissue, which can prevent major amputation in patients with advanced peripheral artery disease (PAD). Thus, clinicians can use cell therapies worldwide to treat PAD. However, some cell therapy studies did not report beneficial outcomes. Clinical researchers suggested that classical risk factors and comorbidities may adversely affect the efficacy of cell therapy. Some studies have indicated that the response to stem cell therapy varies among patients even in those harboring limited risk factors. This suggested the role of undetermined risk factors, including genetic alterations, somatic mutations, and clonal hematopoiesis. Personalized stem cell-based therapy can be developed by analyzing individual risk factors. These approaches must consider several clinical biomarkers and perform studies (such as genome-wide association studies (GWAS)) on disease-related genetic traits and integrate the findings with those of transcriptome-wide association studies (TWAS) and whole-genome sequencing in PAD. Additional unbiased analyses with state-of-the-art computational methods, such as machine learning-based patient stratification, are suited for predictions in clinical investigations. The integration of these complex approaches into a unified analysis procedure for the identification of responders and non-responders before stem cell therapy, which can decrease treatment expenditure, is a major challenge to increase the efficacy of therapies.
ARTICLE | doi:10.20944/preprints201802.0165.v1
Subject: Medicine & Pharmacology, Clinical Neurology Keywords: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leuco encephalopathy (CADASIL); Carotid Endarterectomy (CEA); Modified Rankin Scale (MRS); Computed Tomography(CT); Tissue plasminogen activator (tPA); Diffusion weighted Imaging (DWI); Recognition of Stroke in the Emergency Room (ROSIER) scale; Magnetic resonance Imaging (MRI); Internal Carotid Artery (ICA)
Online: 26 February 2018 (11:46:47 CET)
In advanced world stroke is one of the disabling cause of death that can be managed with thrombolysis if presents early despite further risk of intracerebral haemorrhage. Secondary prevention is an important objective in ischaemic stroke where recurrence is very high with subsequent stroke. Carotid End Arterectomy impact a definitive and effective role for both symptomatic and asymptomatic carotid stenosis for secondary stroke prevention in selective cases. Thrombolysis is a potential primary management for certain group whereas carotid surgery employs secondary preventative measure in a specified ischaemic stroke group.