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Role of Streptokinase as a Thrombolytic Agent for Medical Applications
Published in Pankaj Bhatt, Industrial Applications of Microbial Enzymes, 2023
Hamza Rafeeq, Muhammad Anjum Zia, Asim Hussain, Ayesha Safdar, Muhammad Bilal, Hafiz M. N. Iqbal
Thrombosis is blood clot formation in the blood vessels, and this is actually the result of an imbalance of hemostasis and its inhibitors (Rizzoli et al., 2013). Changes in the blood vessels result in thrombosis, especially if the blood flow is slow (Kikkert et al., 2014). Atherosclerosis is due to changes in blood vessels. The plaques are protrusions in blood vessels, and these plaques are made up of lipids and collagens made up of smooth muscles (Tadayon et al., 2015). Different cells, such as free fatty acids, cholesterol, and scar tissues present in the arterial walls, make the arteries constrict, making it difficult for blood to flow to the heart. Chest pain is caused by slowed blood flow, and heart attack results from complete blockage of blood. And the most prominent cause of death in the developed countries is thrombosis. Forty-five percent of total deaths are due to vascular diseases in the United States (Ali et al., 2016). Lifestyle and diet changes prevent thrombosis. High plasma lipid levels are due to an imbalanced diet, lack of physical activity, high blood pressure, and cigarette smoking (Ali et al., 2016). Figure 14.1 represents the mechanism of thrombus formation in a circulatory system.
Reducing uncertainties in compensation for occupational diseases in construction using analytics
Published in Imriyas Kamardeen, Preventing Workplace Incidents in Construction, 2019
Cardiovascular diseases (CVD) refer to a variety of conditions that affect the heart and blood vessels (circulatory system), and are amongst the leading causes of death worldwide. These diseases are the results of a process called atherosclerosis, which is the build-up of fatty deposits (plaque) on the inside walls of arteries. Atherosclerosis can cause narrowing in, and possibly blockages of, arteries, which results in poor blood supply to vital parts of the body (Baker IDI 2011). Atherosclerosis can affect any artery in the body, including arteries in the heart, brain, arms, legs, pelvis and kidneys and, as a result, different diseases can develop based on which arteries are affected (University of Michigan Health System 2014). Poor blood flow to the heart is called coronary artery disease and can causes a heart attack (also referred to as ischaemic heart disease). Poor blood flow to the brain can cause a stroke (also known as cerebrovascular disease). Poor blood flow to the arms or legs is called peripheral artery disease (University of Ottawa Heart Institute 2011). The Australian Safety and Compensation Council (2008) also listed a few other diseases under the category of circulatory system diseases in TOOCS3.0 Classification, including: venous thromboembolism; hypertension (high blood pressure) and vibration white finger (Raynaud’s disease).
Cardiovascular system
Published in David A Lisle, Imaging for Students, 2012
Coronary artery disease is a diffuse disease of the coronary arteries characterized by atheromatous plaques. Plaques may cause stenosis of coronary arteries producing limitation of blood flow to the myocardium. During the development of atheromatous plaque, the external membranes of coronary arteries may expand outwards. As a result of this arterial remodelling phenomenon, significant coronary atherosclerosis may be present without narrowing of the vessel lumen (non-stenosing plaque). Rupture of atherosclerotic plaques with subsequent arterial thrombosis leads to acute cardiac events (acute cardiac syndrome), such as unstable angina, myocardial infarction and sudden death. Instability and rupture of atherosclerotic plaque is mediated by inflammatory factors, and may occur with stenosing or non-stenosing plaque.
Using intravascular ultrasound image-based fluid-structure interaction models and machine learning methods to predict human coronary plaque vulnerability change
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2020
Liang Wang, Dalin Tang, Akiko Maehara, Zheyang Wu, Chun Yang, David Muccigrosso, Mitsuaki Matsumura, Jie Zheng, Richard Bach, Kristen L. Billiar, Gregg W. Stone, Gary S. Mintz
Atherosclerotic plaque may rupture without warning, leading to drastic cardiovascular events such as heart attack and stroke (Naghavi et al. 2003). While plaque rupture could be identified during autopsy or by high-resolution imaging technology after the cardiovascular event happened, the clinical challenge is to predict upcoming plaque rupture and related critical events before they actually happen. One challenge for developing plaque rupture predictive methods is lack of actual in vivo plaque rupture cases and clinical event data which are needed to validate those methods. With 2–5% adverse event rate in one year, it is hard to get enough rupture cases as “ground truth” in a small-scale project (tracking 50 patients may only get 1–2 ruptured cases in vivo per year) (Stone et al. 2011). This makes it extremely difficult to quantify rupture-based plaque vulnerability, which is defined as the likelihood that a plaque would rupture. A solution to this problem is to find some measure as an alternative to quantify plaque vulnerability based on plaque morphological features related to plaque rupture.
The effect of hemodynamic parameters in patient-based coronary artery models with serial stenoses: normal and hypertension cases
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2020
K. E. Hoque, M. Ferdows, S. Sawall, E. E. Tzirtzilakis
Computational Hemodynamics (CHD) parameters play a vital role in assessing the physiological conditions in cardiovascular abnormalities (Cademartiri et al. 2017). Cardiovascular diseases such as atherosclerosis occur due to the result of plaque formation and accumulation of fatty substance inside the vessel wall (Morris et al. 2013). Multiple sequential stenoses (MSS) or coronary aneurysm in a single branch of a coronary artery are responsible for uncertain prognosis of invasive procedures (Bit and Chattopadhay 2018). The hemodynamic significance of each stenosis is influenced by other stenoses emphasizing the importance to evaluate the CHD parameters of each coronary lesion (Ju and Gu 2019). The derived parameters offer the possibility to investigate local atherosclerotic plaque conditions in coronary arteries at a level of detail that is not always accessible with experimental techniques (Kamangar et al. 2017; Seo et al. 2019). Li et al. (2017) demonstrated that there is a linear relationship between flow and pressure in MSS models within idealized coronary models and in in-vitro experiments. They also illustrated that results of simulations of pulsatile and steady are quantitative similar but computational demands highly vary. In this study, we used coronary computed tomography angiography (CCTA) image-based 3D right coronary artery (RCA) models for CHD simulations. The used open source set-up provided us all relevant CHD parameters. In addition, we explored the flow-pressure relation in patient-based 3D models with verified MSS.
Mathematical investigation of drug dispersion in the blood flow through Stenotic-Aneurysm tapered blood vessel
Published in International Journal of Modelling and Simulation, 2023
J V Ramana Reddy, Hojin Ha, S Sundar
The blood vessels are the blood carriers from the heart to the body organs (arteries) and from body organs to the heart (veins). The general appearance of the arteries is rounded, while veins are irregular and often collapse. Compared to arteries, veins are thin-walled vessels with a large and irregular lumen. The veins contain approximately 64% of the total body blood volume, which is a part of 84% of the systemic circulation. The heart comprises 7% of the blood, while the rest 9% is circulating through pulmonary circulation vessels. Vascular disease includes the diseases of arteries, veins, and lymph vessels. Atherosclerosis is a condition where the lumen diameter of the blood vessel disease may occur in the blood vessels in the heart and also in the blood vessels outside the heart. The composition is the build-up of fat and cholesterol deposits, called plaque, on the inside walls. Over time, the build-up narrows the artery. Eventually, the narrowed artery allows less blood to flow, and further, a pathological condition called Ischemia can occur. Ischemia is an inadequate blood flow to the body’s tissue. The stenosis-aneurysm models (eqns (3)-(10)) in the present study resemble a pathological vascular disease. In the current model, one can notice that for the qualitative analysis considering the size of the stenosis and (or) aneurysm is quite useful instead of relying on the height of the stenosis. Therefore, the percentage of the region occupied by the plaque, aneurysm out of the total lumen area in that segment is calculated by using the following empirical relation,