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Arterial Stiffness
Arterial stiffness occurs as a consequence of biological aging, arteriosclerosis and genetic disorders, such as Marfan, Williams, and Ehlers-Danlos syndromes. Inflammation plays a major role in arteriosclerosis and arterial stiffness. Increased arterial stiffness is associated with an increased risk of cardiovascular events such as myocardial infarction, hypertension, heart failure, and stroke. The World Health Organization identified cardiovascular disease as the leading cause of death globally in 2019. Degenerative changes that occur with age in the walls of large elastic arteries are thought to contribute to increased stiffening over time, including the disruption of lamellar elastin structures within the wall, possibly due to repeated cycles of mechanical stress; inflammation; changes in arterial collagen proteins, partially as a compensatory mechanism against the loss of arterial elastin and partially due to fibrosis; and crosslinking of adjacent collagen fibers by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Senescence
Senescence () or biological aging is the gradual deterioration of Function (biology), functional characteristics in living organisms. Whole organism senescence involves an increase in mortality rate, death rates or a decrease in fecundity with increasing age, at least in the later part of an organism's biological life cycle, life cycle. However, the resulting effects of senescence can be delayed. The 1934 discovery that calorie restriction can Life extension, extend lifespans by 50% in rats, the existence of species having negligible senescence, and the existence of potentially immortal organisms such as members of the genus ''Hydra (genus), Hydra'' have motivated research into Life extension, delaying senescence and thus age-related diseases. Rare human mutations can cause accelerated aging diseases. Environmental Gerontogens, factors may affect aging – for example, overexposure to ultraviolet radiation accelerates skin aging. Different parts of the body may age at different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Advanced Glycation Endproducts
Advanced glycation end-products (AGEs) are proteins or lipids that become glycated as a result of exposure to sugars. They are a bio-marker implicated in aging and the development, or worsening, of many degenerative diseases, such as diabetes, atherosclerosis, chronic kidney disease, and Alzheimer's disease. Dietary sources Animal-derived foods that are high in fat and protein are generally AGE-rich and are prone to further AGE formation during cooking. However, only low molecular weight AGEs are absorbed through diet, and vegetarians have been found to have higher concentrations of overall AGEs compared to non-vegetarians. Therefore, it is unclear whether dietary AGEs contribute to disease and aging, or whether only endogenous AGEs (those produced in the body) matter. This does not free diet from potentially negatively influencing AGE, but potentially implies that dietary AGE may deserve less attention than other aspects of diet that lead to elevated blood sugar levels and format ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventricular Remodelling
In cardiology, ventricular remodeling (or cardiac remodeling) refers to changes in the size, shape, structure, and function of the heart. This can happen as a result of exercise (physiological remodeling) or after injury to the heart muscle (pathological remodeling). The injury is typically due to acute myocardial infarction (usually transmural or ST segment elevation infarction), but may be from a number of causes that result in increased pressure or volume, causing pressure overload or volume overload (forms of strain) on the heart. Chronic hypertension, congenital heart disease with intracardiac shunting, and valvular heart disease may also lead to remodeling. After the insult occurs, a series of histopathological and structural changes occur in the left ventricular myocardium that lead to progressive decline in left ventricular performance. Ultimately, ventricular remodeling may result in diminished contractile ( systolic) function and reduced stroke volume. Physiological remod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Left Ventricular Hypertrophy
Left ventricular hypertrophy (LVH) is thickening of the heart muscle of the left ventricle of the heart, that is, left-sided ventricular hypertrophy and resulting increased left ventricular mass. Causes While ventricular hypertrophy occurs naturally as a reaction to aerobic exercise and strength training, it is most frequently referred to as a pathological reaction to cardiovascular disease, or high blood pressure. It is one aspect of ventricular remodeling. While LVH itself is not a disease, it is usually a marker for disease involving the heart. Disease processes that can cause LVH include any disease that increases the afterload that the heart has to contract against, and some primary diseases of the muscle of the heart. Causes of increased afterload that can cause LVH include aortic stenosis, aortic insufficiency and hypertension. Primary disease of the muscle of the heart that cause LVH are known as hypertrophic cardiomyopathies, which can lead into heart failure. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stroke Volume
In cardiovascular physiology, stroke volume (SV) is the volume of blood pumped from the ventricle (heart), ventricle per beat. Stroke volume is calculated using measurements of ventricle volumes from an Echocardiography, echocardiogram and subtracting the volume of the blood in the ventricle at the end of a beat (called end-systolic volume) from the volume of blood just prior to the beat (called end-diastolic volume). The term ''stroke volume'' can apply to each of the two ventricles of the heart, although when not explicitly stated it refers to the left ventricle and should therefore be referred to as left stroke volume (LSV). The stroke volumes for each ventricle are generally equal, both being approximately 90 mL in a healthy 70-kg man. Any persistent difference between the two stroke volumes, no matter how small, would inevitably lead to venous congestion of either the systemic or the pulmonary circulation, with a corresponding state of hypotension in the other circulatory sys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microcirculation
The microcirculation is the circulation of the blood in the smallest blood vessels, the microvessels of the microvasculature present within organ tissues. The microvessels include terminal arterioles, metarterioles, capillaries, and venules. Arterioles carry oxygenated blood to the capillaries, and blood flows out of the capillaries through venules into veins. In addition to these blood vessels, the microcirculation also includes lymphatic capillaries and collecting ducts. The main functions of the microcirculation are the delivery of oxygen and nutrients and the removal of carbon dioxide (CO2). It also serves to regulate blood flow and tissue perfusion, thereby affecting blood pressure and responses to inflammation which can include edema (swelling). Most vessels of the microcirculation are lined by flattened cells of the endothelium and many of them are surrounded by contractile cells called pericytes. The endothelium provides a smooth surface for the flow of blood and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Windkessel Effect
Windkessel effect (German: Windkesseleffekt) is a term used in medicine to account for the shape of the arterial blood pressure waveform in terms of the interaction between the stroke volume and the compliance of the aorta and large elastic arteries (Windkessel vessels) and the resistance of the smaller arteries and arterioles. Windkessel when loosely translated from German to English means 'air chamber', but is generally taken to imply an ''elastic reservoir''. The walls of large elastic arteries (e.g. aorta, common carotid, subclavian, and pulmonary arteries and their larger branches) contain elastic fibers, formed of elastin. These arteries distend when the blood pressure rises during systole and recoil when the blood pressure falls during diastole. Since the rate of blood entering these elastic arteries exceeds that leaving them via the peripheral resistance, there is a net storage of blood in the aorta and large arteries during systole, which discharges during diastole ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leukoaraiosis
Leukoaraiosis is a particular abnormal change in appearance of white matter near the lateral ventricles. It is often seen in aged individuals, but sometimes in young adults. On MRI, leukoaraiosis changes appear as white matter hyperintense, hyperintensities (WMHs) in T2 FLAIR images. On CT scans, leukoaraiosis appears as hypodense periventricular white-matter lesions. The term "leukoaraiosis" was coined in 1986 by Vladimir Hachinski, Hachinski, Potter, and Merskey as a descriptive term for rarefaction ("araiosis") of the white matter, showing up as decreased density on CT and increased signal intensity on T2/FLAIR sequences (white matter hyperintensities) performed as part of MRI brain scans. These white matter changes are also commonly referred to as periventricular white matter disease, or white matter hyperintensities (WMH), due to their bright white appearance on Magnetic resonance imaging#How MRI works, T2 MRI scans. Many patients can have leukoaraiosis without any associat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diabetes Mellitus
Diabetes mellitus, commonly known as diabetes, is a group of common endocrine diseases characterized by sustained hyperglycemia, high blood sugar levels. Diabetes is due to either the pancreas not producing enough of the hormone insulin, or the cells of the body becoming unresponsive to insulin's effects. Classic symptoms include polydipsia (excessive thirst), polyuria (excessive urination), polyphagia (excessive hunger), Weight loss#Unintentional, weight loss, and blurred vision. If left untreated, the disease can lead to various health complications, including disorders of the Cardiovascular disease, cardiovascular system, Diabetic retinopathy, eye, Diabetic nephropathy, kidney, and Diabetic neuropathy, nerves. Diabetes accounts for approximately 4.2 million deaths every year, with an estimated 1.5 million caused by either untreated or poorly treated diabetes. The major types of diabetes are Type 1 diabetes, type 1 and Type 2 diabetes, type 2. The most common treatment for ty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kidney Failure
Kidney failure, also known as renal failure or end-stage renal disease (ESRD), is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney failure is classified as either acute kidney failure, which develops rapidly and may resolve; and chronic kidney failure, which develops slowly and can often be irreversible. Symptoms may include leg swelling, feeling tired, vomiting, loss of appetite, and confusion. Complications of acute and chronic failure include uremia, hyperkalemia, and volume overload. Complications of chronic failure also include heart disease, high blood pressure, and anaemia. Causes of acute kidney failure include low blood pressure, blockage of the urinary tract, certain medications, muscle breakdown, and hemolytic uremic syndrome. Causes of chronic kidney failure include diabetes, high blood pressure, nephrotic syndrome, and polycystic kidney diseas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aorta
The aorta ( ; : aortas or aortae) is the main and largest artery in the human body, originating from the Ventricle (heart), left ventricle of the heart, branching upwards immediately after, and extending down to the abdomen, where it splits at the aortic bifurcation into two smaller arteries (the common iliac artery, common iliac arteries). The aorta distributes Oxygen saturation (medicine), oxygenated blood to all parts of the body through the systemic circulation. Structure Sections In anatomical sources, the aorta is usually divided into sections. One way of classifying a part of the aorta is by anatomical compartment, where the thoracic aorta (or thoracic portion of the aorta) runs from the heart to the thoracic diaphragm, diaphragm. The aorta then continues downward as the abdominal aorta (or abdominal portion of the aorta) from the diaphragm to the aortic bifurcation. Another system divides the aorta with respect to its course and the direction of blood flow. In this s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moens–Korteweg Equation
In biomechanics, the Moens–Korteweg equation models the relationship between wave speed or pulse wave velocity (PWV) and the incremental elastic modulus of the arterial wall or its distensibility. The equation was derived independently by Adriaan Isebree Moens and Diederik Korteweg. It is derived from Newton's second law of motion, using some simplifying assumptions, and reads: :PWV = \sqrt The Moens–Korteweg equation states that PWV is proportional to the square root of the incremental elastic modulus, (''E''inc), of the vessel wall given constant ratio of wall thickness, ''h'', to vessel radius, ''r'', and blood density, ρ, assuming that the artery wall is isotropic In physics and geometry, isotropy () is uniformity in all orientations. Precise definitions depend on the subject area. Exceptions, or inequalities, are frequently indicated by the prefix ' or ', hence '' anisotropy''. ''Anisotropy'' is also ... and experiences isovolumetric change with pulse pressure. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
