Atherosclerosis is a disease characterized by the deposition of fatty substances called plaques in the walls of medium and large arteries. Depending on which arteries are affected, it can lead to leg pain, erectile dysfunction, cardiovascular disease and heart attack or stroke. It is the main cause of death in developed countries. The disease often starts in childhood and the arteries become clogged over many years, initially without symptoms.Mechanism of the disease High blood pressure, high cholesterol, smoking, diabetes, sedentary life style, hormone status and age are all risk factors for atherosclerosis. These factors conspire to cause tears to the lining of the medium and large arteries, which results in fatty deposits, inflammation, and ultimately narrowing of the afflicted arteries. High blood pressure provides the shear force to produce tears in the fragile endothelium, the lining of the arteries. Cholesterol migrates into these torn sections when concentrations of LDL, or low density lipoprotein are high. Smoking has a direct toxic effect on the arterial wall, causing an inflammatory response. Exercise modifies many of these risk factors, ultimately lowering the inflammatory response of the arterial walls. Hormones, especially the presence of estrogen, has a healing effect on the arterial walls. The resident cells interpret this as an intrusion, "call for help", and inflammation results. Immune cells called monocytes circulating in the blood enter the artery wall, turn into macrophages and ingest the LDL particles, thereby turning into large "foam cells". The inflammation also causes a fibrous cap to be formed between the fatty deposits and the artery. These capped fatty deposits (called atheromas) narrow the blood vessel. This can lead to narrowing (stenosis) of the artery. The atheromas are fragile. When they rupture, a partial blockage can be quickly converted into a complete obstruction, resulting in a heart attack or stroke, depend ...

Category: Heart and Vascular

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• Coronary heart disease Pheeds Home | More Coronary heart disease articles & pheeds            

  Coronary heart disease

  Coronary heart disease (CHD), also called coronary artery disease and atherosclerotic heart disease, may be caused by inflammation of the lining of the arteries which allows atheromatous plaquess (caused by the buildup of cholesterol in the vessel wall) to form, limiting blood flow to the heart muscle. Table of contents 1 Pathophysiology 2 Angina 3 Prevention Pathophysiology Limitation of blood flow to the heart causes ischemia (cell starvation secondary to a lack of oxygen) of the myocardial cells. When myocardial cells die from lack of oxygen, this is called a myocardial infarction (commonly called a heart attack), and leads to heart muscle damage and later scarring. Myocardial infarction can resu ...

Category: Heart and Vascular

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• Lipoprotein Pheeds Home | More Lipoprotein articles & pheeds            

  Lipoprotein

  A lipoprotein is a biochemical assembly that contains both proteins and lipids and may be structural or catalytic in function. Lipoproteins may be enzymes, proton pumps, ion pumps, or some combination of these functions. Examples include the high density and low density lipoproteins of the blood and the transmembrane proteins of the mitochondrion and the chloroplast. The lipids are often an essential part of the complex, even if they seem to have no catalytic activity themselves. To isolate ...

Category: Cholesterol News

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• Low density lipoprotein Pheeds Home | More Low density lipoprotein articles & pheeds            

  Low density lipoprotein

  Low-density lipoprotein (LDL) is a lipoprotein that carries cholesterol around the body, for use by various cells. Because LDL transports cholesterol to the arteries, increased levels are associated with atherosclerosis, and thus myocardial infarctions and strokes. This is why cholesterol inside LDL lipoproteins is called bad cholesterol. LDL is formed as VLDL lipoproteins lose triglyceride, and become smaller and denser containing a higher proportion of cholesterol. Recommended range The American Heart Association provides a set of guidelines for fasting LDL levels and risk for heart disease. ; Less than 100 Category: Cholesterol News

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• High density lipoprotein Pheeds Home | More High density lipoprotein articles & pheeds            

  High density lipoprotein

  High density lipoproteins (HDL) are a class of lipoproteins that carry cholesterol from the body's tissues to the liver. Because HDL can remove cholesterol from the arteries, and transport it back to the liver for excretion, it is seen as a "good" lipoprotein. When measuring cholesterol, any contained in HDL particles is not a threat to the body's cardiovascular health. (In contrast to "bad" LDL cholesterol.) HDL are the smallest and densest lipoproteins, and are composed of a high proportion of protein. The liver synthesises these lipoproteins as empty proteins and they pick up cholesterol and increase in size as the circulate through the bloodstream. Men tend to have noticably lower HDL levels than women (men also have an increased risk of heart disease). Epidemiological studies show that high concentrations of HDL (over 60 mg/dL) have protective value against cardiovascular diseases (such as ischemic Category: Cholesterol News

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• Ischaemic heart disease Pheeds Home | More Ischaemic heart disease articles & pheeds            

  Ischaemic heart disease

  Ischaemic heart disease is a disease characterized by reduced blood supply to the heart. It is the most common cause of death in most western countries. Ischaemia means a "reduced blood supply". The coronary arteries supply blood to the heart muscle and no alternative blood supply exists, so a blockage in the coronary arteries reduces the supply of blood to heart muscle. Most ischaemic heart disease is caused by atherosclerosis. What is it?
  • Initially there is narrowing of coronary arteries causing angina.
  • The narrowing is mostly caused by fatty plaques lining the wall of the artery.
  • Sometimes a fatty plaque will rupture leading to a heart attack. (Heart attacks caused by simple narrowing are relatively uncommon).
  • A he ...

Category: Heart and Vascular

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