Atherosclerosis,describe its effects on the Heart?

what happens to the Heart when it has Atherosclerosis

If the fibrous cap separating a soft atheroma from the bloodstream within the artery ruptures, tissue fragments are exposed and released, and blood enters the atheroma within the wall and sometimes results in a sudden expansion of the atheroma size. Tissue fragments are very clot-promoting, containing collagen and tissue factor; they activate platelets and activate the system of coagulation. The result is the formation of a thrombus (blood clot) overlying the atheroma, which obstructs blood flow acutely. With the obstruction of blood flow, downstream tissues are starved of oxygen and nutrients. If this is the myocardium (heart muscle), angina (cardiac chest pain) or myocardial infarction (heart attack) develops.

Atherosclerosis (ath"er-o-skleh-RO'sis) comes from the Greek words athero (meaning gruel or paste) and sclerosis (hardness). It's the name of the process in which deposits of fatty substances, cholesterol, cellular waste products, calcium and other substances build up in the inner lining of an artery. This buildup is called plaque. It usually affects large and medium-sized arteries. Some hardening of arteries often occurs when people grow older.

Plaques can grow large enough to significantly reduce the blood's flow through an artery. But most of the damage occurs when they become fragile and rupture. Plaques that rupture cause blood clots to form that can block blood flow or break off and travel to another part of the body. If either happens and blocks a blood vessel that feeds the heart, it causes a heart attack. If it blocks a blood vessel that feeds the brain, it causes a stroke.
Atherosclerosis is a slow, complex disease that typically starts in childhood and often progresses when people grow older. In some people it progresses rapidly, even in their third decade. Many scientists think it begins with damage to the innermost layer of the artery. This layer is called the endothelium (en"do-THE'le-um). Causes of damage to the arterial wall include:

elevated levels of cholesterol and triglyceride (tri-GLIS'er-id) in the blood
high blood pressure.
tobacco smoke
diabetes

Tobacco smoke greatly worsens atherosclerosis and speeds its growth in the coronary arteries, the aorta and arteries in the legs. (The coronary arteries bring blood to the heart muscle; the aorta is the large vessel that the heart pumps blood through to the body.)

Because of the damage to the endothelium, fats, cholesterol, platelets, cellular waste products, calcium and other substances are deposited in the artery wall. These may stimulate artery wall cells to produce other substances that result in further buildup of cells.

These cells and surrounding material thicken the endothelium significantly. The artery's diameter shrinks and blood flow decreases, reducing the oxygen supply. Often a blood clot forms near this plaque and blocks the artery, stopping the blood flow.

the arteries become clogged with plaque build up ..through the years...
it can be diet, or genetic.
when the arteries become clogged, blood flow to the heart is lessened. since the heart is a muscle, when blood flow is restricted, there is less oxygenation ( oxygen is acrried in blood)
with less oxygen..the muscle begins to ache.....chest pain.
people can live for many years with ASCHLD ( arterioschlerotic heart disease) but the quality of their life will be limited.

This is the deposition of atheroma (fat including cholesterol etc.) in the inside layer of the blood vessels thus causing narrowing and hardening (loss of elasticity) of the blood vessels concerned.

1.When it occurs in the coronary vessels the blood supply of the heart muscle decreases and may even be stopped altogether. This manifests itself by a spectrum of diseases ranging from an angina pectoris attack to a most severe fatal myocardial infarction.

2.When the atherosclerosis is widespread in the systemic arteries
the narrowing causes an increasing peripheral resistance thus increasing the blood pressure.[ Blood Pressure= Cardiac Output X peripheral resistance].
With an uncontrolled high blood pressure, hypertensive heart disease follows. This include cardiac hypertrophy, Myocardial ischaemia & heart failure.

Hope this answers your question

Basically plaques or deposits of cholesterol begin to be laid down in the wall of the blood vessels. As this increases the diameter of the vessels reduces. The longer the plaques are in place the more crisp and brittle they become.

This causes three potential problems.

Firstly, because the vessels are reduced in size, the blood flow through them becomes gradually less and less. In the case of arteries to the heart there is, except in the late stages, enough blood coming through the arteries to supply the heart muscle when the patient is at rest. When he becomes more active, or excited, or when another part of the body demands more blood, usually the bowel, to help it digest a large meal, demand for blood to supply the heart muscle exceeds demand. When this happens the patient feels pain in the heart. This is called angina pectoris. (Angina for short.)

Secondly, as the arteries become narrower and their walls rougher, as the blood flows through them, platelets, (tiny cell fragments in the blood which are designed to plug holes in blood vessels when they become damaged) may begin to stick to the walls as well. These may form a bigger and bigger clot, which blocks the artery completely.

Thirdly, a chunk of the brittle cholesterol may break off from the wall of an artery, as is passed with the blood, further down the artery, it may become stuck in a narrower vessel again blocking the artery.

These blocked arteries can cause areas of the heart muscle to have no blood reaching them at all .This is a heart attack. If the area which looses it's blood supply is large enough, the heart cannot continue to function and the patient dies.

Exactly the same process can occure in the brain, here it causes a stroke, or in the leg where is causes limb death or gangrene.

Atherosclerosis occurs in arteries supplying blood to heart , they become thick, hardened and narrowed from plaque growths within the arteries, reducing blood flow to heart muscle . Atherosclerosis is a progressive disease and will in time reduce nourishment to heart sufficient to cause heart failure.