What happens during coronary circulation?What happens when coronary arteries become blocked?

Answer 1

when the coronary arteries are blocked, u will have a heart attack, because the supply of oxygent that need by hearts can`t be delivered.

Answer 2

The coronary arteries supply blood to the heart, and unlike all other arteries, the coronary arteries receive their blood supply during diastole. This is due to the location of the openings for the coronary arteries at the base of the aorta (near the aortic valve, which obscures these openings when the valve is open). If a coronary artery becomes blocked, the part of the heart muscle that is supplied by that artery will become hypoxic and die (heart attack) This should provide a starting point for your homework assignment.

Answer 3

The coronary circulation consists of the blood vessels that supply blood to, and remove blood from, the heart muscle itself. Although blood fills the chambers of the heart, the muscle tissue of the heart, or myocardium, is so thick that it requires coronary blood vessels to deliver blood deep into the myocardium. The vessels that supply blood high in oxygen to the myocardium are known as coronary arteries. The vessels that remove the deoxygenated blood from the heart muscle are known as cardiac veins.

The coronary arteries that run on the surface of the heart are called epicardial coronary arteries. These arteries, when healthy, are capable of autoregulation to maintain coronary blood flow at levels appropriate to the needs of the heart muscle. These relatively narrow vessels are commonly affected by atherosclerosis and can become blocked, causing angina or a heart attack.

Answer 4

The heart itself needs to be supplied with blood. This is delivered by the two coronary arteries and their branches. The right coronary artery takes its origin from the aorta just distal to the aortic valve and appears on the surface of the heart between the pulmonary trunk and the auricle of the right atrium. Major branches of the right coronary artery include its marginal branch, posterior interventricular branch, and AV nodal branch. The right coronary artery is distributed to the right atrium, right ventricle, and variable portions of the left atrium and left ventricle.

The left coronary artery also arises from the base or ascending portion of the aorta. It is at first located between the pulmonary trunk and auricle of the left atrium. Major branches of the left coronary artery include its anterior interventric-ular branch and its circumflex branch. Thus, the left coronary artery supplies both ventricles, the inter-ventricular septum and the left atrium.

Most of the blood supplied by the coronary arteries is returned to the right atrium by way of the coronary sinus. Tributaries of the coronary sinus include the great cardiac vein, middle cardiac vein, and small cardiac vein. As mentioned in the pages on the structure of the heart, numerous microscopic veins, the venae cordis minimae, open directly into the heart chambers.


Coronary circulation disorders

Coronary artery disease
Coronary artery disease is a type of heart disease. The coronary arteries are blood vessels that carry blood and oxygen to the heart muscle. When these arteries become clogged with fatty deposits called plaque, it is called coronary artery disease (CAD). CAD is sometimes called coronary heart disease (CHD). Clogged arteries can keep the heart from getting enough blood and oxygen and can cause chest pain (angina). If a blood clot forms, it can suddenly cut off blood flow in the artery and cause a heart attack.

Atherosclerosis
Atherosclerosis is a type of arteriosclerosis caused by a build-up of plaque in the inner lining of an artery. Plaque is made up of deposits of fatty substances, cholesterol, cellular waste products, calcium, and fibrin, and can develop in medium or large arteries. The artery wall becomes thickened and looses its elasticity. Atherosclerosis progresses with a gradual build-up of plaque or thickening of the inside of the walls of the artery, which causes a decrease in the amount of blood flow, and a decrease in the oxygen supply to the vital body organs and extremities.

Restenosis
Restenosis is a re-narrowing or blockage of an artery at the same site where treatment, such as a balloon angioplasty or stent procedure, has already taken place. Restenosis literally means the reoccurrence of stenosis. This is usually restenosis of an artery, or other blood vessel, but possibly any hollow organ that has been "unblocked". This term is common in vascular surgery, cardiac surgery or interventional cardiology following angioplasty, all branches of medicine that frequently treat stenotic lesions.

Acute coronary syndrome
Acute coronary syndrome is a spectrum of conditions involving chest discomfort or other symptoms caused by lack of oxygen to the heart muscle (the myocardium). The unification of these manifestations of coronary artery disease under a single term reflects the understanding that these are caused by a similar pathophysiology (sequence of pathologic events) characterized by erosion, fissuring, or rupture of a pre-existing plaque, leading to thrombosis (clotting) within the coronary arteries and impaired blood supply to the heart muscle.

Angina
Angina, also called angina pectoris, is discomfort or pain in the chest that happens when not enough oxygen-rich blood reaches the muscle cells of the heart. Angina is not a disease, but a symptom of a more serious condition, usually coronary artery disease, an illness in which the vessels that supply blood to the heart become narrow or blocked. Coronary artery disease is usually caused by atherosclerosis. Although angina most commonly affects males who are middle-aged or older, it can occur in both sexes and in all age groups.

Heart attack (myocardial infarction)
A heart attack (also known as a myocardial infarction) is the death of heart muscle from the sudden blockage of a coronary artery by a blood clot. Coronary arteries are blood vessels that supply the heart muscle with blood and oxygen. Blockage of a coronary artery deprives the heart muscle of blood and oxygen, causing injury to the heart muscle. Injury to the heart muscle causes chest pain and pressure. If blood flow is not restored within 20 to 40 minutes, irreversible death of the heart muscle will begin to occur. Muscle continues to die for 6-8 hours.

Answer 5

Heart Attacks, Strokes, even death if not treated immediately.