Deaths due to cardiovascular diseases constitute half of all deaths in developed countries. 75% of heart patients have atherosclerotic coronary artery diseases. In the USA, 600 thousand people die every year from coronary heart disease, half of them suddenly. It is four times more common in men than in women. The risk increases in post-menopausal women. Coronary artery disease is more common in men between the ages of 50-60 and in women between the ages of 60-70
Anatomy of the Coronary Arteries
There are 2 main coronary arteries that feed the heart. While the right and left main coronary arteries, the left anterior descending artery (LAD)courses on the front of the left ventricle, the circumflex (Cx)artery courses behind the heart. There are interconnections between Coronary Arteries. The right coronary artery supplies the right ventricle. In 90% of people, the right coronary artery is more prominent. The shorter trunk of the left main coronary artery is more prone to atherosclerosis. The left main coronary artery immediately divides into two branches: the left anterior descending branch and the circumflex branches.
Blood flow in the coronary vessels occurs mainly during the relaxation period of the heart, called the diastole period. Coronary vessels, like other vessels, consist of three layers consisting of intima, muscular layer and adventitia.
Approximately 75% of the coronary venous return. It is provided by a structure called "coronary sinus". This vessel opens directly to the right atrium.
Coronary Artery Diseases Due to narrowing and occlusions in the coronary arteries, permanent or temporary damage may occur to the heart muscle fed by these vessels.
Today, coronary arteries are the most common. As a result, atherosclerosis and subsequent ischemic heart disease occur. Atherosclerosis develops most commonly in the Crux region of the right coronary artery, and second most frequently in areas close to the center of the LAD. The third most common location of the disease is the section between the origin of the right coronary artery and its marginal branch. Atherosclerosis typically occurs in multiple regions and often in more than one artery.
Coronary artery disease. The reasons that cause heart muscle malnutrition and related heart muscle nutritional disorders are as follows.
1-Atherosclerosis (99%)
2-Arteritis (Systemic lupus erythematosus, Pan arteritis nodosa, Takayasu .)
3-Embolism
4 -Thickening of the coronary artery (Amyloidosis, radiation)
5-Other causes (spasm, aortic dissection)
6-Congenital coronary artery diseases (Arteriovenous fistulas, coronary artery outflow anomalies)
Sometimes coronary artery disease can occur without classical risk factors. Researchers are also studying some other factors.
C-reactive protein. Your liver produces C-reactive protein(CRP)in response to an infection or injury. CRP is also produced by muscle cells inside the coronary artery. CRP, is a general marker of inflammation that plays a central role in atherosclerosis,
Homocystin. Homocystin is an amino acid that the body uses to make proteins necessary to build and maintain tissues. However, excessive amounts of homocystin increase the risk of coronary artery disease.
Fibrinogen. It is a protein that plays an important role in blood clotting. But excessive amounts cause platelets to clump, platelets are the cells responsible for blood clotting. This causes clot formation within the arteries and causes coronary ischemia and heart attack. Fibrinogen can also trigger the inflammation that accompanies atherosclerosis.
Lipoprotein (a). When cholesterol particles attach to a specific protein, they form low-density lipoproteins (LDL) . The protein carried by lipoproteins impairs the body's ability to dissolve blood clots. High levels of lipoprotein are associated with increased cardiovascular disease, including coronary disease and heart attack.
Atherosclerosis
Fat accumulations are the precursor lesions of atherosclerosis, which is the most common cause of coronary artery diseases. and fibrous plaques. Atherosclerosis and narrowing of the coronary vessels develop slowly, without symptoms, for years. narrow down It is caused not only by the mass of the atherosclerotic plaque but also by the deterioration of the vasodilatory functions of the vessel wall
Atherosclerosis is a pathological disease that occurs due to the accumulation of lipid particles in the vessel wall and blocks the lumen of the vessels, preventing normal blood flow. It is a process. Fat accumulations are the earliest sign of atherosclerosis, observed even in children under the age of 3.
Fibrous plaque is the most important pathological lesion of atherosclerosis and is the source of the clinical findings seen in the disease. If the plaque causes a blockage of 50% or more in the vessel, resistance occurs, a pressure difference occurs and malnutrition develops. Different complications such as calcification, clot formation, bleeding into the plaque and aneurysm may later develop in the fibrous plaque.
Although there is no clear and specific etiology, it is known that various factors play a role in the etiology of atherosclerosis. Atherosclerosis has reversible risk factors such as smoking, hypertension, diabetes, high cholesterol, inactivity, oral contraceptive use, alcohol, obesity, stressful personality, or irreversible risk factors such as aging, male gender, family history of coronary artery disease under 55 years of age. A bacterium called Chlamydia pneumoniae has emerged as an important risk factor in recent years, especially in patients with suppressed defense systems.
It is known that early atherosclerosis occurs in people with higher than normal blood homocysteine levels. When two risk factors are together, the risk of infarction increases 4 times, and when three risk factors are together, it increases 10 times.
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