ATHEROSCLEROSIS

Atherosclerosis is a common chronic disease characterized by lipid infiltration of the inner aortic membrane, large and medium-sized arteries, and the growth of connective tissue in their walls. With arteriosclerosis, the arterial lumen narrows, the density of the arterial wall increases, and its extensibility decreases; In some cases an aneurysmal stretching of the artery walls is observed.

One of the main factors in the development of atherosclerosis is hyper- and dyslipoproteinemia - a disproportion in the content of various classes of lipoproteins in the blood plasma, some of which contribute to the transfer of cholesterol to the vascular wall, ie, are atherogenic, others hinder this process. The most common types of hyperlipidemia are IIa according to Frederickson (cholesterol level exceeds 5.2 mmol / l, triglyceride level is normal), IIb (cholesterol level above 5.2 mmol / l, triglycerides - above 1.6 mmol / l), type IV (Cholesterol level within the norm, triglycerides - above 1.6 mmol / l). Persistent atherogenic hyper and dyslipoproteinemia, as a rule, are family-hereditary. The occurrence of such disorders and the development of the disease is probably facilitated by the prolonged use of food containing an excess of animal fat, rich in cholesterol.

In addition to hyper- and dyslipoproteinemia, arterial hypertension , obesity , insufficient physical activity and smoking are of great importance in the onset of atherosclerosis.

The earliest manifestations of atherosclerosis are lipid spots, or lipid bands - flat spots of a yellowish color, of various sizes, located under the inner aortic membrane, most often in its thoracic region. Yellowish color stains attached to them cholesterol. Over time, some lipid spots dissolve, while others, on the contrary, grow, occupying an increasing area. Gradually, the flat spot turns into a cholesterol plaque protruding into the lumen of the artery (sclerosis of the artery develops). In the future, the plaque thickens, germinating with a connective tissue, often in it calcium salts (calcification of arteries) are deposited. A growing plaque narrows the lumen of the artery (stenosis of the artery), and sometimes completely clogs it. Vessels supplying the plaque with blood and lying in its base are traumatized with a plaque and can be torn to form a hemorrhage that raises the plaque, exacerbating the narrowing of the artery lumen until complete closure. Insufficient blood supply of the plaque often leads to the fact that this content is partially necrotic, forming a messy detritus. Such plaques can be plural; In these cases they speak of atheromatosis. Because of insufficient blood supply, the surface of the fibrous plaque is sometimes ulcerated, while the endothelial covering the plaque is sloughed. Blood platelets that do not adhere to the intact vascular wall settle in an area devoid of the endothelium, giving rise to thrombus development and increasing stenosis of the artery. The defeat of the middle wall of the artery wall reduces its elasticity and strength, which can be the cause of the development of an aneurysm.

Clinical manifestations of atherosclerosis depend on preferential localization. With atherosclerotic narrowing of the coronary arteries, ischemic heart disease develops, manifested by angina pectoris, myocardial infarction, various conduction abnormalities and cardiac arrhythmias. Prolonged repeated myocardial ischemia, and especially repeated heart attacks lead to replacement of the heart muscle tissue with connective tissue scars - cardiosclerosis. If the total mass of dead and connective tissue-substituted heart muscle cells is large enough, cardiac output decreases, heart failure develops .

A widespread and significantly pronounced atherosclerosis and atheroma atheroma can be the cause of the formation of its aneurysm (see Aortic Aneurysm ), which is manifested by the symptoms of compression of the organs adjacent to the aorta. The most dangerous complications of the aortic aneurysm are its delamination and rupture.

Atherosclerosis of the cerebral arteries and extracranial arteries feeding the brain (carotids, vertebrates) is manifested by memory loss, especially about recent events, dizziness, personality changes (usually those pathological features that predominate before the development of atherosclerosis become pathologically aggravated: the lean person becomes a miser, emotionally Vulnerable - weak-hearted, etc.), sometimes periods of obscuration of consciousness. Severe atherosclerosis of the cerebral arteries predisposes to the onset of stroke, especially in patients with high arterial hypertension.

In severe arteriosclerosis of the arteries of the abdominal cavity abdominal pain is often observed - the abdominal toad. A terrible complication of atherosclerosis of the mesenteric arteries is thrombosis with necrosis of the intestine. The thrombosis of these arteries is manifested by severe pain in the abdomen and obstruction of the intestine.

Atherosclerotic stenosis or thrombosis of the renal arteries is manifested by high and often refractory renal disease, or vasorenal, arterial hypertension.

Often when arteriosclerosis affects the arteries of the lower extremities. Obliteration or occlusion develops at the site of separation (bifurcation) of the abdominal aorta into the iliac arteries (Lerish syndrome), femoral arteries and arteries of a smaller caliber are more rarely affected.

Acute occlusion is manifested by severe pain in one or both legs, blanching and cooling, and marbling of the skin. With slowly growing obliteration, when collateral develops around the affected arteries, there is a so-called intermittent claudication - leg pain that occurs when walking and stops almost immediately after stopping.

In the early stages of the disease (before the appearance of fibrotic changes), the reverse development of cholesterol plaques in the arteries is possible, while observing a diet with a minimum content of animal fat and simple carbohydrates (sugar, sweets) from which lipids are synthesized in the body. Recommend a diet containing vegetable fats, rich in polyunsaturated fatty acids - corn, linseed oil, a number of varieties of margarine. If dyslipoproteinemia persists in the foyer of diet compliance, drug therapy is indicated. Usually used as a monotherapy nicotinic acid, which lowers the level of cholesterol and triglycerides in the blood; Statins - lovastatin (livakor), simvastin (zakar), pravastatin (lipostat) - reducing the synthesis of cholesterol in the liver and effective types IIa and IIb of hyperlipidemia; Fenofibrate, which reduces the level of triglycerides in the blood and is effective in type IV hyperlipidemia. Drug therapy is prescribed by a doctor, is carried out for a long time (sometimes years) and requires periodic monitoring of biochemical blood parameters. Adequate correction of violations of lipid metabolism slows the development of atherosclerosis and reduces mortality among patients from cardiovascular diseases.

Surgical treatment is carried out in a hospital. It is used for significant stenoses, blockage or aneurysm of large arteries. If the arteries stenosing the artery is located near the mouth of the vessel, sometimes only the plaque is removed (endarteriectomy). With stenotic atherosclerosis, stretching of the narrowed portion of the vessel is found using a special canister located at the end of the vascular hollow catheter: intravascular balloon dilatation or percutaneous (intravascular artery through a needle) intravascular angioplasty. At the expressed obliterating atherosclerosis of arteries of different regions, operations of shunting blood vessels are used, ie creation of blood flow around the affected area of ​​the vessel with the help of the patient's own vein (autotransplantation), another blood vessel (homotransplantation) or artificial prosthesis (heterotransplantation). With aortic aneurysm, prosthetics of the affected area are performed.

The prognosis depends on the localization, severity and prevalence of atherosclerotic lesions of the arteries. In a number of cases, manifestations of atherosclerosis develop extremely slowly, for several years or even decades (for example, angina often occurs after the age of 60 years, and for several years seizures are observed only with considerable physical exertion). In such cases, the outlook is relatively favorable. In severe manifestations of atherosclerosis (primarily in coronary heart disease) developing at a young age in patients with familial-hereditary hyper- or dyslipoproteinemia, the prognosis is unfavorable both in terms of working capacity and in relation to life. Adverse effects on the prognosis of concomitant hypertension , diabetes .

Prevention. The basis for the prevention of atherosclerosis is a rational way of life: the mode of work and rest, which reduces the likelihood of mental overstrain; Elimination of hypodynamia, physical fitness training; Refusal to smoke and drink alcohol; Proper nutrition; Ensuring the stability of normal body weight. Important in the prevention of atherosclerosis is the timely detection of hypertension, as well as diabetes, predisposing to the development of vascular lesions, and their systematic carefully controlled treatment.