Atherosclerosis is a chronic degenerative disease of the arteries characterised by a thickening of vascular wall and loss of elasticity. The most frequent type of atherosclerosis is the atheroma type characterised by the formation of plaques inside the walls of arteries. The consequences of advanced atherosclerosis are e.g. stroke, myocardial infarction and ischaemia of the extremities.
Symptoms
The symptoms of atherosclerosis appear only in the advanced stages of the disease, when the artery is so damaged that critical constriction (stenosis) or even occlusion of its lumen occurs. Typical symptoms include sudden pain in the area of the organ with reduced blood flow. In the case of mere constriction and insufficient blood flow, these symptoms appear on exertion and recede at rest. If complete occlusion occurs, there is a great risk that the area of the organ lacking any blood flow will necrotise and that is function will thus be severely impaired. Symptoms thus vary considerably according to which organ is involved, to what extent and how rapidly blood flow is restricted.
The most frequent cases are:
Arteries of the brain
This may involve loss of consciousness, partial or complete paralysis of the extremities on one side of the body, loss of sensitivity, damage to facial mimicry etc. The extent of the damage varies. These changes may be short-term or permanent. Milder manifestations may be in the form of a so-called transitory ischaemic attack (TIA), which manifests as only short-term symptoms (unconsciousness of short duration, disorders of mobility, speech, sensitivity that recede within 24 hours).
Arteries of the heart
A plethora of symptoms from angina pectoris (intermittent chest pain, most frequently on exertion due to insufficient blood flow through the heart muscle that recedes at rest after a while) to complete myocardial infarction (occlusion of a coronary artery associated with chest pain). This is a life-threatening situation for the patient. During a myocardial infarction, patients feel a compressive, constricting or burning chest pain, which is more intense and lasts longer than a common attack of angina pectoris. This pain may irradiate into the hand, shoulder, lower jaw, diaphragm and back. A myocardial infarction is often associated with dyspnoea, anxiety and sometimes vomiting. It may occur suddenly, with no previous warning. A completely painless myocardial infarction, so-called silent infarction, is sometimes observed in diabetics and older patients.
Arteries of the lower extremities
In ischaemic (arterial) disease of the lower extremities, patients most frequently complain of claudication pain- pain in the legs on exertion that forces the patient to stop and interrupt his walk. Later, pain appears at rest, the extremity is cold; there is hair loss and often fungal infections. Long-term insufficient blood flow leads to the development of skin defects that take long to heal. In the case of complete occlusion, the lower extremity is threatened with so-called gangrene- tissue necrosis and subsequent infection that often requires partial amputation of the extremity.
Causes
Atherosclerosis is the consequence of the deposition of fat, calcium and other substances in the arterial wall. Apart from unsuitable lifestyle, this process is also contolled genetically. This relates to changes in the concentration of fatty particles in the blood (increased total cholesterol and “bad” LDL cholesterol levels, low “good” HDL cholesterol levels and high triacylglycerols). When the internal lining of the arterial wall is damaged, e.g. due to smoking, high blood pressure, fatty particles-lipoproteins- penetrate into the arterial wall and cholesterol crystallises there. This gives rise to the atherosclerotic plaque. Overall, there is a thickening of the arterial wall, a decrease in its elasticity, and narrowing of its lumen with consequent limited blood flow. The organs are then insufficiently supplied with oxygen, which often (but not always) manifests as pain, and subsequently these organs are damaged and may fail. The cause of this disease is not completely clear. Several factors associated with an increased risk of atherosclerosis are known:
Treatment
The treatment of atherosclerosis has many forms.
Prevention
This consists of restricting the aforementioned risk factors (especially high blood pressure, smoking, increased level of fats in blood, obesity and stress). It is advisable to determine the amount of fats in blood, and if pathological values are found, to attempt to decrease cholesterol levels (especially so-called LDL = “bad” cholesterol) as well as those of the other type of fat- triacylglycerols. We have highly efficient drugs at our disposal that can help us, along with dietary measures. It is necessary to decrease the intake of animal fats (rich in cholesterol and unsaturated fat) and include in one’s diet more fruits and vegetables. If we are overweight, we gradually decrease our weight; limit our intake of sugars (beware of hidden sugars in soft drinks!) Regular aerobic activity is important. We choose the type of exercise that best suits us. For the exercise to be effective, we consult a physician or instructor.
What does GenScan reveal about atherosclerosis?
GenScan analyses those genes that participate in the development of atherosclerosis. We mainly focus on genes that participate in lipid (fat) metabolism, especially that of cholesterol, as well as genes that regulate arterial lumen size. On the basis of GenScan analysis, the physician may recommend targeted preventive measures, including pharmacological intervention.