Heart/ Circulatory

Cardiovascular diseases still belong to the most frequent causes of death in the world. In the western industrial countries, the amount of death due to cardiovascular diseases is approximately 45%. In developing countries the percentage is 25%; this is significantly less than in industrial countries. Cardiovascular diseases are disorders which affect the heart as well as the vasculars surrounding it. Disorders which can be taken into account of cardiovascular diseases are angina pectoris, arterial hypertonia, apoplexy, diabetes mellitus, hypocholesterinaemia, cardiac dysrhytmia . All of these disorders as well as raised blood fat values in general can lead to the pathological disorder of atherosclerosis (or 'arteriosclerosis'), which is a diseased change of the vascular wall. Through damage on the vascular walls, which can occur through various mechanisms, a deposit of fat- and protein complex develops which is called 'arteriosclerosis'. During the following process, these complexes relocate below the inner vascular wall and, thus, lead to swelling. Hence, the vasculars lose their elasticity and become stiff and inelastic. This means that the vasculars cannot be passed by the necessary amount of blood any more since the calibre of the vascular decreases. Consequently, any target location like an organ like, for example, the kidney or extremities like legs and arms, are not supplied adequately.

The insidious beginning of arteriosclerosis makes it a very treacherous disease. The pathological disorder of the cardiovascular is a disorder which mostly occurs on older people. However, there now is evidence for that the number of people suffering from this disorder is increasing. This concerns people under 50 years. Today, for example, more and more children suffer from obesity. Therefore, a diseased change of the vasculars can be detected on them. Risk factors for cardiovascular diseases are smoking, stress, psychological bearings, not enough exercises and unhealthy nourishment. The fact that unhealthy nourishment is increasing can especially be observed in today's industrial countries.

Apart from the characteristic risk factors, modern studies suggest that genetic disposition also plays an important role when it comes to a higher risk of getting any cardiovascular disease. Thus, new findings support even more identified risk factors like, for instance, an encouragement of atherosclerosis through an increased blood level of a certain amino acid which is called 'homocystein'. Hereby, the mutation of one single base of the nucleotide sequence of the methylenetetrahydrofolate reductase (MTHFR) gene leads to an increasing homocystein level of the blood. Homocystein can cause a direct effect, which is toxic, within the vascular wall concerned and, thus, can lead to thrombosis. Patients who have mutations in the coagulation factor genes, like, for example, in factor II and factor V, are also in great danger of getting thrombosis. Further genetic factors which support the development of atherosclerosis are gene mutations in certain transport protein components, the apolipoproteins, which are responsible for the removal of cholesterol. Cholesterol gets through particular transporters like the Low density lipoprotein 'LDL' in the body. The different cell receptors then store the complex. The apolipoprotein B-100 (ApoB-100) is the main component of the 'Very Low Density lipoprotein' (VLDL), ''Intermediate Density lipoprotein''(IDL) and LDL. Due to the interaction of ApoB with the LDL receptors, ApoB-100 makes the transport of the LDL- cholesterols into the liver and in most other cells of the body possible. One single mutation of position 3500 of the ApoB-100 lipoprotein leads to a decreased ability of the receptor’s bonding and, thus, to a worse LDL- Clearance through the liver. The consequence is an increment of the plasma-cholesterol-level and of the LDL-level. This means the risk of a cardiovascular disease increases.

A further significant risk factor for suffering a cardiovascular disease is high blood pressure ('arterial hypertonia'). Characteristic for high blood pressure is that it is more frequent with older people. The angiotensin converting enzyme(ACE) plays an important role in the regulation of high blood pressure and in the balance of electrolytes in that ACE transforms angiotensin I into angiotensin II. Angiotensin II is a potent vasopressor and participates in the cardiovascular homoeostasis. The human ACE gene has an insertion (I)/ deletion (D) polymorphism. The D/D polymorphisms is associated with a high ACE plasma level which leads to an increased angiotensin II concentration. This is associated with an increased disposition of hypertonia (high blood pressure), which is a another risk factor for heart attacks or strokes.

Recommended Tests:
APOE
APOB
MTHFR
Faktor II
Faktor V
ACE
PAI-1
PPARG
FABP
ADRB2

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