Diseases of the coronary arteries | Coronary arteries – anatomy and diseases

Diseases of the coronary arteries

A major cause of coronary artery disease is coronary artery disease (CHD), which leads to an insufficient oxygen supply to the heart muscle tissue. Under physical exertion the oxygen demand of the heart muscle increases. In a healthy person, the coronary arteries would dilate so that more oxygen-rich arterial blood could supply the heart muscles.

In patients with CHD, however, this is usually not possible, so that the ability to cope with stress is greatly reduced. Finally, if the entire coronary artery is blocked, this leads to the death of the heart muscle tissue to be supplied, which is only reversible to a certain extent and for a certain period of time. The performance of the heart muscle can drop sharply under such conditions.

Behind a CHD is usually arteriosclerosis, which leads to stiffening of the coronary arteries and can sooner or later also end in vascular occlusion. Depending on how quickly an occlusion develops, the consequences can be of varying severity. In addition to CHD, spasm of the coronary arteries can also lead to symptoms, but these are reversible.

Arteriosclerosis is a disease of the arteries, in the case of the coronary arteries, which occurs primarily in the inner layer of the blood vessel, the so-called “intima”. Usually the cause is an injury to this layer, which is called an “endothelial lesion”.This triggers a colonization of platelets at the injured site, which in turn leads to the emission of certain substances that promote the attachment and penetration of further cells at this site of the intima. In the course of time, the structure changes into a plaque, which is less elastic and rather hard due to the connective tissue reconstruction.

This has enormous effects on the coronary arteries, as the entire blood vessel loses elasticity and the risk of a heart attack increases. Arteriosclerosis is mainly promoted by an unhealthy lifestyle, i.e. high blood lipid levels, smoking, lack of exercise and high blood pressure. If the mentioned risk factors of a Arteriosklerose are determined, then one can contain their extent for example by a conversion of the nutrition, by sport or by certain medicines and reduce so the Arteriosklerose risk.

Symptoms that are due to coronary artery disease manifest themselves in various ways. Some of them are rather unspecific, which means that they cannot always be automatically associated with the coronary arteries. In some cases, the symptoms manifest themselves during reduced physical activity in sports or even in everyday life, or even at rest.

Others react with symptoms only in stressful situations. Relatively unspecific symptoms are indisposition with nausea or water retention in the legs (edema). A typical symptom, on the other hand, is a feeling of tightness in the chest, known as angina pectoris.

It sometimes occurs with pulling, burning and stabbing pain. The pain often radiates into the left arm, alternatively into the neck, jaw or back. In these cases, it is best to consult a doctor as soon as possible in order to make further diagnoses or to provide help.

In the worst case, damage to the coronary arteries can result in a heart attack with or without fatal consequences. If typical symptoms of coronary artery disease occur, an ECG is first written for the diagnosis. This is initially performed at rest, and for further clarification also under stress.

If the coronary arteries are suspected to be impaired, depending on the urgency of the case, echocardiography, magnetic resonance imaging, spiral computed tomography or coronary angiography with a contrast medium is performed, which could also be used to quickly initiate therapy. Here, the patency of the coronary arteries and the blood flow and vitality of the heart muscle are assessed. In addition to ECG and imaging, certain blood values, such as troponin or creatine kinase of the heart muscle, can provide information about the state of health.

The therapy consists on the one hand of reducing the risk factors. The focus is on adjusting blood pressure values and reducing blood lipids. In addition, the patient should be informed about the benefits of physical activity and the harmfulness of smoking.

In the event of acute tightness in the chest, drugs such as a nitro preparation can be given to make the coronary arteries dilate in a short time. If coronary artery disease is already advanced, depending on the extent of the occlusion a stent or a bypass can be considered to ensure reliable blood supply to the heart. A stent is the English technical term for “vascular support” and is usually a wire mesh used to keep a blood vessel open.

It is folded up on a catheter and brought to the affected coronary artery either via the inguinal artery or the artery of the wrist. It is then pressed against the wall of the blood vessel with the help of a balloon to open the vessel again and ensure the blood supply to the heart. In order to know which coronary artery is affected and where to place the stent, coronary angiography is used, which uses a contrast medium to provide an accurate image of the coronary arteries.

Since the platelets of the blood clotting process like to lie on the surface of the stent and form a blood clot, it is important to start with dual platelet aggregation inhibition before the procedure and to continue with it after the stent has been placed, so that the stent remains open as long as possible. Suitable drugs are acetylsalicylic acid in combination with, for example, clopidogrel. There are also coated stents that are not supposed to allow platelets to attach.

The stent is mainly used for fresh heart attacks or coronary arteries that are about to close and has a comparatively high chance of success.In addition, the patient is not stressed so much during this procedure, since only a puncture of one of the arteries is performed and no general anesthesia is required. Possible side effects include rapid stent resealing, the dissolution of a blood clot or the placement of an outgoing artery through the stent. However, this is a rare occurrence.

The prognosis of CHD is difficult to assess, since both genetic and environmental factors play a major role in its development. Especially in industrialized countries, CHD still frequently leads to death. Although risk factors can be controlled by a healthy lifestyle and medication if they are diagnosed early enough, damage to the coronary arteries often manifests itself at a late stage.

It is therefore important to prevent coronary artery disease at an early stage through exercise, a healthy diet and regular health checks by a doctor. In order to prevent coronary artery disease, a healthy lifestyle should be followed, including a balanced diet and sufficient physical activity. Smoking should also be stopped immediately. If the disease is already present, regular medical check-ups and taking the prescribed medication as prescribed are important.