The gradual calcification of the coronary arteries with all its consequences is the most common heart disease of all in the western industrialized nations – in Germany, almost one third of all men and 15 percent of women are affected. For years, it has been the leading cause of death. Coronary heart disease is caused by chronic deposits of fatty substances, salts and small blood clots circulating in the bloodstream on the walls of the coronary vessels. These increasingly constrict the vessels, thereby impairing blood circulation.
Atherosclerosis as a sign of general vascular disease
The deposition processes in the veins, also called arteriosclerosis, also occur in the blood vessels of other organs, such as the kidneys, brain, or lower extremities, depending on individual susceptibility and the presence of appropriate risk factors. Thus, coronary artery disease is only a specific expression of a general vascular condition, which in this case takes place in the blood vessels of the heart muscle.
How coronary artery disease develops
The exact causes of coronary heart disease are not yet clearly understood scientifically and often cannot be precisely determined in individual cases. However, a number of risk factors for cardiovascular disease are known to be present, and if they are present, there is a significantly increased likelihood compared with the normal population that coronary heart disease will occur during a person’s lifetime.
If several of these risk factors are present in a patient, the risk of being affected by coronary heart disease is correspondingly potentiated:
- Obesity
- Diabetes
- Lipid metabolism disorder
- Hypertension
- Gout
- Older age
- Male gender
- Smoking
- Cardiovascular disease in first-degree relatives.
A not insignificant role in the development of coronary heart disease plays the genetic predisposition. Thus, it is quite possible that coronary heart disease occurs despite an absolutely healthy diet and lifestyle and no objectively detectable risk factors or, conversely, a person reaches a ripe old age despite an unhealthy lifestyle and risk factors.
Characteristics of coronary heart disease
Progressive atherosclerosis leads to a deficient supply of blood to the heart muscle: Insufficient blood reaches the heart muscle through the fatty, calcified, thickened coronary arteries. Initially, this is usually the case only under stress conditions, i.e. when the muscle needs more oxygen to do its work, but later it also occurs at rest.
Coronary heart disease accordingly manifests itself through its effects in the form of various clinical pictures, which can also occur together. Typical clinical pictures of coronary heart disease include angina pectoris and myocardial infarction, as well as their consequences.
Disease pattern angina pectoris (heart stenosis).
As the coronary arteries become increasingly narrowed, their blood-carrying capacity also becomes more and more limited, which can lead to a mismatch between oxygen demand and supply at the heart muscle. Only when the constrictions exceed a critical level do symptoms such as pain radiating from the chest, shortness of breath and an oppressive feeling of tightness in the chest appear.
If the disease progresses slowly, these symptoms manifest themselves in the early stages as angina pectoris on physical exertion. As the disease progresses and higher-grade narrowing of the coronary arteries occurs, exertional angina can become resting angina – a threatening alarm symptom that can seamlessly transition to a heart attack.
Clinical picture of myocardial infarction
The sudden occlusion of a coronary vessel that was previously still flowing with blood (for example, due to a clot that grafts onto the calcifications and completely closes the already narrowed vessel) leads to the death of a part of the heart muscle of varying size.
In the best case, this district is subsequently replaced by a connective tissue scar, which remains as a defect of the heart muscle for the rest of life and usually also means a restriction of the contractile force of the heart muscle – heart failure (cardiac insufficiency) or chronic cardiac arrhythmias. In the worst cases, acute complications such as ventricular arrhythmias and sudden heart failure lead to death.