The full name of coronary heart disease is coronary atherosclerotic heart disease, which is caused by myocardial ischemia and hypoxia due to coronary artery atherosclerosis. It is often clinically manifested as precordial pain, chest tightness and other symptoms. The pathogenesis of coronary heart disease is mainly related to the following points:
1. Pathologically, the degree of vascular stenosis is evaluated by measuring the cross-sectional stenosis area of the most severe stenosis site. Generally, only those with a stenosis area greater than 50% will cause a significant reduction in coronary artery blood flow, which is directly related to the occurrence of coronary heart disease.
2. Stability of atherosclerotic plaques When atherosclerosis occurs in arteries, there is a large amount of calcium deposits in the elderly and severe plaques, and these calcified plaques are usually relatively stable. However, some plaques without calcification, or when the plaque develops into a thick calcified cap and increases the stress between the adjacent endometrium, are prone to rupture and thrombosis, leading to unstable angina, myocardial infarction, and even sudden death.
3. Coronary spasm refers to the transient constriction of the coronary arteries, causing partial or even complete occlusion of the blood vessels, and is an important factor in the development of coronary heart disease. The main factors that cause coronary artery spasm are as follows:
Neurological factors: Coronary arteries have abundant alpha receptors. When under psychological stress, cold stimulation, or intense exercise, excessive excitation of the sympathetic nervous system can induce coronary artery spasm.
Fluid factors: ① The balance between prostacyclin and thromboxane directly affects the systolic and diastolic state of coronary arteries. When prostacyclin decreases and/or thromboxane increases, it can lead to coronary artery spasm. ② The balance between endothelin and endothelial derived relaxing factor also affects the occurrence of coronary spasm. ③ When serum calcium ions increase and hydrogen ions decrease, more calcium ions enter the cell, thereby increasing coronary tension and inducing coronary spasm; Magnesium deficiency can cause coronary artery constriction.
Summary: The pathogenesis of coronary heart disease is complex, but regardless of the cause, active prevention is the most important. According to statistics, 80% of sudden cardiac death is caused by coronary heart disease, and many patients even have no symptoms before onset. Therefore, it is recommended that middle-aged and elderly people undergo regular heart check ups to prevent problems before they occur.