Keywords: coronary heart disease
The causes of coronary heart disease is the corresponding coronary branches atherosclerosis or arterial spasm:
1. Coronary atherosclerosis: coronary artery disease is the most common narrow, especially muscle wall outside the coronary artery branch of atherosclerosis. Coronary artery proximal segment is the reason atherosclerosis predilection than all organs artery close to the ventricle, and thus exposed to the maximum impact of systolic blood pressure. Furthermore, the coronary artery tree because of the shape of the heart, the majority of change in direction, and therefore also bear a greater blood flow shear stress.
Predilection sites: According to the autopsy statistics in our country, the total detection rate of lesions, narrow detection rate and the average level before descending branch of the highest, followed by the right trunk, the left main coronary artery or the left circumflex artery, posterior descending branch.
Gender differences: 20 to 50 years old lesion detection rate of males was significantly higher than the female; no significant difference between men and women after the age of 60.
The lesion characteristics: the distribution of atherosclerotic plaque in the proximal segment and heavier at the branch mouth; early plaque dispersed, showed segmental distribution, as the disease progresses, the plaque adjacent integration . In the transverse section plaque Duocheng crescent, the lumen showed varying degrees of stenosis. Sometimes be complicated by thrombosis, so that the lumen completely blocked. According to the plaque causing Ⅳ degree of stenosis can be divided into four: Ⅰ grade stenosis in 25%; Ⅱ grade stenosis in 26% ~ 50% of; Ⅲ grade, narrow 51% ~ 75% of; grade stenosis in 76% or more.
2. Coronary artery spasm: academia coronary spasm cause of ischemic heart disease, “the issue has been controversial. Some research Mind sudden death cases found that the incidence of coronary thrombosis rate was only 30%, only 50% of patients died within 12 hours after the onset of, so that at least a considerable part of the cases are caused by coronary artery spasm ‘s. In recent years, through examination of the cardiovascular imaging technology has proven coronary artery spasm can cause angina and myocardial infarction.