From the clinical point of view, it is not uncommon for "healthy people" who were very active and not morbid to suddenly have acute myocardial infarction. What is the reason? A large number of studies have fully proved that the sudden formation of thrombus on coronary atherosclerotic plaque is the main cause of acute myocardial infarction. So, how is the thrombus in the coronary artery formed? It turns out that people with sudden myocardial infarction actually have small and medium-sized atherosclerotic plaques under the intima of coronary artery. Because it is not big, it has no obvious influence on blood flow and will not cause myocardial ischemia or even myocardial infarction. Therefore, patients can be "healthy" and have no clinical symptoms. However, this kind of small and medium plaque is very dangerous. It belongs to "unstable plaque", also known as "vulnerable plaque". It has a big fat core in the center. Due to the soft texture of the plaque, there is a thin capsule (also known as "fiber cap") on the surface of the lipid core, which is easy to rupture under the impact of blood flow. After the plaque ruptures, it is like cutting a hole in the skin, which will soon form a blood clot, that is, a thrombus. Thrombosis can easily completely block the vascular lumen. If it happens in the coronary artery, it will lead to myocardial infarction due to the interruption of myocardial blood supply. Because the stenosis of vascular lumen was not obvious in the past, collateral circulation has not been formed between coronary arteries. Therefore, once this kind of "healthy people" have acute coronary artery occlusion, they often have no additional channels to provide blood flow, so the area of myocardial necrosis is often large and thorough, the condition is often critical, and the mortality and disability rate are high.
Knowing that coronary plaque is the chief culprit of acute myocardial infarction, then we need to know some common sense of atherosclerotic plaque.
How to judge the existence of large plaque in coronary artery
About the formation of atherosclerotic plaque, this magazine has made many introductions, so I won't repeat them here. Now focus on how individuals can judge whether there is coronary atherosclerotic plaque.
Generally speaking, if there is a large atherosclerotic plaque in the coronary artery, it will often affect blood flow. Most people will have angina pectoris symptoms, that is, when they are nervous, excited or engaged in some kind of labor, they suddenly feel stuffy, bloated, tight, stuffy, heavy or tight behind the sternum, which can be relieved after a little rest. Some people need to take nitroglycerin under the tongue to relieve it quickly.
In other words, people with angina pectoris must have coronary atherosclerotic plaques. This kind of plaque is "old" and has a thick fiber cap, which is called "stable plaque". Although it may rupture and develop into acute myocardial infarction, it is mainly pain, so people are warned that they must see a cardiologist when they feel the above situation.
Small and medium plaques can not be ignored.
Small and medium plaques in coronary arteries are difficult to find, but they can be done with some medical knowledge. It should be pointed out that if middle-aged and elderly people have long-term risk factors for coronary heart disease, especially those who have multiple risk factors at the same time, they must be vigilant. Although they have no symptoms of angina pectoris, they cannot completely rule out the possibility of coronary heart disease, especially small and medium plaques. Intravascular ultrasound examination introduced in recent years is very helpful for this, but this kind of examination is traumatic and expensive, so it is difficult to popularize for the time being.
Risk factors of coronary heart disease
The risk factors of coronary heart disease include hypertension, diabetes, dyslipidemia, smoking, obesity (especially potbellied obesity), less exercise, heavy mental and work stress, less eating of fruits and vegetables, male over 55 years old, female over 65 years old and family history of coronary heart disease. According to research, more than 90% of coronary heart disease is related to these factors.
Two principles and four measures to deal with coronary heart disease
For people who have been diagnosed with coronary heart disease or may have coronary heart disease, two principles are to prevent sudden myocardial infarction and death and reduce angina pectoris. To this end, the following four specific measures should be taken:
1. evaluation: let the doctor evaluate his condition, such as whether he has coronary heart disease, or how likely he is to have coronary heart disease, and whether he needs to do some tests or special treatment.
2. Control risk factors: Under the guidance of doctors, seriously and persistently control the above risk factors, especially quitting smoking, not drinking, proper exercise, low-fat and low-salt diet, mental relaxation, etc. We must control blood pressure, blood lipid, blood sugar and weight at an ideal level.
3. medication: while treating existing diseases such as hypertension, hyperlipidemia, diabetes, etc. You should also take some drugs that help to inhibit atherosclerosis, stabilize atherosclerotic plaques, reduce plaques, resist inflammation and prevent thrombosis, such as angiotensin converting enzyme inhibitor (ACEI), statins, beta blockers, and low-dose aspirin.
4. Prevention: Preventing plaque rupture is the key to prevent sudden myocardial infarction. The research shows that the size of blood flow impact has a great influence on the stability of plaque. ① Excessive fatigue, tension, anxiety, hyperactivity, excessive smoking and drinking can all lead to unstable blood pressure and corresponding changes in myocardial contractility. When the impact of blood flow on plaque increases, it may lead to plaque damage and rupture. ② The increase of some substances in the blood can also cause the damage of plaque fibrous cap, such as the excessive release of angiotensin Ⅱ and catecholamine during mental stress, hyperglycemia during diabetes, the increase of some blood lipid components during dyslipidemia, inflammation and inflammatory substances during infection, etc. Therefore, it is very important to take corresponding measures against these unfavorable factors.
Clinical observation shows that a small number of myocardial infarction is not caused by blood vessel blockage, but by severe spasm of coronary artery, which leads to severe stenosis, occlusion and blood flow interruption. However, most of these spasmodic vessels have a certain degree of atherosclerosis, and a few have no obvious lesions. Therefore, in this case, the above preventive measures are also beneficial and important. In addition, there are very few patients whose myocardial infarction is caused by other diseases, such as thromboembolism, arterial inflammation and dissecting aneurysm. In order to prevent myocardial infarction, it is also necessary to correctly diagnose and actively treat these related diseases.
If we understand this, we should eliminate all kinds of risk factors leading to coronary heart disease and attach great importance to the dangerous signals sent by the body. I believe that most acute myocardial infarction can be prevented.