撰写Original card shark talk with card shark
Hello, heart!
-card shark
be clear in mind (about sth)
If we have to choose a "model worker" from the human body, I think it must be the heart. In this regard, a little understanding of some data about the heart, we will know that the model of the heart really does not rely on "words", and those "off the charts" values that represent the length of life are all the accumulation of the heart from jump to jump and from minute to minute.
The heart of an adult is about 15 cm long and weighs 350 grams. The size of a human heart is about the size of two hands clasped together. A normal heart has four chambers (left and right atria and left and right ventricles) and four sets of valves (aortic valve, pulmonary valve, mitral valve and tricuspid valve). A healthy heart valve is equivalent to the size of half a coin. The heartbeat you hear is the sound made by the collision when the heart valve is opened and closed. Valve-related heart diseases are mostly structural heart diseases.
Although the heart is only the size of an ordinary pear, in its life, the heart has been silently pumping blood for a body weighing 200 times its weight, sending fresh oxygen and nutrition to the body and taking away harmful waste.
The heart has never stopped since it was on duty independently. When it stops, people stop.
As the most industrious organ in the body, the heart beats about 100,000 times a day, 40 million times a year, and 3 billion times in its life. It is responsible for pumping about 8,000 liters of life-sustaining blood into a blood vessel network of 6,000 miles (about 96,000 kilometers, two and a half times around the equator of the earth) every day. Some people have done calculations, and the work that the heart does by pumping blood in a lifetime is about equivalent to lifting 30,000 kilograms of heavy objects to the summit of the Himalayas.
The heart is the strongest pump in the body. It stopped pumping, so people stopped jumping.
The heart also has time to go to work and rest every day.
When in normal working condition, the heart beats about 70 times per minute for about 0.9 seconds each time, of which, it contracts in 0.3 seconds, that is, it works; 0.6 seconds relaxation, that is, "rest". In other words, the heart spends 1/3 of its time working and 2/3 of its time resting during the day. When people are asleep, the heart automatically adjusts the number of beats per minute, with a working time of about 1/4 and a rest time of about 3/4.
Mother and child are connected to each other
Mother and child are linked to each other, and they are sincere.
The heart is a complex organ. Understanding the development of fetal heart can help us understand congenital heart disease and know how to prevent it.
The heart begins to form in 3-4 weeks of embryo. Theoretically, there will be an initial fetal heart at this time. Now, the initial fetal heart can be monitored in the fifth week of embryo development, and the fetal heart beat can be monitored in the sixth week. This is already the fetal heart beat. In the mother’s womb, the development of fetal heart goes through several different stages. At first, it looks like a fish’s heart, and then it looks like a frog. In this period, the fetal heart has only two chambers. Later, it developed into a snake-like heart with three chambers; Finally, it forms the heart of human’s four-chamber structure.
Clinically, monitoring fetal heart beat is helpful to remove vacuoles, and can also be used to check the development of fetal heart at 4-5 months, and to check some congenital heart diseases.
The role of fetal heart in fetal development is negligible, so where does the oxygen and nutrients needed for fetal physical development come from? They are all obtained from the mother by umbilical cord (the material basis of mother-child connection).
What deserves our attention is that during the period of fetal heart formation, it just happens to cross with the teratogenic sensitive period for a long time. The teratogenic sensitive period starts from the 18th to 20th day after conception, and the peak is about the 30th day, and the sensitivity decreases rapidly after the 55th to 60th day. This period is from two and a half weeks to about nine weeks.
The key period of heart development is from the second weekend to the third week, when the fetus is highly sensitive to harmful substances from the outside world, which lasts until the sixth week or so. If the mother still maintains bad living habits during this period, it may affect the development of fetal heart, leading to imperfect heart development and defects-congenital heart disease will occur. Congenital heart disease will affect the survival rate of babies and the quality of life during their growth after birth.
Therefore, to repeat, fetal heart rate can be used to identify some congenital diseases in children, which is one reason why mothers must do fetal heart rate monitoring for several months of pregnancy.
When the fetus is 4-5 months old, the heart is basically fully developed, which is the earliest period for premature infants with the shortest development time to survive. Note that what I said is that the heart is basically fully developed. Speaking of it, the development of the heart will continue even after birth.
The independent work of the heart begins after birth and leaving the mother.
Yixin lianglu
The heart has its own two sets of relatively independent and closely coordinated systems: one is the "circuit"; One set is "oil circuit".
The heart works completely autonomously thanks to the "circuit" system. The frequency of heart beating is determined by the brain according to the running condition of the body, and its speed is controlled by nerve conduction. This is the heart "circuit" system that we often say for example.
The electrical excitement and impulse conduction of the heart are going on all the time.
The excitement of normal heart normally originates from sinoatrial node, and then passes through atrial muscle or dominant conduction system in atrium to atrioventricular node. In this part of the atrioventricular node, especially in the node area, the excitement will slow down, which is called atrioventricular delay. The excitement will be transmitted from the atrioventricular node to the atrioventricular bundle, where it will be divided into two branches and transmitted to the lower part of the ventricle, which is called the left and right bundle branches. These two bundle branches will contract together, so that the ventricles on both sides will contract synchronously, and then be transmitted from the left and right bundle branches to Purkinje’s fibrous network to complete the conduction of cardiac excitement.
There is something wrong with the "circuit" of the heart, whether it is "short circuit" (fast) or "power failure" (slow), we call it "arrhythmia".
Excitement of the heart can cause contraction and relaxation of the heart, about 70 times per minute, and each heartbeat fills its four chambers with a new round of blood.
The "oil circuit" system of the heart refers to the blood circulation of the heart itself, which is the source of energy and power for it to work as a pump. Here, the coronary heart disease we mentioned below means that there is a problem with the coronary artery.
Coronary arteries are divided into left and right coronary arteries and their branches. Coronary artery is the first pair of branches of aorta. Its perfusion pressure is relatively high, blood flow velocity is relatively fast and circulation path is relatively short, so the blood supply of coronary artery is quite sufficient. They transport blood to nourish myocardial cells, and the blood flows through capillaries and veins and then returns to the right atrium. The normal operation of coronary circulation ensures that the heart can continuously perform the function of "pump".
Coronary artery problems, such as coronary heart disease, such as myocardial infarction, may affect the systolic and diastolic function of the heart. This pump will no longer work properly.
Be preoccupied
We are used to the "model worker" of the heart. We thought it was an invulnerable and indestructible weapon.
Don’t you know that its "atrioventricular structure" and its "water circuit" system will also "age"; It will also be invaded by inflammation, immune damage, degeneration and even tumors (mainly metastases).
Don’t you know that cardiovascular disease is still the most important cause of death in the world today with many new technologies and drugs for treating heart disease? Unless more active actions are taken, it may kill 20 million people every year by 2025, and about 80% of them will die in low-and middle-income countries.
Therefore, the heart needs everyone’s care.
One reality that everyone must understand is that the turning point of death of coronary heart disease in the United States began to appear in 1968; Half a century later, the death rate of coronary heart disease is still rising in China. Coronary heart disease myocardial infarction still presents a trend of early onset and high incidence!
It is a fact that we must be clear that the background of the decline of coronary heart disease death in the United States in the last century is that there are neither lipid-regulating drugs such as statins nor modern reperfusion treatments: thrombolysis and coronary intervention.
One problem that everyone must understand is that the decline of mortality rate of coronary heart disease must be combined with prevention and treatment in the end. Without prevention, there is no heart health in the sense of group.
Therefore, heart health needs everyone’s attention and efforts.
At this point, I think most people should say hello to our "model worker" heart:
Hello, heart.
– End –
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