1. What are the structural characteristics of the heart? Why is the heart compared to a pump?
A: The heart is divided into the left heart and the right heart on both sides, and the left and right hearts are each divided into the left atrium, left ventricle and right atrium and right ventricle for a total of four heart chambers. The role of the heart is similar to that of a pump, which pumps blood from the veins into the right side of the heart (from the right atrium into the right ventricle) around the clock, and then pumps blood into the lungs, where it receives oxygen and flows into the left side of the heart, and then shoots into the arterial vessels through the left atrium to the left ventricle, and transports blood to all parts of the body through the aorta and its systemic arterial branches, providing oxygen and nutrients to all living cells of the body.
2.What valves are there in the heart?
A: The valve between the right atrium and the right ventricle is composed of three valves, called the “tricuspid valve”. The valve between the left atrium and the left ventricle is composed of two valves, so people call it “mitral valve”. Between the right ventricle and the pulmonary artery, there is a valve consisting of three semilunar valves, which is called the “pulmonary valve”. When the blood absorbs enough oxygen and expels carbon dioxide in the lungs, it flows into the left atrium, goes to the left ventricle, and then is discharged from the other exit of the left ventricle (aortic valve), and the valve between the aorta and the left ventricle is called the “aortic valve”.
3.What are the components of the heart wall? Is the heart wall the same thing as the heart muscle?
A: The heart wall is composed of four “walls” of the heart chambers: the epicardium, the myocardium and the endocardium. The epicardium is a very thin membrane (plasma membrane) that covers the surface of the heart. The endocardium is a continuation of the endovascular membrane and is lined with the inner surface of the myocardium. The folds at the atrial orifice form the mitral and tricuspid valves, and the folds at the aortic and pulmonary orifices form the aortic and pulmonary valves. We often refer to endocarditis as the inflammation that occurs mainly at the valves, such as rheumatic endocarditis and subacute bacterial endocarditis. In between the thin epicardium and endocardium is the thick myocardium, and what we usually call myocarditis refers to inflammatory lesions within the myocardium. This shows that the myocardium is only an important part of the heart wall.
4.What is the conduction tissue of the heart?
A: We call the whole set of conduction pathways starting from the sinus node, through the three inter-nodal bundles to the atrioventricular junction, and then to the left and right bundle branches and Purkinje fibers, the conduction tissue of the heart. The sinus node is a small node under the epicardium at the junction of the right atrium and the superior vena cava, which can give orders to the heart to contract on time; it also goes to another “node” located in the lower part of the atrial septum, which is called the atrioventricular node, and passes through the atrioventricular junction to the left and right bundles, and the left and right bundle branches descend along the deep endocardial surface on both sides of the ventricular septum, and continue to branch. The left and right bundle branches descend along the deep endocardial surface of both sides of the ventricular septum, and continue to branch out, getting finer and finer, finally dividing into tiny “Purkinje fibers” distributed in the myocardium of the left and right ventricles.
5.What is the pericardium?
A: The blind sac that wraps around the heart and the root of the great vessels is called the pericardium. The pericardium is divided into two layers: the epicardium (plasma membrane) immediately adjacent to the heart is called the dirty layer, and the wall layer is composed of the plasma membrane and the outer fibrous layer together. The two layers are closely attached to the root of the great vessels and form a cavity called the pericardial cavity. It contains a small amount of fluid and plays the role of lubrication in the mechanical device.
6.What is the coronary circulation?
A: Coronary circulation, that is, the blood circulation constituted by the arteries and veins that nourish the heart itself. The coronary circulation is the shortest circulation in the body circulation. The blood in the coronary vein mainly flows back to the right atrium through the coronary sinus, and the coronary artery starts from the root of the aorta, which has higher pressure and faster flow rate, and the anastomotic branch between the coronary arteries is relatively small and thin. Dong Nianguo, Department of Cardiac Surgery, Wuhan Union Hospital
7.What is the heart rate of a normal person?
A: In a quiet state, the average heart rate of healthy adults is about 75 times / minute, the normal adult heart rate fluctuates in the range of 60-100 / minute, women’s heart rate is faster than men’s heart rate, physical activity and mental excitement can increase the heart rate. Women’s heart rate is faster than men’s heart rate, but everything is relative, for example, people who often engage in heavy physical labor or physical exercise have a slower heart rate, which can be less than 60 beats per minute, but this can never be said to be a pathological state, and should be considered comprehensively.
8.How to detect heart disease early?
A: It is recommended to have a heart examination when the following phenomena occur in your life, so that heart disease can be detected early and effective measures can be taken.
(1) Palpitations, fatigue, shortness of breath or feeling of breathlessness during physical activity.
(2) Sudden onset of retrosternal pain or chest tightness and pressure during exertion or stress.
(3) Pain in the left chest accompanied by sweating or pain radiating to the shoulder, arm and neck.
(4) Rapid, slow, short or irregular pulse.
(5) Sudden awakening during sleep or nightmares, palpitations, chest tightness, and breathlessness, and the need to sit up for a while to get better.
(6) Difficulty in breathing, chest tightness or chest pain during sexual intercourse.
(7) Palpitations, chest tightness or chest pain during a full meal, cold, smoking, or watching a stressful movie or TV.
(8) Feeling chest tightness, breathlessness and insufficient air especially easier than others in public places or meeting places.
(9) Palpitations and shortness of breath when going upstairs more easily than before or than others.
(10) Sudden palpitations, dizziness, blackness in front of the eyes, and a feeling of falling down.
(11) Children are less active than children of their age, or they feel palpitations, shortness of breath, and weakness during activities, or they have blue lips during activities.
(12) Palpitations and fatigue even after doing some light daily work after catching a cold, or feeling shortness of breath when walking slightly fast.
(13) Sudden chest discomfort and fainting on the floor, or a feeling of “dying” immediately.
(14) Difficulty in breathing at night when the pillow is low, and need to lie on a high pillow.
(15) Swelling of the lower extremities.
(16) Hypertrophy and deformation of the ends of the fingers or toes.
(17) Abnormal color of the face, lips and nails, such as cyanosis or dark red.
(18) Abnormal sound of heartbeat at rest, or tremor when touching the heart area on the anterior chest wall with the hand.
(19) Palpitations, dizziness, shortness of breath or swelling during pregnancy.
(20) Left shoulder pain that does not heal for a long time.