The right atrium contains the venous blood of the whole body and is pumped out from the pulmonary artery through the right ventricle. At this time, venous blood flows in the pulmonary artery. Through the gas exchange in the lungs, it becomes oxygen-rich arterial blood, which is sent from the pulmonary vein to the left atrium, and then through The aorta of the left ventricle pumps to various tissues and organs of the body to meet the needs of its normal physiological activities.
The role of the heart is to promote blood flow, provide adequate blood flow to organs and tissues, to supply oxygen and various nutrients, and to take away the end of metabolism.
Products (such as carbon dioxide, urea and uric acid, etc.) enable cells to maintain normal metabolism and function. Various endocrine hormones and some other bodily fluid factors in the body also need to be transported to target cells through blood circulation to achieve the body fluid regulation and maintain a relatively constant body environment. In addition, the realization of the blood defense function and the regulation of a relatively constant body temperature also depend on the continuous circulation of blood in the blood vessels, and the circulation of blood is realized by the heart "pump". The heart of an adult weighs about 300 grams, and its effect is huge. For example, when a person is in a quiet state, the heart beats about 70 times per minute, and pumps 70 ml of blood each time, then about 5 liters of blood is pumped per minute. The work done by a person's heart to pump blood in a lifetime is approximately equivalent to the force required to lift an object weighing 30,000 kilograms up to the top of the Himalayas.
Every beat of the heart relies on electrical signals from the heart to operate. The Supreme Command is something called the sinoatrial node. The commands it sends control the rhythm and frequency of the heart; this command transmits electrical signals to various locations in the heart through a telephone line-like conduction system. When the signal is transmitted to the atria, it causes the atria to contract, so blood is pumped into the diastolic ventricles; when the signal is transmitted to the ventricles, the ventricles contract, causing the right ventricle to pump blood to the lungs, and the left ventricle to pump blood Pump to the whole body. The electrical signal from the atrium is transmitted to the left and right ventricles through a structure similar to a substation called the atrioventricular node, and then through a structure similar to conductive wires called the left and right bundle branches. All these constitute the heart's command and communication system. If a problem occurs in the heart command and communication system due to various reasons, a heart rhythm disorder will occur, also called arrhythmia.