Nowadays, the probability of developing cardiovascular diseases is constantly increasing. These diseases mainly harm the function of the human heart, so everyone should have a certain understanding of the functions of the heart and the diseases that are prone to occur. However, it should be noted that these diseases are also chronic diseases, so it is important to pay attention to lifestyle habits. Below, the editor will take you to pay attention to a question, the second characteristic of heart sounds.
Characteristics of the second heart sound
1. The second heart sound indicates the beginning of ventricular dilation, around the end or later of the electrocardiogram T wave. The second heart sound on the electrocardiogram is also composed of four components, among which the second component is a higher frequency and amplitude vibration, which is the audible component of the second heart sound. The cause of the second component of the second heart sound is generally believed to be the sudden deceleration of blood flow in the aorta and pulmonary arteries, as well as the sudden closure of the semilunar valve causing valve vibration. Other factors such as the opening of the atrioventricular valve are also involved in the formation of the second heart sound.
2. The second component of the second heart sound can also be divided into two parts: the aortic valve that closes in the front forms the aortic part of the sound, and the pulmonary valve that closes in the back forms the pulmonary valve part of the sound. Similarly, these components cannot be distinguished by the human ear, and auscultation is only collected and organized by one sound medical education website. The auscultatory characteristics of the second heart sound are a relatively high and crisp tone, weaker intensity than S1, shorter duration (about 0.08s), not synchronized with the apical beat, and the loudest sound in the heart.
What is the second heart sound
1. Heart sound is a mechanical vibration caused by factors such as myocardial contraction and relaxation, valve opening and closing, blood flow impacting the ventricular wall and large arteries during the cardiac cycle. It is transmitted to the chest wall through surrounding tissues and heard by placing the ear close to the chest wall or placing a stethoscope in a certain part of the chest wall. It is usually easy to hear the first and second heart sounds, and sometimes the third or fourth heart sound can be heard in certain situations.
2. Second heart sound: occurs at the beginning of the diastolic phase of the heart, with a high frequency and a short duration (about 0.08 seconds). The reason for this is the closure of the half moon valve, the collision of valves with each other, and the vibration caused by blood deceleration and rapid decrease in indoor pressure in the large arteries. The optimal auscultation sites for the second heart sound are the pulmonary valve area on the left side of the second intercostal space and the aortic valve area on the right side.
The above is the information compiled by the editor regarding the characteristics of the second heart sound. The editor believes that medicine is the closest discipline to life, but everyone is not a doctor, so everyone needs to have a general understanding of some diseases and treatment methods in medicine, especially the diseases that teachers encounter on themselves. This way, one can accumulate enough knowledge to deal with life's problems.
