When the heart works, a number of sound phenomena arise , which are studied using auscultation. Auscultation of the heart provides an opportunity to get an idea of the processes occurring in the heart during its work. When conducting this study, you must adhere to the rules that increase its effectiveness:
- The heart must be heard in horizontal and vertical position, sometimes on the left side;
- Auscultation of the heart can be performed with normal breathing of the patient. If it is necessary to clarify a number of points, they also listen to it with a breath hold ;
- when listening, it is necessary to maintain silence and the room should be warm;
- the valves are heard in order to reduce the frequency of their defeat.
Auscultation of the heart is carried out by the generally accepted method of listening with a stethoscope or phonendoscope. Using these tools makes it possible to determine sound phenomena from different parts of the heart, which is especially important in connection with their close location. Some sounds during the work of the heart are better heard during auscultation directly with the ear.
For a correct assessment of the auscultatory picture, it is necessary to know the areas of projection of the heart valves, the areas of their best listening. The perception of sounds generated during the work of the heart depends on the location of the projection of the valves, the conduct of sound vibrations in the blood flow, and the location in the chest of the part of the heart in which these vibrations are formed. This makes it possible to find certain areas on the chest where better sound effects can be heard. The best listening areas of the heart are called auscultation points.
Auscultation of the heart - listening points
Listening to the heart is carried out in a certain sequence, which is followed for the correct assessment of the data obtained. For this, auscultation points of the heart are used, that is, sections of the chest where the sounds formed in a particular section of the heart are better heard.
First point. First, the mitral valve is heard . Auscultation is performed at the first point, which is located at the apex of the heart.
Second point. Then listen to the operation of the aortic valve - in the second intercostal space to the right of the sternum.
Third point. Auscultation of the valves of the pulmonary trunk is carried out in the second intercostal space to the left of the sternum.
Fourth point. Listening to the work of the tricuspid valve is performed at the base of the sword-shaped process of the sternum.
These are the main four points of auscultation. There are additional ones that are used to refine the data when any changes are detected.
Normally, two short, constantly alternating sounds, which are called heart tones, are heard over the area of the heart.
The first tone is formed during the contraction of the ventricles, that is, systole, and therefore is called systolic. It is longer and lower, appears after a long pause, listens better above the apex, coincides with the arterial pulse.
The second tone is called diastolic, as it occurs during relaxation of the heart - diastole. The diastolic tone is heard after a short pause, is better heard above the base of the heart, it is short and high in sound.
Pathological changes in the heart lead to the fact that cardiac tones can change: amplify, weaken, bifurcate, additional third and fourth tones appear. For example, with a significant weakening of the contractile function of the myocardium, a third tone appears, and the work of the heart is characterized by the rhythm of a gallop, as it resembles the sound of the stamping of horses.
Auscultation of the heart can reveal cardiac murmurs that form between heart tones during systole or diastole. Cardiac murmurs are divided into intracardiac and extracardiac, as well as functional and organic. They are soft and rough, quiet and loud. Noises are heard well at the points of auscultation of the heart.