phonocardiogram

The method of recording the vibration generated during the heart activity through the special electronic instrument, the heart sound map machine, from the chest wall to the line pattern is called the heart sound map check. The recorded figure is the body surface sound map, referred to as Heart sound map. (1) Verify the heart hearing clinic and supplement the auscultation. (2) Determine the time at which heart sounds or murmurs occur in order to distinguish between heart sounds and murmurs that are clinically confusing. (3) Depicting the shape of the noise, such as a diamond shape, a decreasing shape, and the like. (4) Assist in the diagnosis of certain cardiovascular diseases, identify some intracardiac diseases with similar surface lesions and different lesions, such as coronary heart disease (change of 4th heart sound-S4 before and after exercise), estimation of mitral stenosis, pulmonary valve The difference between stenosis (valve or funnel), patent ductus arteriosus, and major pulmonary artery defects. (5) The components that constitute the non-invasive examination of the heart, the heart sound map combined with echocardiography, carotid pulsation, and apical beat map can be used to estimate hemodynamic changes and cardiac function in certain cardiovascular diseases. The mechanism of heart sounds and murmurs can also be studied, and some pathophysiological changes can be inferred. (6) The heart sound map turns the heart sound and the murmur into a graph that can be stored for a long time, and can be used as an objective indicator for judging the change of the lesion and comparing the curative effect of the surgery or the drug. However, the heart sound map can not be auscultated, it can not distinguish the sound source from the heart is the heart, and can not distinguish the sound of heart sounds and noise (such as rumbling or blowing). The heart sounds and murmurs revealed by the heart sounds are sometimes invisible to the human ear, but sometimes the heart sounds that can be heard by the human ear cannot be remembered (such as some diastolic murmurs of the aortic valve). The human ear is sensitive to high frequencies, if necessary. With the help of a stethoscope. Basic Information Specialist classification: cardiovascular examination classification: electrocardiogram Applicable gender: whether men and women apply fasting: not fasting Tips: The laboratory must be quiet. The patient must eliminate tension and quietly cooperate with the medical staff to complete the examination. Normal value The first heart sound (S) corresponds to 0.02 to 0.04 seconds after the start of the QRS wave on the electrocardiogram, and takes about 0.08 to 0.135 seconds. It is caused by ventricular contraction, mitral regurgitation, tricuspid valve closure and ventricular contraction, blood flow into the large blood vessels. The second heart sound (S) is equivalent to the end of the T wave on the electrocardiogram. It is caused by ventricular wall vibration when the ventricle is dilated, blood flow from the atrium into the ventricle when the aortic valve and the pulmonary valve are closed and the atrioventricular valve is open. The third heart sound (S) is equivalent to a distance T of 0.12 to 0.20 seconds after the T wave on the electrocardiogram, and takes 0.05 seconds, and the frequency and amplitude are low. It is caused by rapid filling of the ventricle and vibration of the ventricular wall. The fourth heart sound (S) is equivalent to 0.18 to 0.14 seconds after the P wave of the electrocardiogram, and the amplitude is low because the blood flow rapidly enters the ventricle and vibrates the ventricular wall when the atrium contracts. Clinical significance The heart sound map can truly record normal heart sounds, extra heart sounds, and heart murmurs. The application of heart sound map and cardiac auscultation can complement each other. Heart sounds increase or decrease The first heart sound enhancement is seen in hyperthyroidism, hyperthermia, mitral stenosis, and ventricular hypertrophy. The first heart sound is weakened in myocarditis, myocardial infarction, mitral regurgitation, and aortic regurgitation. The second heart sound in the aortic valve area is weakened in hypertension and aortic sclerosis. The second heart sound enhancement in the pulmonary valve area is seen in mitral stenosis, left ventricular dysfunction, and left to right shunt congenital heart disease. Attenuation of the second heart sound in the aortic valve area is seen in aortic stenosis or insufficiency. The second heart sound in the pulmonary valve area is weakened in pulmonary stenosis or insufficiency. Heart sound split The first heart sound split is caused by the closing time of the mitral and tricuspid valves, which is caused by a difference of 004 ​​seconds or more. Common in the right bundle branch block. The second heart sound split is caused by the off time of the aortic valve and the pulmonary valve being out of sync, which is caused by a difference of more than 0035 seconds. Common in mitral stenosis, atrial septal defect, arterial catheter closure, right bundle branch block, primary pulmonary artery expansion. Noise (1) degree of noise The high amplitude is greater than the first heart sound. The low amplitude is less than 1/3 of the first heart sound. The mid-amplitude is between high and low amplitude. Very low amplitude, slight vibration. (2) Noise form Can be divided into consistent, declining, incremental, diamond and amorphous. (3) Types of noise and its clinical significance Diastolic stenosis murmurs are low-frequency, progressive, mostly in the middle of diastole. Common in mitral stenosis. Diastolic reflux murmurs are high frequency and decreasing. Common in aortic regurgitation and pulmonary regurgitation. Systolic reflux murmurs have high frequency and consistent type occupying full systole. Common in mitral regurgitation or tricuspid regurgitation. The systolic jetting noise has a high frequency and a rhombic amplitude. Common in aortic stenosis, pulmonary stenosis, ventricular septal defect and so on. Continuous frequency murmurs, increasing type, accounting for all systolic and diastolic phases, are common in patent ductus arteriosus. Additional tone (1) Shrinking early jet sound A short tone with high frequency and high amplitude after the first heart sound. The vibration caused by the sudden opening of the valve being opened due to contraction of the early ventricular ejection to the large blood vessels. Found in pulmonary hypertension, pulmonary artery dilatation, pulmonary stenosis, aortic stenosis, high blood pressure and so on. (2) contraction of middle and late clicks It is an additional sound with high frequency and short time. Due to the systolic mitral valve into the left atrium, the chordae and the valve are caused by tension. Found in mitral valve prolapse, coronary heart disease, papillary muscle dysfunction. (3) Early diastolic galloping (ventricular galloping) The second heart sound starts from 0.15 to 0.17 seconds and is caused by a bloody shock to the left ventricular wall of the lesion. Found in acute left heart failure, myocarditis, myocardial infarction and so on. (4) galloping before the systolic period (atrial galloping) The frequency is low due to increased ventricular end-diastolic pressure and decreased left ventricular wall compliance. Found in coronary heart disease, left heart dysfunction and so on. (5) open sound The frequency is high and the duration is short. Caused by a sudden stop of early diastolic opening of the atrioventricular valve. Found in the mitral valve stenosis is still flexible. (6) Pericardial slamming sound The frequency and amplitude are low, after the second heart sound. Due to ventricular diastolic limitation, ventricular dilatation suddenly stops and the ventricular wall vibrates. Seen in pericarditis. Precautions The laboratory must be quiet. The patient must eliminate tension and quietly cooperate with the medical staff to complete the examination. Inspection process Checked by a special electronic instrument, the heart sound map machine. Not suitable for the crowd Inappropriate people: Generally there are no people who are not suitable. Adverse reactions and risks Generally no adverse reactions.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.