e-learning "Auscultation".

Top | (i) The most careful points to perform Auscultation | (ii) Auscultation Sites | (iii) Various positions in Auscultation

	a) Auscultation of carotid artery


	The auscultation of the carotid artery is particularly important for the aged person if the patient complains of a recent episode of vertigo or fainting. These symptoms may be due to "carotid arterial stenosis," and the examiner is able to hear "bruit" on the carotid artery. If the stenosis is severe, the examiner can hear "sustained bruit." If aortic stenosis is present, bilateral bruit can be heard on the neck.

	b) Auscultation of the Aortic Area


	Notice the relationship of I (S1) and II heart sounds (S2). In a healthy individual, the S2 is louder than S1 in "aortic stenosis," and you can hear the midsystolic ejection murmur over the aortic area to the carotid artery. In "aortic regurgitation," you can hear the systolic ejection murmur and early diastolic regurgitant murmur in this area.

	c) Auscultation of the Pulmonic Area


	Auscultatory findings in the pulmonic area are the same as the aortic area, however, the splitting of S2 is particularly important. On inspiration, the S2 splits 0.02 ~ 0.03 sec, and returns to normal on expiration. The reason why S2 splits on inspiration is the right ventricle becomes larger with inspiration because inspiration lowers the intra thoracic pressure, and causes more blood to be drawn from the vena cava to the right atrium, and it takes more time to expel blood into the pulmonary artery. In healthy individuals, "innocent" murmur is audible in this area.

	d) Auscultation of the Tricuspid Area


	In the tricuspid area, S1 and S2 are of the same loudness and/or S1 is somewhat louder than S2. You can also hear the splitting of S1 and a click sound. In mitral stenosis, the opening snap can be heard. In tricuspid regurgitation, the pansystolic murmur increases on inspiration, and decreases on expiration. A prominent early diastolic regurgitant murmur of the aortic regurgitation is heard in this area.

	e) Auscultation of the Mitral Area


	In the mitral area, S1 is louder than S2. You can also hear S3 and S4 in this area in the left lateral recumbent position. Particularly, in mitral stenosis, you can hear the opening snap, followed by a mid-diastolic rumbling murmur in this area. Also, in MR, you can hear the pansystolic murmur of the mitral regurgitation, followed by S3.

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Auscultation at base

Press the diaphragm of the stethoscope on skin and listen.

Fixed the splitting of S2

Press the diaphragm on the pulmonic area and listen (supine position) .

As shown in the above figure, the S2 splits on inspiration and there is no splitting on expiration. The examiner should place his (her) stethoscope firmly on the pulmonic area. On inspiration, healthy person shows respiratory (physiological) splitting of 0.02 - 0.03 sec on inspiration. In ASD, S2 split is relatively fixed. The reason is due to changes of blood volume through foramen, on inspiration and expiration. And the shunted blood volume becomes almost constant. Strictly speaking, there are slight changes observed clinically.

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