Auscultation of Heart sounds

first heart sound

closing of Atrioventricular valves (Tricuspid Valve, Mitral Valve)

characteristics of the first heart sound

Low pitched (25 - 45 Hz)

Longer duration (0.14 Sec)

Give the sound of Lub

Mitral area

5th intercostal space, medial to the midclavicular line. Apex of the heart

Tricuspid area

between 4th and 5th space close to lower left quadrant of sternum

second heart sound

closure of semilunar valves (Aortic and pulmonary valves).

characteristics of the secoond heart sound

High pitched( 50 Hz)

Shorter duration( 0.11 sec)

Give the sound of Dub

Aortic area

2nd intercostal space, right sternal border

pulmonary area

2nd intercostal space, left sternal border

third heart sound

Caused by rushing blood flow from atria to ventricles.

gallop

reason for S3

Physiological causes: Normally heard in most children, athletes and pregnant female.

Pathological causes: congestive heart failure, aortic regurge and dilated cardiomyopathy

Fourth Heart Sound

atrial contraction, vibration of ventricular wall which occurs at the end of ventricular diastole

reason dor s4

Occurs in concentric ventricular hypertrophy (Stiff ventricular wall)

stethoscope

a medical instrument for listening to the sounds generated inside the body

parts of stethoscope

ear pieces, binaurals, tubing, chest piece: diaphragm, bell