The document discusses heart sounds and murmurs. It describes the four normal heart sounds: S1 caused by AV valve closure, S2 caused by semilunar valve closure, S3 associated with blood flowing into ventricles, and S4 associated with atrial contraction. It notes S1 and S2 are normally audible. It provides details on S1 occurring with ventricular contraction and AV valve closure, and S2 occurring with ventricular dilation and semilunar valve closure. Heart murmurs result from turbulent blood flow and can be systolic or diastolic, caused by valve stenosis, insufficiency, increased blood flow, or decreased viscosity. The two basic types of valvular disease are stenosis which is

1. Heart Sounds & Murmurs
Dr. Arun Goel
Associate professor
Department of Physiology

2. Heart Sounds

3. Heart sounds
 S1 – “lubb” caused by the closing of the AV valves
 S2 – “dupp” caused by the closing of semilunar valves
 S3 –associated with blood flowing into the ventricles
 S4 –associated with atrial contraction
Four heart sounds can be recorded by phonocardiography,
but normally only the first and the second heart sounds,
are audible through a stethoscope

4. First heart sound
• occurs when the
atrioventricular (AV) valves
close at the beginning of
ventricular contraction
• generated by the vibration of
the blood and the ventricular
wall
• is louder, longer, more in
duration than the second heart
sound

5. Second heart sound
• occurs when aortic and
pulmonary semilunar valves
close at the beginning of
ventricular dilation
• generated by the vibration of
the blood and the aorta
• Aortic valve closes slightly
before pulmonary valve
• Splitting of S2

6. Heart Murmur
• Cardiac murmurs are abnormal heart sounds in the form
of noises resulting from turbulent blood flow,
• Murmurs may be:
– Systolic murmurs, if they occur during systole.
– Diastolic murmurs, if they occur during diastole
• Causes:
– Stenosis (narrowing) of heart valves
– Incompetence of heart valves
– Increase of blood flow or decrease of blood viscosity (as in anemia).

7. Two Basic Types of Valvular Diseases
valvular stenosis:
• narrowing of the valve
valvular insufficiency
(incompetence):
• valve is unable to
close fully; so there is
regurgitation

8. Phonocardiograms examples

9. Thank You