Download Rate and sound of heart

Rate and sound of heart
Objective:to hear sound and determine the rate of heart
Introduction:
The heart consists of four chambers,two atrium and two ventrical.the ventricales plays the major part in circulating the
blood.the characteristic heart sound is lup-dup pause-lup-dup pause rhythm.two sounds are normally heard during cardiac
cycle by stethoscope,other low frequncey sounds are detected by phonocardiogram.
The first heart soundcaused by sudden closure of the mitral and tricuspidvalves at the start of ventrical systole.it is heard as
lub,low pitch 25-45Hzand prolong time 0.14-0.15.
The second heart sound caused by closure of aortic and pulmonary valves,high pitch 50 Hz ,shorter time 0.11 second.it
occurs at beginning of diastolic.it is heard as dup.
The third heard sound it is caused by rapid Ventricular filling and inrush of blood, soft heard by stethoscope .
The fourth sound it is caused by atrial contraction due to inrush of blood
into ventricales.it occurs immediately before first heart sound at end of diastolic.it is not heard by stethoscope.
In each heart beat, ventrical pumus out about 70 ml of blood.this volume is termed astroke volume the heart beat is about
70-75 times per minute,this is heart rate.in animals the heart rate depends on species, size and age .the heart rate increase in
young animals than old animals.during exercise the heart rate and stroke volume increase.during sleep the heart rate
diminishes by 10-20beats per minutes.
Animals
heart rates
Horse
32-60
Cow
60-70
Sheep
70-80
Dog
70-120
Cat
110-130
Chicken
200-400
Instruments Materials and
Subject
Stethoscope:it is composed of
Ear-pieces.
Plastic tube
Diaphragm and chest bell
Ear pieces should be well fitting,extraneous noises must be excluded.tubes should be small in diameter and short to reduce
loss of conduction by friction.
Procedure
-put the chest bell or diaphragm of your stethoscope on apex area.
-heard the sound of heart
-mention any abnormal sound or murmur you are heard
Calculate heart rate