Archive for the ‘ Pract-Heart Sound ’ Category

Pract- Heart Sound

Introduction

Learning objectives:

1.Know types of normal heart sounds.

2.Know the abnormal heart sounds e.g. murmurs.

3.Know the methods used to detect normal and abnormal heart sounds

4.Demonstrate, on a living person , where a stethoscope should be placed to auscultate for heart sounds or murmurs

Remember that:

The classical sequence of clinical examination is;

1.Inspection (look)

2.Palpation (feel)

3.Percussion (tap)

4.Auscultation (listen)

Normal Heart Sounds

•There are 4 sounds produced by the heart that are produced vibrations of the cusps of the heart valves.

•4 cardiac valves;

1)  2  Atrioventricular (AV) valves (tricuspid and mitral valves)

1)  2 semilunar valves (aortic and pulmonary valves)

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Methods of Detection of Heart Sounds

a)Stethoscope:

2 sounds are only audible by stethoscope

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b) Phonocardiograph:

records for 4 sounds → phonocardiogram

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Types of Normal Heart Sound

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Abnormalities of Heart Sounds

1)Splitting (duplication) of HS:

Def.,

The HS is heard as 2 sounds separated by a very short interval.

Causes:

It is due to asynchronous closure of  valves on both sides of the heart.

a)Splitting of the 1st HS:

—It is due to asynchronous closure of the mitral and tricuspid valves.

—Closure of the TV slightly precedes the closure of the MV

b)Splitting of the 2nd HS:

—It is due to asynchronous closure of the aortic and pulmonary valves.

—The aortic valve closes slightly earlier than the pulmonary.

—This is observed during inspiration.

NORMAL

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SPLITTING SOUND

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2) Triple or gallop rhythm:

Def.,

It is an abnormal condition in which three heart sound are heard resembling the sound of a galloping horse.

Causes and types:

It occurs in heart failure, it is either;

1.Protodiastolic gallop

→ if the third heart sound is the 3rd sound.

2.Presystolic gallop

→ if the 4th heart sound is the 3rd sound.

3) Murmurs:

Def.,

They are abnormal noisy sounds heard over the heart other than the heart sounds.

Mechanism of murmurs:

—They are caused by change in the rate of blood flow:

—The blood flow in vessels may be;

i)Streamline or laminar flow:

—The blood flows in layers or laminae which is faster in the center and slow at the periphery.

ii)Turbulence flow:

—In which there is an eddy current, i.e. not all particles move in the same moment.

—The agitation of fluid particles produces a noisy or murmur.

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Types of murmurs:

It includes 3 types as follow;

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1-Systolic murmurs

(Functional)

———

(Organic)

1)Sternosis

a) Aortic

b) Pulmonary

2)Regurgitation

a) Mitral

b) Tricuspid

3)VSD

2-Diastolic murmurs

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1)Sternosis

a) Mitral

b) Tricuspid

2)Regurgitation

a) Aortic

b) Pulmonary

3-Continuous murmurs

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Patent Ductus Arteriosus

4-Others

1) Opening Snap

2)Mid Systolic Click

Instrument

Stethoscope

PARTS

It consists of 3 parts:

a. Chest piece

→ consists of 2 parts

  1. Cone of bell → for low pitched sounds
  2. Diaphragm →for high pitched sounds

b. Ear pieces.

c. Rubber tube

(50-75 cm).

Uses of stethoscope:

1. Auscultation of heart sounds.

2. Auscultation of breath sounds

3. Auscultation of intestinal sounds

4. Measurement of ABP.


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