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•Cardiac (heart) murmurs are pathological sounds usually produced in an affected heart.
• The main mechanism of the heart murmurs is the turbulent flow of the blood, caused by the
obstacles in the blood flow.
So, the causes of the heart murmurs are:
An obstacle in the blood flow because of a narrowed lumen (narrowed vessel or narrowed valve orifices);
An enlarged passage (a dilated vessel – aneurism)
Sometimes murmurs can be caused by the changed properties of the blood – decreased viscosity of the blood or increased speed of the blood flow – so-called functional murmurs.
According to the origin there could be 2 types of cardiac murmurs:Endocardiac - arise inside the heart; occur
more frequently;Extracardiac- arise outside the heart
Endocardiac murmurs may be organic or functional. Organic murmurs : - due to anatomical changes in the structure of
the heart valves (stenosis, incompetence); Functional murmurs are produced: - due to dysfunction of the intact valves. For
example: due to the dilatation of the left ventricle the mitral orifice will be dilated and the mitral valve will not close completely the mitral orifice;
- due to increased speed of the blood flow (for ex. - in hyperthyroidism)
- due to decreased blood viscosity (for ex.. – in anemia).
According to timing of appearance cardiac murmurs can be:1. Systolic2. Diastolic
Systolic murmur appears during cardiac systole: Stenosis of the aortic orifice Stenosis of pulmonary trunk Regurgitation of blood through an
incompletely closed orifice during ventricular systole (mitral regurgitation and tricuspid regurgitation.)
Diastolic murmur occurs during diastole. In stenosed left or right atrioventricular
orifice, since blood meets a narrow passage in its flow from atria to ventricle.
Aortic or pulmonary valve regurgitation when the blood flows back from the vessels to the ventricles through the slit formed by incomplete closure of the cusps of the affected valves.
Systolic murmurs occur with the S1, during the short pause of the heart; they are synchronized with the heart beat and carotid pulse. Diastolic murmurs occur during the long pause of the heart and follow S2
Three types of systolic murmurs are distinguished:1. protosystolic (early systolic)- appears at
the beginning of systole, after the S12. midsystolic - occurs soon after the S13. late systolic - at the end of systole
Three types of diastolic murmurs are distinguished:1. protodiastolic (early diastolic) - appears
at the beginning of diastole, after the S22. middiastolic - occurs soon after the S23. presystolic (late diastolic)- at the end of
diastole
To characterize the cardiac murmur, during auscultation the following should be determined:
Localization of the murmur The relation of the murmur to the phase of
the heart activity (to systole or diastole) – to appreciate it is a Systolic or a Diastolic murmur;
The features, character, the length and strength of the murmur
Irradiation of the murmur
Properties of the murmurs.By their character, murmurs can be - soft,
blowing or rough, grating or grazing sounds, musical murmurs.
By duration – short or long;By intensity - low or loud.
Configuration of murmur may be:CrescendoDescrescendoCrescendo – Descrescendo (diamond-shaped)PlateauMurmur may become weaker (descrescendo)
and louder (crescendo).
Murmur Patterns
• Common systolic– Crescendo-decrescendo– Holosystolic
• Common diastolic– Decrescendo– Holodiastolic
Systole Diastole
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Common Murmurs and Timing
Common Murmurs and Timing
Systolic Murmurs• Aortic stenosis• Mitral insufficiency• Mitral valve prolapse• Tricuspid insufficiency Diastolic Murmurs• Aortic insufficiency• Mitral stenosis
S1 S2 S1
Plateau-like, Pan-Systolic, Quiet S1, Blowing, High-Pitched, Heard at Apex, Radiates to Axilla,
Diastolic murmur due to mitral stenosis is usually heard in limited apex area.Auscultative picture mitral stenosis, Diastolic, Low-Pitched,
Heard over Apex.
Auscultative picure of aortic stenosis. Crescendo-Decrescendo, Ejection systolic, Loud, Rough, Medium Pitched, Heard over Aortic Area, Radiates to Carotids
Auscultative picture of aortic regurgitation. Early-Diastolic, Low-pitched, Heard over Apex.
Differentiation of murmursSystolic and diastolic murmurs over the same
valve indicate its associated affection, i.e. insufficiency of the valve and stenosis of the orifice.
If systolic murmur is heard over one valve and diastolic murmur over the other, a combined affection of two valves can be diagnosed.
. The following properties of functional murmurs help to differentiate them from organic murmurs:
Most cases functional murmurs are systolic 2. Functional murmurs are not permanent and may arise
and disappear when the person changes its posture, after exercise and during respiratory phases.
3. They are mostly heard over the pulmonary trunk and less frequently over the heart apex
4. Functional murmurs are transient and are rarely heard during the entire systole, they are soft and blowing sounds
5. Functional murmurs are normally heard over limited area and are not transmitted to long distances from the place of formation
6. Functional murmurs are not accompanied by other signs of valve affections, i.e. changes of the sound
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