Abn. Heart Sounds

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Click on the number to listen to the abnormal heart sound. Click on the abnormal heart sound to learn more information about that sound.
1=diastolic murmur                  4=pericardial friction rub
2=systolic murmur                    5=S3 (ventricular gallop)
3=mid-systolic click

Diastolic Murmur-murmur that occurs in the filling phase of the
cardiac cycle.  Incompetent semilunar valves or stenotic AV valves
cause a diastolic murmur.  These murmurs almost always indicate 
heart disease.  Early diastolic murmurs usually result from
insufficiency of a semilunar valve or dilation of the valvular ring.
Mid-and late diastolic murmurs are generally caused by narrowed,
stenosed mital and tricuspid valves that obstruct blood flow.  A
loud murmur that is accompanied by a thrill usually indicates a 
pathologic condition.

Systolic Murmur-murmur occurring during the ventricular 
ejection phase of the cardiac cycle.  Most systolic murmurs are
caused by obstruction of the outflow of the semilunar valve
(aortic, pulmonic) or by incompetent AV valves (mitral, tricuspid).
The vibration is heard during all or part of systole.  Other possible
causes of systolic murmurs are structural deformities of the aorta
or pulmonary arteries.  A ventricular septal defect results in a 
murmur classified as pansystolic or holosystolic because it occupies
all of systole.

Mid-systolic Click-this sound is associated with mitral valve 
prolapse; in which the mitral valve leaflets not only close with 
contraction but their is a balloon back up into the left atrium.  
During ballooning, the sudden tensing of the valve leaflets and the
chordae tendineae creates the click.

The sound occurs in mid to late systole and is short, high-pitched,
with a click quality.  It is best heard with diaphragm, at the apex,
but also may be heard at the left lower sternal border.  The click
is usually followed by a systolic murmur.  The click and murmur 
move with postural changes.  When a person assumes a squatting 
position or uses the Valsalva maneuver, the click may move closer
to S2, and the murmur may sound loud and delayed. 

Pericardial Friction Rub-this sound is caused by a rubbing 
together of the inflamed visceral and parietal layers of the
pericardium; This rubbing sound is usually present in both systole
and diastole and is best heard over the apical area (apex).  Can be
heard during inspiration or expiration and does not change with 
the respiratory cycle. May be present in conditions such as 
pericarditis.  

S3 (Ventricular Gallop)-Normally diastole is a silent event.  
However, in some conditions, ventricular filling creates vibrations
that can be heard over the chest.  These vibrations are the S3 
heart sound.  The S3 heart sounds occurs when the ventricles are
resistant to filling during the early filling phase.  This sound occurs 
immediately after the S2 when the AV valves open and the atrial
blood pour into the ventricles.

The S3 heart sound is a soft, low pitched sound.  It is best heard at
the apex with the bell held lightly with the person in the left 
lateral position.  An S3 sound may be normal (physiologic) or 
abnormal (pathologic).  The physiologic S3 is sometimes heard in 
children and young adults. The normal S3 usually disappears when 
a person sits up.  In adults over age 40, the S3 is usually abnormal.
The pathologic S3 is also called a ventricular gallop and persists 
when the person sits up.  The pathologic S3 indicates decreased 
compliance of the ventricles, as in CHF and may be the earliest 
sign of heart failure. The pathologic S3 occurs during other 
conditions of volume overload such as mitral regurgitation, aortic 
regurgitation as well as in high cardiac output states in the absence
of heart disease such as hyperthyroidism, anemia, and pregnancy. 
When the primary condition is corrected, the S3 gallop disappears.