Aortic regurgitation produce three type of
murmurs
Describe
the classical murmur of AR (EDM)
1. Classical
murmur of AR is a high pitched blowing descrendo murmur
2. Best
heard in 2nd aortic area
3. Patient
leaning forward
4. Breath
held in expiration
Why
the murmur of AR is early diastolic in nature
Because the pressure in aorta is more than left ventricle
during early part of systolic, which equalises in the middle part of diastolic
.
Frequency
of murmur
It is due to high velocity of flow and due to small
regurgitant volume.
Intensity
of murmur
Mild AR - Soft murmur is heard
Severe AR - loud murmur is heard
These relation need not be
true always
Duration
of murmur
Mild AR – Murmur is
confined to early part of diastole
Severe AR – Murmur is
haldiastolic and descrendo in nature
Site
of murmur
1. Normally
heard in the 2nd and 3rd right intercostals space.
2. May be
conducted down to lower sternal border.
3. In AR due
to aortic root dilatation, it may be heard down the right sternal border.
4. In
elderly people it may be heard at the apex.
What
are the techniques that increases the audibility of murmur
1. Hand grip
2. Squatting
3. Simultaneous
application of pressure cuffs to both arms for about 20 seconds to a level of
20mm above the systolic blood pressure.
Why
the murmur is early diastolic in severe AR with LV dysfunction
Severe AR with LV dysfunction produce high left ventricular
end diastolic pressure, which decreases the aorta to left ventricular gradient
in the later part of diastolic as the murmur will decrease.
Ejection
systolic murmur in AR
It is produced due to rapid ejection of increased stroke
volume through the abnormal valve.
Even though the murmur may be loud – it need not imply the
associated AS.
Austin
flint murmur
Mention the causes
of absent murmur in AR
Low cardiac output
Cardiac failure
Pulmonary artery
hypertension
Other valvular
lesion
Mitral stenosis
Mitral regurgitation
Others
COPD
Obesity