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Describe the murmurs in aortic regurgitation

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