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Old 09-14-2012
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Default Mitral Regurgitation Question

A 46 yr old pt came with easy fatigability and exertional dyspnea. Auscultation reveals a diminished 1st heart sound and an apical holosystolic murmur radiating to the axilla. Lungs have bibasilar crackles. There is no elevation of JVP or peripheral edema. Which would increase forward-to-regurgitant volume ratio?
a. decreasing left vent preload
b. increasing left vent contractility
c. decreasing left vent afterload
d. decrease the heart rate
e. increasing left vent volume


I'm totally confused with this ! Hoping someone can provide a detailed explanation of the answer.

Thanks!
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  #2  
Old 09-14-2012
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Default C

CC...since you could diagnose mitral regurgitation in this patient,the question is asking which intervention could reduce the backflow from Left ventricle into the Right atria during systole.

reducing the afterload will favour foward flow of blood at lesser pressure and reduce regurgitation(option C)
other options will worsen her pathology

hope am right?
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Quote:
Originally Posted by megz2107 View Post
A 46 yr old pt came with easy fatigability and exertional dyspnea. Auscultation reveals a diminished 1st heart sound and an apical holosystolic murmur radiating to the axilla. Lungs have bibasilar crackles. There is no elevation of JVP or peripheral edema. Which would increase forward-to-regurgitant volume ratio?
a. decreasing left vent preload
b. increasing left vent contractility
c. decreasing left vent afterload
d. decrease the heart rate
e. increasing left vent volume


I'm totally confused with this ! Hoping someone can provide a detailed explanation of the answer.



Thanks!
it's c) decreasing left ventricular afterload

from uworld i guess...

it's mitral regurgitation--from holosystolic murmur at apex...

increasing forward to regurgitant ratio implies--decreasing regurgitation

in MR----during systole blood regurgitates into lt. atrium if there is increased left ventricular pressure...so if we decrease lt. ventricular afterload( decrease TPR)----not much pressure needed for ventricle to eject out...leading to decreased regurgitation
we can also decrease preload to decrease regurgitation----but, decreasing preload effects less on lt.ventricular pressure than afterload(preload decrease effect takes place when MR is much severe.)

hope it understands
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Old 09-14-2012
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Question asked in very "wtf" way

Agree
Decrease in afterload will increase forward flow/regurgitant flow ratio
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Old 09-14-2012
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Quote:
Originally Posted by blade View Post
CC...since you could diagnose mitral regurgitation in this patient,the question is asking which intervention could reduce the backflow from Left ventricle into the Right atria during systole.

reducing the afterload will favour foward flow of blood at lesser pressure and reduce regurgitation(option C)
other options will worsen her pathology

hope am right?
Can you explain how this will cause the forward-to-regurgitant volume ratio to reduce? Won't forward and regurgitant volume reduce equally, thus maintaining the same ration?

Also,what if we decrease the LV preload? The EDV now decreases which also causes lesser pressure during systole. So don't Option a and c do the same thing?
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Quote:
Originally Posted by venky2600 View Post
it's c) decreasing left ventricular afterload

from uworld i guess...

it's mitral regurgitation--from holosystolic murmur at apex...

increasing forward to regurgitant ratio implies--decreasing regurgitation

in MR----during systole blood regurgitates into lt. atrium if there is increased left ventricular pressure...so if we decrease lt. ventricular afterload( decrease TPR)----not much pressure needed for ventricle to eject out...leading to decreased regurgitation
we can also decrease preload to decrease regurgitation----but, decreasing preload effects less on lt.ventricular pressure than afterload(preload decrease effect takes place when MR is much severe.)

hope it understands
Thanks so much!
You clarified both my doubt about why the outflow increases and not the regurgitation (but decreasing the TPR) AND why a decrease in afterload is better than decrease in preload.
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Quote:
Originally Posted by megz2107 View Post
Can you explain how this will cause the forward-to-regurgitant volume ratio to reduce? Won't forward and regurgitant volume reduce equally, thus maintaining the same ration?

Also,what if we decrease the LV preload? The EDV now decreases which also causes lesser pressure during systole. So don't Option a and c do the same thing?
yes, we can also decrease preload...but decreasing preload effects less on it..i mean if it's severe MR( if the question clearly mentions it's due to volume overload leading to LVH..then decreasing preload will decrease regurgitation)
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And yes, C is the answer
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Correct Answer

Quote:
Originally Posted by megz2107 View Post
A 46 yr old pt came with easy fatigability and exertional dyspnea. Auscultation reveals a diminished 1st heart sound and an apical holosystolic murmur radiating to the axilla. Lungs have bibasilar crackles. There is no elevation of JVP or peripheral edema. Which would increase forward-to-regurgitant volume ratio?
a. decreasing left vent preload
b. increasing left vent contractility
c. decreasing left vent afterload
d. decrease the heart rate
e. increasing left vent volume


I'm totally confused with this ! Hoping someone can provide a detailed explanation of the answer.

Thanks!
C is the right ans by decrising afterload we will decrese the regurgitation of blood and increase the ejection of blood into aorta
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Old 09-15-2012
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I will go with decreased After load.. which favors better emptying of ventricles and hence Forward flow
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