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There's a table in Kaplan Lecture Notes which summerizes the effects of various maneuvers on the systolic murmurs of aortic stenosis, hypertrophic obstructive cardiomyopahty, VSD, and mitral regurg.

I am finding hard times memorizing it. And also I can't understand the underlying pathophysiology as it's not explained. And also what's handgrip?

Please if you can share your thoughts about that terrible table.

Thanking you in advance
 

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Pathophysiology and memorizing that table

I don't think that table is really important for the CK exam. Exam cases are usually differentiated on the basis of other more important characteristics and patient's history rather than merely the effects of these maneuvers.

However, here's some help with table.

First of all swipe off the middle column "Squatting". The lateral four columns are just opposite each other. Valsalva is the opposite of leg raising and that makes sense because Valsalva decreases venous return while leg raising increases venous return. Phenylphrine is the opposite of Amyl Nitrite that makes sense because the first is a constrictor while the other is a dilator.

Take phenylphrine in AS. You'll see that the murmur decreases this is because you constricted the arterioles and so you increased the preload and so less flow across the aortic valve (therefore more flow in the other channels like flowing back through MR or through VSD increasing the intensity of their respective murmurs). Once you memorize this then everything else is a game of oppisites. 2nd column opposite of 4th and 1st column opposite of 5th column. Likewise, AS/HOCM opposites of VSD/MR. The only exception to this rule is HOCM in Valsalva and Leg raising.

Hope this helps a little.

But as I told you don't spend time trying to memorize. It's not going to benefit you on the exam.
 

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I don't think that table is really important for the CK exam. Exam cases are usually differentiated on the basis of other more important characteristics and patient's history rather than merely the effects of these maneuvers.

However, here's some help with table.

First of all swipe off the middle column "Squatting". The lateral four columns are just opposite each other. Valsalva is the opposite of leg raising and that makes sense because Valsalva decreases venous return while leg raising increases venous return. Phenylphrine is the opposite of Amyl Nitrite that makes sense because the first is a constrictor while the other is a dilator.

Take phenylphrine in AS. You'll see that the murmur decreases this is because you constricted the arterioles and so you increased the preload and so less flow across the aortic valve (therefore more flow in the other channels like flowing back through MR or through VSD increasing the intensity of their respective murmurs). Once you memorize this then everything else is a game of oppisites. 2nd column opposite of 4th and 1st column opposite of 5th column. Likewise, AS/HOCM opposites of VSD/MR. The only exception to this rule is HOCM in Valsalva and Leg raising.

Hope this helps a little.

But as I told you don't spend time trying to memorize. It's not going to benefit you on the exam.
Does Increasing afterload intensify murmer of MVP or decrease it like HOCM ??? What is the mechanism of so in MVP ?
 

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cardiac murmurs

Does Increasing afterload intensify murmer of MVP or decrease it like HOCM ??? What is the mechanism of so in MVP ?
Increasing afterload will intensify the murmur of MVP as there is an obstruction to LV emptying so there is more regurgitation during that time into the LA as that is a path of less resistance .
In HOCM the IVS is hypertrophied and obstructs the outlet by the anterior mitral valve leaflet and hence obstructs LV outlet. This obstruction will be enhanced if LV volume is decreased and murmur will increase.Hence in HOCM the preload will determine the intensity of murmur.
 
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