Hypertrophic cardiomyopathy - simran88

[ArchivalUser]

In uworld it says, "systolic ejection murmur of hypertrophic cardiomyopathy would decrease w/ hand grip exercise"...is this because less blood would flow through aorta b/c of the increased resistance?

[ArchivalUser]

The murmur intensity decreases because there's a increased preload, therefore opens outflow track.

Murmur int. decreases with icreased preload (reclining, drigs decreasing contractility, sustained clenching of hands, squatting.

Remember that in this pathology the murmur intensitivity increases
(obstriction worsens) with decreased preload (standing up, valsalva man. inotropic drugs.)

[ArchivalUser]

I don't understand how clenching of hands would increase preload? I thought it would just increase afterload?

[ArchivalUser]

I guess with the same mechanism as squatting...the veins are milking the blood back up to the heart?

[ArchivalUser]

Hand Grip .........Increases the Preload

-it does not significantly increase the venous return to heart .The veins of the arm are not as large as those of legs, so compressing them does not make much difference in venous return to heart.

-increase Afterload----->Increase Aortic Pressure

hence the pressure gradient b/w Aorta and LV decreases.

not letting the LV to pump blood out -

so less blood will be pumped out and more blood will stay in LV causing it to expand--->decreasing the murmur


same mechanism in Aortic Stenosis...

not letting the LV to pump ------hence less Blood will be flowing across Stenosed Aortic valve----> decre in murmur.


source: Dr. Conrad fis.

[ArchivalUser]

correction

Hand grip-----> Increases the "AFTERload"

[ArchivalUser]

.........................Hand grip(inc Afterload)..........Squatting(inc PRE-load)

HOCM murmur---- decrease ...................................decrease

Aortic Stenosis-----decrease ...................................Increase

[ArchivalUser]

okay so I was right the 1st time around, thanks! I read the increased preload thing in Goljan which made me confused.

Sarim..I am confused whether I should re-read Goljan (I read it over a year ago) or just stick with first aid and Goljan audios and uworld?

[ArchivalUser]

stick to what u mentioned and if there is a need u can always peak into Goljan RR.

But frequently look at the slides and side notes.

this murmur thing is explained very nicely in "Master the Boards" by dr. Conrad

[ArchivalUser]

Thanks a lot for ur help Sarim You're awesome!