NB F2- Q4 Cardio

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NB F2- Q4 Cardio

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Musuq
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09/21/06 - 11:04 AM

A 63-year-old woman has chest pain while climbing the stairs of her office building. She sits down and takes some medication, after which she is able to continue. Which of the following is the mechanism of action of the drug?

A) Decreased afterload

B) Decreased preload

C) Increased afterload and preload

D) Increased preload

E) Increased contractility

drfax
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09/21/06 - 11:26 AM

B.decrease preload
coz nitrogylcerin which this patient taking for her angina make her arteries and viens to dilate and therefore decrease venous return (so preload)
it also decreases afterload which is choice A ????!!!!!!!! how that will be

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dr.mum
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09/22/06 - 08:28 PM

A

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docswapna
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09/22/06 - 09:06 PM

better to take B as the ans bcos decreased after load usually causes syncope which is not presen here.

young_doc
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09/22/06 - 10:25 PM

drfax wrote:
B.decrease preload
coz nitrogylcerin which this patient taking for her angina make her arteries and viens to dilate and therefore decrease venous return (so preload)
it also decreases afterload which is choice A ????!!!!!!!! how that will be

Nitroglycerin works mainly on VEINS. So will not greatly affect Afterload.

(Its main mechanism of action, like you mentioned, is by decreasing venous return, hence decreased preload).

B.

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klimt
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10/15/06 - 02:24 PM

B
young_doc is right. NTG acts only on veins, dilates them so it decreases preload

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ManuNastai
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10/16/06 - 10:31 AM

agree B

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tran6996
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10/16/06 - 12:46 PM

basically..pt is using NITRATE...
and it work on preload(decrease)

so answer is B

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