[drmodi44]

can anyone pls explain wt is difference between compensated n un compensated coarctation of aorta...n also wt is difference bet blood flow,blood pressure n peripheral vascular resistance....in upper n lower body segment in both of this condition....

 

[drmodi44]

Hi,

I myself have no grasp on this topic....

But have a look at these links .....

http://www.medscape.com/viewarticle/703899_4

http://emedicine.medscape.com/article/895502-overview

http://www.wikidoc.org/index.php/Aortic_coarctation

These may be of some help.........

hey thanks for reply....but i didnt find anything regarding compensated or uncompensated things....i saw only superficially though....
i came across 2 Qs in kaplan about the same thing n i was hardly able to understand wt they were trying to explain....
main thing m not getting is peripheral vascular resistance....
in compensated heart failure blood flow is equal in both upper n lower body parts...
P=QR so now we only hv to correlate between P n R....but they also mentioned characteristic pulse...like brisk or bounding..or wt ever....i dont remember much...
n we hv to answer from that whether PVR is raised or low.....

 

[step1an]

Plz correct me if i am wrong.... My understanding is that in the segment before the CoA there is hypertension & decreased PVR.
And in the segment distal to CoA, PVR should increase to compensate for decreasing blood pressure.

 

[drmodi44]

my understanding is different though....
compensated COA blood flow is equal in both upper n lower segment....
n blood pressure is already high in upper segment due to renin angiotensin system...so...if we go with P=QR.....
R=P/Q..
R is proportional to P....means there should be high resistance in upper part...in compensated....
but in uncompensated....Q is low in lower body....so according to R=P/Q....resistance will be high in lower body......but pressure is also low.....so cant say exactly....
actually they give us clue by giving characteristic of pulse...
like if pulse in upper part is brisk then there must be low resistance....
ughhhh......!! m getting more n more confused.....
i'll post that 2 Qs if i find them....

 

[dranant]

Better you post them.............I WOULD LIKE TO ANSWER.

my understanding is different though....
compensated COA blood flow is equal in both upper n lower segment....
n blood pressure is already high in upper segment due to renin angiotensin system...so...if we go with P=QR.....
R=P/Q..
R is proportional to P....means there should be high resistance in upper part...in compensated....
but in uncompensated....Q is low in lower body....so according to R=P/Q....resistance will be high in lower body......but pressure is also low.....so cant say exactly....
actually they give us clue by giving characteristic of pulse...
like if pulse in upper part is brisk then there must be low resistance....
ughhhh......!! m getting more n more confused.....
i'll post that 2 Qs if i find them....

post those 2 questions,I would like to answer.......................

 

[drmodi44]

post those 2 questions,I would like to answer.......................

http://www.usmle-forums.com/usmle-step-1-forum/3867-coa.html