physio q

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physio q

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8 Posts

shalu
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Posts: 56

11/16/05 - 06:53 PM

2.A 72 yr old woman comes to the physician bcaz of a episode of acute substernal chest pain that occured while she was rushing to catch a bus. She has basilar crackles at both lung bases. S1 is sormal and S2 is decreased. A grade 3/6 systolic murmur is heard best at the upper right sternal border and radiates to the neck. The foll data obtained during cardiac catheterization were taken before and during exercise: Left ventricular volume
Aortic Pressure end-diastolic end-systolic Heart rate
mm Hg mL mL /min
Control 130/70 140 50 85
Exercise 160/80 165 58 120 While exercising the patient has shortness of breath but no chest pain. Which of the foll is the most likely cause of the shortness of breath?
A. Decreased cardiac output during exercise
B. Decreased pulmonary blood flow
C. Increased aortic pressure
D. Increased end-diastolic pressure of the left ventricle during exercise
E. Tachycardia

sturge_weber
Forum Guru

Topics: 77
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11/16/05 - 07:24 PM

can u please explain what these no.s stand for ie control and exercise, can u please rewrite

cant get that

but what i can make out without the values is she has aortic stenosis, and so the end diastolic pressure has increased as the heart cant pump out thro the stenotic valve , hence leading to back pressure and pulmonary edema

but please write the values again

cyra
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11/16/05 - 07:26 PM

I think its D.

Sturge...you are right...it is aortic stenosis...there would be an increase in end systolic volume due to a decrease in stroke volume b/c of the stenosis.This would lead to a compensatory increase in end diastolic volume and pressure.I was a bit inclined toward A but then that does not explain the shortness of breath..

also.....correct me if i am wrong...if there is aortic stenosis...it does cause a decrease in cardiac output...wouldn't it also impede coronary blood flow and cause chest pain??...if they question had asked about the cause of chest pain...it would have been choice A..right?

Edited by cyra on 11/16/05 - 07:38 PM

sturge_weber
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11/16/05 - 07:30 PM

hey cyra can u explain those values

sturge_weber
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11/16/05 - 07:31 PM

i think its d

cyra
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11/16/05 - 07:48 PM

sure.....the two sets are taken with the patient at rest...the control...and the other set is during exercise...

LV volume Aortic P EDV ESV HR

Control 130 70 140 50 85

Exercise 160 80 165 58 120

These values indicate an aortic stenosis...note the ESV increase during exercise.There is also an increse in the EDV during exercise which i'd think is cos of the increased ESV due to the stenosis.

i also just noticed that cardiac output is actaully incresing during exercise....the stroke volume is increasing during exercise and so is the heart rate...so option A is ruled out...

Edited by cyra on 11/16/05 - 08:07 PM

cyra
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11/16/05 - 07:50 PM

arrrrrrgh...this thing messed up...i hope you can figure out the values...they were fine when i was typing... confused

...you'll have to match them youself i guess...hope it makes some sense!

sturge_weber
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11/16/05 - 08:20 PM

ya u re right cyra

when there is aortic cyanosi, the stroke volume would decrease , hence the end diastolic volume would increase, hence more blood in the ventricle, ultimately the heart will start failing and the backpressure to the lungs, leading to pulmonary edema

4 ur second doubt cyra, the heart would spend more time in systole, trying to pump out blood, this means less time in diastole, hence coronaries would not fill. hence chest pain

but the decreased cardiac output would lead to fainting spells, and not to pulmonary edema

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