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cardiac

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14 Posts

docsrinu
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Topics: 26
Posts: 213

09/13/06 - 09:31 PM

A 65 years old man came to physician due to an episode of acute substernal chest pain that occurred while he was rushing to catch a train. He has basilar crackles at both lung bases.S1 is nomal and S2 is decreased.A grade 3/6 systolic murmer is heard best at the upper right sternal border and radiates to the neck.the following data obtained during cardic catheterization were taken before and during excercise:
aortic pressure EDV ESV HR
control 130/70 140 50 85
excercise 160/80 165 58 120
While excersicing the man developed shortness of breath but no chest pain.Which of the following is the most likely cause of shortness of breath?
A tachycardia
B decrease the pulmonary blood flow
C increase aortic pressure
D increased end- diastolic pressure of LV during exercise
E decreased cardiac output during exercise

vanshita
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09/13/06 - 09:50 PM

Addicudo
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12/28/06 - 11:33 PM

Cardiac output in this pt. (from his Control settings to his excercise settings) .. Is Increasing .. via .. EDV-ESV = Stroke output X Heart rate .. Both SV and HR are increasing in excercise .. I would go for option B) May be pt has pulmonary stenosis .. and in the excercise settings .. he needs omre Oxygen .. and therefore stenosis leads to Shortness .. and not Chest pain .. ! Comments to correct me would be appreciated .. ! wink

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Ancylostoma
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12/29/06 - 01:14 AM

the answer is D, he has a systolic murmur that radiates in to the neck, best heard over the right sternal border. The increase in preload caused by the stenosis leads to the in hydrostatic pressure in the pulmonary vasculature . This leads to pulmonary edema and he has difficulty breathing and basilar crackles.

johnnyu041
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12/29/06 - 05:30 AM

I agree with ancylostoma...the most important thing is the increase in EDV during exercise which causes congestion of the pulmonary vasculature which leads to the shortness of breath...its probably due to the aortic stenosis causing an outflow obstruction when the cardiac output needs to increase i.e. during exercise

Ancylostoma
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12/29/06 - 07:41 PM

I forgot to write that the man had aortic stenosis, that what I thought I put instead of systolic mumur. Looks like johnny corrected me.

Edited by Ancylostoma on 12/29/06 - 07:47 PM

me007
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01/02/07 - 07:24 PM

Cardiac output after exercise is increased in this patient
In aortic stenosis we have decreased cardiac output.
Could anybody explain this?

me007
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01/02/07 - 07:34 PM

Normal CO is 5-6 liters per minute

In this patient before exercise CO=(EDV-ESV)xHR =(140-90)x 85 = 7650 - means increased even before exercise
After exercise CO=(165-58)x120=12840.
12 liters
How it can happens in aortic stenosis???

Otherwise everithing fits in aortic stenosis - auscultation, LHF, pulm edema.

Luckyall
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01/10/07 - 05:16 PM

totally D)

laura81
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Topics: 32
Posts: 176

02/17/07 - 04:24 PM

#10

its a trciky question cause in ao stenosis it supposed to be a increased
pressure gradiant across the ao valve...

babydoc4usmle
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02/18/07 - 08:34 AM

#11

it is aortic stenosis, everybody agrees
EF stays the same in increased CO --> pulmonary congestion increases --> decrease pulmonary blood flow --> pulmonary edema --> shortenss of breath
what about answer B?

usmle4me
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02/18/07 - 09:55 AM

#12

babydoc4usmle
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02/18/07 - 12:30 PM

#13

CO during exercise is UP, not decreased

pasteur000
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02/22/07 - 12:08 PM

#14

The increased CO explains why he doesn't have chest pain now during exercise but why did he experience chest pain at the train?

The answer is D for SOB but the clinical picture suits AS everywhere except the increased CO. Are you all sure if we can use the CO= (HDV-...) forumula here?

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