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  #1  
Old 06-08-2011
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Heart Cardiac pathophysiology question #2

A 75 y/o male presents with acute onset of shortness of breath. On examination you noted an irregular pulse of 120, a blood pressure of 112/87, and a respiratory rate of 25. His jugular veins are distended to an estimated RA pressure of 14 and his carotid upstrokes are delayed. His chest exam reveals dullness to percussion 1/3 the way up bilaterally. His cardiac exam reveals a grade III/VI late peaking systolic ejection murmur with a normal first heart sound and a single second heart sound. His extremities reveal 1+ edema.

1.- Cardiac catheterization of this patient would be likely to reveal all of the following, except:
a) elevation of the pulmonary capillary wedge pressure
b) elevation of the right atrial pressure
c) a significant gradient across the aortic valve
d) a "dip and plateau" in the right ventricular diastolic pressure
e) absence of an oxygen saturation "step-up" between the right atrium and the pulmonary artery

2.- The diagram below shows a normal left ventricular compliance curve, and two additional LV compliance curves. Of the four points shown, which one would be most likely to correspond to this patient at the time of his presentation to the hospital:

Cardiac pathophysiology question #2-plot.gif
click image to enlarge

A) Point A
B) Point B
C) Point C
D) Point D
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  #2  
Old 06-08-2011
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1.. option d
2.. option b
??
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  #3  
Old 06-08-2011
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I am thinking of pulmonary or aortic stenosis..
Single S2 heart sound..may be due to pulmonic stenosis..it can be due to hypertension because A2 is delayed and come close to P2 and we cant distinguish it..well i am weak at pathology
So,considering edema,JVP distension..i can think of pulmonary edema secondary to severe aortic stenosis..
I will go with:
1.E
2.B
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  #4  
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1- Answer (D) This patient has Aortic stenosis (AS) complicated by Acute left ventricular systolic Failure (Acute pulmonary edema) and hence the sysmptoms. By cardiac cathetrization there should be increased left atrial pressure (Reflected as PCWP) due to the increased diastolic pressures caused even earlier in the disease due to decreased compliance and increased stiffness caused by the compansatory left ventricular hypertrophy (Choice A). Also there may be increased right atrial pressure as a part of right sided heart failure caused chronologically after a choronic left ventricular dysfunction that transmitted pressures to the right side, which was confirmed by Jagular viens examination (Choice B). As this patient actually has a complicated symptomatic AS, it is not surprising to have a significant gradient across the valve by either echocardiography or cath. (Choice C). The patient does not show any signs of left to right shunt in the clinical senario or examinations, it is reasonable that O2 step up is absent (Choice E). The only choice that is not reasonable is Choce D (Dip and Plateau) which is characteristic of a different heamodynamic mechanism related to constrictive pathology most commonly seen in constrictive pericrditis.

I have to add that if the patient of AS is in Acute LV failure --> gradient may be lost due to the inability of the ventricle to pump blood and hence loss of systolic pressure

2-I am not quite sure about this one but, (Answer is:B) Compliance is a diastolic function that means dV/dP = changes of diastolic volumes/changes in diastolic pressure and as this patinet's compliance is extremely depressed, it may seem reasonable to choose answer B as the decreased compliance means increased pressure for any given volume and that is not the case except with point B
Point A: decreased both volume and pressure = nearly same compliance
Point C: decreased pressure more than volume = increased compliance
point D: increased pressure and volume = nearly same compliance
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Old 06-08-2011
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I thinks its TS. so C???
and curve C as well ??
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  #6  
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Question

1) d
2) d
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Quote:
Originally Posted by pass7 View Post
I thinks its TS. so C???
and curve C as well ??
Dear Brother
Sure it is not TS for Some reasons

1- Tricupid diseases are charctrised by changes with respiration (Clearly not mentioned in this case)
2- Tricupid valve does not affect the S2 which is made by Aortic and Pulmonary components
3- TS will not cause pulmonary dullness (This is actually caused by left sided problems)
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Quote:
Originally Posted by struggle View Post
I am thinking of pulmonary or aortic stenosis..
Single S2 heart sound..may be due to pulmonic stenosis..it can be due to hypertension because A2 is delayed and come close to P2 and we cant distinguish it..well i am weak at pathology
So,considering edema,JVP distension..i can think of pulmonary edema secondary to severe aortic stenosis..
I will go with:
1.E
2.B
Choice E is wrong brother because the answer said NO STEP UP (so if this was wrong that means there is a step up which means nothing but a left to right shunt e.g. ASD, VSD, PDA ....etc)

Also this cannot be PS because of the pulmonary dullness that is caused by a left sided pathology not a right sided one
Best wishes
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  #9  
Old 06-08-2011
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Correct Answer correct answer

1-D
2-B

Perfect explanation alaahoda2001!
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  #10  
Old 06-08-2011
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wow, great stuff guys!!!
while i got the AS part im not sure i would have been able to get the graph, i was thinking more of point D but what a great explanation! the moment I read the formula, i was like damn! right under our noses...
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  #11  
Old 06-09-2011
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Quote:
Originally Posted by alaahoda2001 View Post
Dear Brother
Sure it is not TS for Some reasons

1- Tricupid diseases are charctrised by changes with respiration (Clearly not mentioned in this case)
2- Tricupid valve does not affect the S2 which is made by Aortic and Pulmonary components
3- TS will not cause pulmonary dullness (This is actually caused by left sided problems)
I meant PS ( i alwys make silly mistakes) for same the reason u mentioned in 2 but then i m still wrong

Thanks a lot for great explanation though!
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Quote:
Originally Posted by pass7 View Post
I meant PS ( i alwys make silly mistakes) for same the reason u mentioned in 2 but then i m still wrong

Thanks a lot for great explanation though!
Dear brother
PS is impossible in this question too
this cannot be PS because of the pulmonary dullness that is caused by a left sided pathology not a right sided one

In right sided lesions the pressure is transmitted backwards to the right side only
If you go back from the pulmonary valve you will find RV --> RA --> IVC or SVC --> SYSTEMIC VIENS
so it is impossible to have lung affection because of PS

on the other hand if you go back from any left sided structure, backward transmission of pressure always involves the lung (in this case: Aortic valve --> LV--> --> LA --> pulmonary VEINS --> pulmonary capillaries --> oozing to alveoli if the capillary pressure is high --> pulmonary edema

BEST WISHES

Best wishes
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  #13  
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tough question
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  #14  
Old 06-09-2011
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Quote:
Originally Posted by alaahoda2001 View Post
Dear brother
PS is impossible in this question too
this cannot be PS because of the pulmonary dullness that is caused by a left sided pathology not a right sided one

In right sided lesions the pressure is transmitted backwards to the right side only
If you go back from the pulmonary valve you will find RV --> RA --> IVC or SVC --> SYSTEMIC VIENS
so it is impossible to have lung affection because of PS

on the other hand if you go back from any left sided structure, backward transmission of pressure always involves the lung (in this case: Aortic valve --> LV--> --> LA --> pulmonary VEINS --> pulmonary capillaries --> oozing to alveoli if the capillary pressure is high --> pulmonary edema

BEST WISHES

Best wishes
Hiii
thanks again! just a minor problem though, i thought i wouldnt say this but since u called me the "brother" the second time ,it sounds bit funny, since i m not a guy!!
anyway thanks fr the correction and best wishes for u too
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