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Discussion Starter · #1 ·
A 54-year-old woman presents with a pansystolic murmur along the lower left sternal border radiating rightward to the midclavicular line. The murmur is medium pitched, has a blowing quality, and increases slightly on inspiration. An S3 is audible along the lower left sternal border. Jugular venous pressure is elevated, and a prominent "v" wave is visible. Which of the following is the most likely etiology of the S3?


A. Aortic stenosis
B. Mitral regurgitation
C. Pulmonic stenosis
D. Tricuspid regurgitation
E. Volume overloaded left ventricle
F. Volume overloaded right ventricle
 

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i think overloaded right ventricle.

im stuck between B, D and F. :p (too many choices i know but i can't seem to put my mind on any one of them answers).

but if i were to go on the basis of the sound heard at the lower left sternal border, then its either D or F. but since there is an S3 sound (which indicates overloaded heart or CHF), then its either E or F).

so now to break it down more, the S3 sound was better heard during inspiration & at the lower left sternal border which indicates right-sided overload (thats my final answer) if the question said that the S3 sound was heard best at the midclavicular ICS5 and higher intensity during expiration, then i would pick overloaded left ventricle.

sigh... am i making any sense? more importantly, did i pick the right answer?:p
 

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oh and to add, her JVD indicates right sided heart failure!! :D (i guess this would mean that im completely eliminating my first B choice and guessing between tricuspid regurgitation & overload right ventr. but with the S3, again, Im going with overload right ventr. as my final answer!!:cool:
 

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thank u dr. sam for sharing the question.

ps: pls share more questions if u have any. is it just me or have the question sharing decreased this month? i don't seem to see many questions to read this month on this forum. i have a few that i want to share. perhaps this sat when i get the time.;)
 

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Hey, Dr. Seetal, you are right! The question load has fallen dramatically! C'mon guys, let's go back to some constructive medical debate!!! :))
 

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Most probably it's F, Dr. Seetal must be right. Let's see why...

The findings from auscultation are actually suggestive of tricuspid regurgitation. It's the only holosystolic murmur that is better audible on inspiration; VSD and mitral regurgitation, instead, are equally audible on inspiration and expiration. This happens because the wall of the right ventricle is almost 1/3 the thickness of the left ventricle and thus is more affected by the changes in mediastinal pressure. Given that the volume and the pressure of the mediastinum increase on inspiration, RV is more "collapsed" and consequently the regurgitant blood volume to the right atrium is greater => regurgitation murmur is harder. What is more, the gender of this patient is compatible with idiopathic pulmonary hypertension, which may account as a reason for her tricuspid insufficiency and subsequent regurgitation.

However Dr. Seetal has correctly underlined that the S3 is suggestive of the development of heart failure, i.e. right ventricular failure secondary to tricuspid regurgitation. Volume overload is the culprit underlying this failure.
 

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F??

ya u r right....was bit confused with prominant v wave...
they asked us the reason for S3...n its a volume overloaded rt. ventricle...
 

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Discussion Starter · #9 ·
The correct answer

u re so smart guys.
Yes The correct answer is F. The origin and radiation of the pansystolic murmur suggest tricuspid valve incompetence. This is further supported by its pitch and quality, and by the fact that it increases on inspiration when cardiac volume increases. The regurgitant blood flow from the ventricle during systole increases jugular venous blood pressure and atrial v wave amplitude. The origin of the S3 sound, which occurs during early rapidfilling, is the filling of a volume-overloaded right ventricle. The right ventricle overload is caused by the combination of systemic venous return and the return of the regurgitated blood volume into the right ventricle.Right ventricular failure and dilatation, with enlargement of the tricuspid valve orifice, is the most common cause of tricuspid regurgitation and is often secondary to pulmonary hypertension or left ventricular failure
 
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