HOCM and Aortic Stenosis

Basic concepts regarding HOCM and aortic stenosis with high yield topics for the Board Exams.

[@knightcardio7387]

Promptly standing up from the squatting position results in sudden pooling of blood in the legs, decreasing venous return (preload) with an increase in the LVOT obstruction and hence an increase in the HOCM murmur.

[@rcstwin]

Hello! Thank you so much for this very helpful and clear video! My only question is regarding the BMB charts- my understanding of what you said is that after the PVC we have increased LV filling and that causes increased pressure/ force of contraction (Frank Starling Law) leading to more obstruction in HOCM. But isn't the treatment of HOCM also geared at increasing LV volume to decrease obstruction? These seem like opposite results of the same mechanism. I would definitely appreciate some clarification if you have time.

[@Harmoniou-s]

I am a little confused on why this video was recommended to me. I wanted memes and j got knowledge. Thank you anyways!

[@mahnoormahnoor3013]

Can u plz explain about the Normal and abnormal pressure waves(like in stenosis and regurgitation process) with their pressure values

[@Sickdude420]

Nice video but can you explain one thing. You said that increased preload/blood flow to the LV will lead to the LVOT obstruction in HOCM to be less as their is more blood between the septum and the MV. And anything that reduced blood flow to the LV in HOCM will lead to a louder murmur because there is more obstruction of the LVOT as there is less blood sitting between the outflow tract. However in the case of the PVC leading to a compensatory pause, leading to more LV filling, wouldn't this actually create a good situation in HOCM as now the LV if filled more and stretched out and the septum is less likely to collapse in and block outflow? or is it that this increased filling produced such a large contraction due to frank staling law that is overcomes the benefit of increased preload leading to LVOT obstruction. It seemed a bit contradictory but it is right I agree but just not sure what the explanation would be.

[@whiteboardandmarkercardiol2787]

Thanks. You are right, PVC will increase the filling because of the compensatory pause and the murmur and obstruction will go down because of dys-synchrony. Post PVC then the filing be low and increased obstruction In the past, this physiology was utilized in patient with severe HOCM for their benefit. They would get pacemakers that would pace the RV leading to Left bundle morphology and dyssynchrony. We dont do this anymore. Hope this helps

[@Sickdude420]

@@whiteboardandmarkercardiol2787 ahhhhhh thanks so much, yes so its the beat after that is under-filed and thus results in LVOT obstruction resulting in the increase in the LV / AO gradient, awesome thanks soo much ! awesome video by the way keep it up please

[@mahvishbukhari6234]

Think the same

[@mohamealemam9969]

Excellent

[@whiteboardandmarkercardiol2787]

Thanks for watching…