Step I Nitrates effect on ESV

[aspiringmd1015]

nitrates effect on ESV? it decreases EDV bc of decreasing preload, but it also lowers afterload, so it should be associated with no effect on ESV no? and in any case contractlitiy is not increasing, but apprarently with nitrates you get a decreased ESV.

 

[link2swim06]

Think about what you just said. Less preload so less blood returning to the heart. Less afterload so less resistance for the blood to leave the heart. Less blood in the heart all together.

Nitrates themselves don't increase stroke volume but they manipulate the positioning on the frank starling curve and can improve contractility if the patient is volume overloaded.

 

[aspiringmd1015]

my issue is that, i had the concept that contractility is 1/x to ESV, the patients contractility shouldnt be increasing, the only thing that could increase is SV, contractility is dependent on the amount of Ca2+, for example, giving an inotrope compared to exercise, an inotrope decreases your ESV, whereas excercise doesnt. but what youre saying makes complete sense lol, my bad, i guess over thought that one