mitral Regurg and increased contractility

[aspiringmd1015]

WHy does increasing the contractility in patients with Mitral regurg lead to an increase in afterload?

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[Phloston]

WHy does increasing the contractility in patients with Mitral regurg lead to an increase in afterload?

Regurg should increase preload. Only way would be secondary hypertrophic changes leading to left ventricular stiffening, which would theoretically present an increased afterload against the left atrium. But regurg would directly cause an increased preload.

 

[aspiringmd1015]

right, the explanatoin stated that giving inotropes to a patient with mitral regurg isnt favorable, bc it will lead to increased afterload

 

[TBV]

What was the inotrope If it was dobutamine or something it could be getting at vascular effects and want you to know that in regurg you want less afterload

 

[worldbeater]

right, the explanatoin stated that giving inotropes to a patient with mitral regurg isnt favorable, bc it will lead to increased afterload

That's your answer right there. Normal physio says in MR you will have a decreased afterload (blood squirting back up) and increased preload (due to more blood in the left atrium from the last contraction). To make the condition better and reduce the regurgitation, you are trying to minimize the afterload.

You said inotropes aren't favorable, so that's why you have a worse problem, or increased afterload.

I talk about MR in a previous thread:

http://forums.studentdoctor.net/threads/mitral-regurge.1186911/#post-17501178

"To understand preload, lets talk about the afterload first, which this question is hitting at. Afterload is the amount of blood present in the ventricle after ejection. In a case of mitral regurgitation (the differential you come to with the description in the stem), your having a problem during systole (during ejection), where blood is squirting back from left ventricle to the left atrium. The normal physiology in systole is the mitral valve is closed and the aortic valve is open to squeeze blood into the aorta and deliver it to the arterial system. But that's not the case here, it's going in the wrong direction. So to minimize the amount of blood that squirts backwards, we would want to decrease the afterload."