@dramitk57 ~~~ - sarim

[ArchivalUser]

http://www.usmleforum.com/showthread.php?tid=647755


Hi

In reference to above post, I think we got a misunderstanding here.


When i said that
"O2 extraction from coronary blood by myocytes is at it's MAX(100% or near 100%) at rest"

% here is in regards to the "Capacity Of O2 Extraction" and NOT referring to the % of O2 extracted from the coronary blood which is as u mentioned 70 - 80%


e.g.

If there is 100% O2 in Coronary ARTERIAL Blood---- 80% Extracted by Myocytes----> 20% O2 left in the Coronary VENOUS Blood.

Now that 80% extracted is the "MAX Capacity Of O2 Extraction"(100% Capacity of extraction).

*Since Heart extract O2 at it's MAX Capacity at rest..... During Increased Metabolic Demand, the ONLY way we can provide more O2 is by increasing the Blood Flow.

Thanks.

[ArchivalUser]

.....

[ArchivalUser]

thanks ......sarim..........
i got the point.

[ArchivalUser]

Cool