Myocardial Blood Flow - Coronary vessels

During contraction of the ventricular myocardium (systole), the subendocardial coronary vessels (the vessels that enter the myocardium) are compressed due to the high intraventricular pressures. However, the epicardial coronary vessels (the vessels that run along the outer surface of the heart) remain patent. Because of this, blood flow in the subendocardium stops. As a result most myocardial perfusion occurs during heart relaxation (diastole) when the subendocardial coronary vessels are patent and under low pressure. This contributes to the filling difficulties of the coronary arteries. Compression remains the same. Failure of oxygen delivery caused by a decrease in blood flow in front of increased oxygen demand of the heart results in tissue ischemia, a condition of oxygen debt. Brief ischemia is associated with intense chest pain, known as angina. Severe ischemia can cause the heart muscle to die from hypoxia, such as during a myocardial infarction. Chronic moderate ischemia causes contraction of the heart to weaken, known as myocardial hibernation.

Category:

Education

Tags:

• myocardial
• blood
• flow
• coronary
• arteries
• vessels
• ventricles
• heart
• systole
• cardiac
• pressure
• diastole
• oxygen
• tissue
• prefusion
• ischemia
• video

[mido92ful]

I want to ask a question about the amount of oxygen consumption

I've red that the heart consume 100% of coronary blood & the blood become fully deoxygenated

which one is correct?

plz. answer

[jhoenedu]

I am very happy to see the vidoe from you, hopefully the others also are happy for You Chronic moderate ischemia causes contraction of the heart to weaken, known as myocardial hibernation.

[echocardiographie]

nice

[TheKcsmithy]

some great inforamtion here thanks

[grisgrisy]

some sweet info here

[msjessypp]

interesting video and very informative

[Resoses]

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[simysimss]

very interesting video thanks

[MelnDyl2010]

Now in my bookmarks bar favourite on youtube and now u have just earned a subscription

[TheMunii]

thank you so much.