Lecture 2: The Heart Flashcards
(84 cards)
Why is it important to have myocardium attached to the skeleton of the heart?
Prevents it from overexpanding and helps return to its normal shape after contraction
List some functions of the skeleton of the heart.
- It electrically separates the atria from the ventricle.
-helps return heart back to normal size and shape after contraction
-physical support for cardiac muscle
-prevents overexpansion of heart
-fibrous structure
When all four chambers of the heart contracts at once, it doesn’t work well. Why?
If the ventricles contract while the atria contracts, there’s no place to put the blood. When the atria sits on top of the skeleton of the heart, and ventricles are below it, the electrical signal being shared in the atria can’t get pass through into the ventricles.
What are valves?
They are the entrance and exit to ventricles
What are atrias?
They are receiving channels with thin myocardium
How do ventricles contribute in the heart?
The power of pump. Pressure is so much higher than atrium.
Trace the pathway of blood flow through the heart starting from the Inferior Vena Cava and end in the Aorta.
IVC > RA > TV > RV > Pulmonary Valve > PT > PA / Lungs > Pulmonary Veins > LA > MV / BV > LV > AV > Aorta
What is coronary circulation?
The blood vessels that are giving blood to the myocardium.
What are the first two branches off of the aorta?
The left coronary artery and right coronary artery
When the aortic valve is open ( blood flows from LV to Aorta) , what happens?
The flaps of the aortic valve covers the openings to the R and L coronary arteries.
Why do you cover the coronary arteries?
It closes the blood vessel not letting blood get in. Blood goes pass the openings to the R & L coronary arteries
Explain the physiological process of how the blood goes passed the openings to the R & L coronary arteries.
When ventricles contract and blood is getting pumped out into the aorta, we cover the openings. When ventricles start to relax, the pressure starts to drop and won’t be high. The valve closes so it won’t go back into the ventricle. The blood hits the valve flaps and gets directed straight into the R & L coronary arteries.
The Left coronary artery branches into what?
Anterior ventricular artery ( runs into the Anterior interventricular sulcus) and Circumflex Artery ( runs around to backside of heart)
The Right coronary artery branches into what?
Marginal artery and Posterior interventricular artery ( runs into the posterior interventricular sulcus)
What do the Left and Right Coronary arteries do?
Provide blood to the myocardium of both ventricles.
Why is it important that the L & R coronary arteries provide blood to the myocardium of BOTH ventricles?
When one gets blocked, you still have at least still some blood flow from the coronary artery.
Atria only get blood supply from the coronary artery on THEIR side. What does this mean?
R coronary artery provide blood to the myocardium of the R Atrium.
L coronary artery provide blood to the myocardium of the L atrium.
Anterior interventricular arteries have two names. What is it?
Left anterior descending artery
& Widowmaker ( slang)
What’s the most common place for blockage for a fatal heart attack?
Anterior interventricular arteries ( Left Anterior Descending Artery) because it supplies MOST of the blood to the left ventricular myocardium. This is the most effective by a decrease in O2 bc more muscle needs more O2.
What ventricle gets the most blood?
Left Ventricle because it does the most work. It needs the most O2 and glucose.
As an energy source, what does your heart work with?
Fatty acids and glucose
What is Anastamosis?
Blood vessels connect to each other WITHOUT any capillaries in between.
Where the Anterior ventricular artery runs into branches of the marginal artery.
How does Anastamosis affect myocardium?
It can be a way to bypass smaller blockage
What can induce development of Anastamosis?
Low O2 levels in region of myocardium. BUT is way too long to do much good.
