Lecture 7 - Coronary circulation & conduction systems

Question 1

The right and left coronary originate from…

Answer 1

ascending aorta - just above the aortic semilunar valve

Question 2

Where does the Right coronary artery run?

Answer 2

in the right aV groove - wraps around posteriorly

Question 3

What branches does the Right coronary artery give off?

Answer 3

porterior IV branch

and

marginal artery

and

very small arteries going to the atrium - SA nodal branch, posteriorly AV nodal branch

Question 4

Where does the Left coronary artery run?

Answer 4

postgerior to the pulmonary trunk - as it goes lateral we can see it in the left AV groove.
As soon as it gets past the trunk it divides into the circumflex (in AV groove) and ant. IV branch.

Question 5

What are the Left coronary a. divisions?

Answer 5

As soon as it gets past the trunk it divides into the circumflex (in AV groove) and ant. IV branch.

there is a marginal branch that comes off the circumflex

Question 6

Depending on which coronary artery the ____ _-_branch comes off determines whether the left or right is the dominant

Answer 6

Depending on which coronary artery the posterior IV branch comes off determines whether the left or right is the dominant

Question 7

Which coronary supplies the SA and AV node?

Answer 7

Right coronary

but not always

Question 8

Generally speaking Left coronary does which chambers?

Answer 8

left atrium and most of left ventricle (doesn’t do diaphragmatic part)

Question 9

True or False

are the coronaries anatomical end arteries?

Answer 9

False

They are function end arterioes - anatastomose in 2 places

if there is a slow occlusion, they open up and communicate

Question 10

Where do the coronaries anastomose?

Answer 10

1 – just behind the apex - the IV arteries

2 - on the posterior surface where the circumflexes meet

Question 11

Coronary heart disease casues tissue diease which causes the release of _______ ________ which stimulate pain and cause ineffective blood pumping

Answer 11

Coronary heart disease casues tissue diease which causes the release of inflammatory mediatores which stimulate pain and cause ineffective blood pumping

Question 12

Angiography involves ____ with contrast injected

Answer 12

X-ray

Question 13

What is Angioplasty?

Answer 13

Inserting an inflatable balloon which aims to open to the artery. If there is a chance it will open again a stent is used it keep it open?

Question 14

If openings are so blocked up, and can;t be opened, a bypass surgery is required, what does this involve?

Answer 14

Taking a vein (ususally) and putting it from aorta to spot distal from blockage - saphenous vein, int. mammary art., radial art. commonly used

Question 15

Where does the coronary sinus sit?

Answer 15

in the posterior AV groove

Question 16

Which vein runs wit the ant IV artery?

Answer 16

Great cardiac vein - as we come posterior becomes middle cardiac vein

Question 17

Which vein runs in the posterior IV groove?

Answer 17

middle cardiac vein

Question 18

Which vein runs iwth the right marginal artery?

Answer 18

Small cardiac vein

Question 19

Which vein drains the left atrium?

Answer 19

oblique vein

Question 20

Where does the AV node sit?

Answer 20

lower part of the right atria

It is located at the center of Koch’s Triangle—a triangle enclosed by the septal leaflet of the tricuspid valve, the coronary sinus, and the membraneous part of the interatrial septum

Question 21

From the AV bndle (bundle of His) what comes off?

Answer 21

Left bundle branch
- goes to left ventricle

Right bundle branch

• (from this theres the moderator band)
• The right bundle moves through the exagerrated papillary muscle
• The bundle splits up inferiorly and arch back up to innervate the ventricles

Question 22

Will the AV node produce pulses in the absense of the SA node?

Answer 22

yes - it is usually the dominant pacemaker

Question 23

Where does the SA node sit?

Answer 23

Anterior surface of the RA just beneath the SVC

Question 24

Which node is the intrinsic node?

Answer 24

SA node - even without any input will beat about 70 bpm

Question 25

Damage to the SA node can be compensated for by the ___ node’s intrinsic action - we can survive in this state

Answer 25

Damage to the SA node can be compensated for by the AV node’s intrinsic action - we can survive in this state

Question 26

What happens if AV node is stopped?

Answer 26

big problem, no impulses carried to the ventricles = heart block

• SA activity can no longer reach the ventricles

Question 27

What is the path of a pacemaker?

Answer 27

Subclavian vein SVC - RA - into ventricles

• stimulation passes directly into the ventricle