Coronary Circulation

Question 1

Where do the left and right coronary arteries originate from?

Answer 1

They originate from the left & right aortic sinuses

Question 2

Answer 2

Question 3

Branches of the Right Coronary Artery? (4)

Answer 3

–Branch to SA node

–Right (acute) marginal (does not reach apex)

–Posterior descending artery (PDA) (also called posterior interventricular branch)

–Branch to AV node (at crux of heart)

Question 4

Define Coronary Dominance

Answer 4

If the right coronary artery gives off the posterior interventricular branch (aka PDA) (which perfuses the posterior region of the ventricular septum and the posterolateral aspect of the left ventricle), then the heart would be described as being right dominant; the converse is also true.

In the majority of cases, the right coronary is the dominant artery; however, both left dominance and codominance (equal supply from both coronary arteries) have been observed.

Question 5

Left or Right Dominant?

Answer 5

LEFT Dominant

Question 6

Left or Right Dominant?

Answer 6

RIGHT Dominant

Question 7

What does the Right Coronary Artery Supply?

Answer 7

–Right atrium

–Most of right ventricle

–Part of the left ventricle (diaphragmatic surface)

–Part of IV septum (posterior 1/3)

–SA node (60%)

–AV node (80%)

Question 8

What supplies the Interventricular Septum

Answer 8

• RCA –posterior one third
• LCA –anterior two thirds

Question 9

Branches of the Left Coronary Artery and what they give rise to

Answer 9

Two major branches:

–Anterior interventricular branch (or LAD) → Diagonal Arteries

–Circumflex (Cx) branch → left (obtuse) marginal branches

Question 10

What does the left coronary artery supply?

Answer 10

Typically, the left coronary artery supplies:

–Left atrium

–Most of left ventricle

–Part of the right ventricle

–Most of the IV septum (anterior 2/3, inc. AV bundle)

–[SA node (40%)]

–[AV node (20%)]

Question 11

There are no __________ between larger coronary vessels

Answer 11

There are no major anastomoses between larger coronary vessels

Some collaterals exist among smaller branches, w/ potential for further development in cases of chronic arterial occlusion

Question 12

________________ is the major venous drainage vessel of the heart

Answer 12

Coronary sinus is the major venous drainage vessel of the heart

Question 13

Where is the Coronary Sinus located and to where does it drain?

Answer 13

• Situated in the posterior coronary sulcus
• Drains to the right atrium

Question 14

The coronary sinus receives four major tributaries:

Answer 14

Question 15

What is the leading cause of death worldwide?

Answer 15

Coronary Artery Disease

Question 16

b

______________: involves manually widening narrowed or obstructed arteries

Answer 16

Angioplasty: involves manually widening narrowed or obstructed arteries

Balloon catheter placed in artery over guide wire using minimally invasive surgery (percutaneous coronary intervention, PCI)

Expanded to compress plaque and withdrawn

Question 17

______________

–Balloon catheter placed in artery over guide wire using minimally invasive surgery (percutaneous coronary intervention, PCI)

–Stent crimped onto balloon expands during deployment to keep lumen open

–Restenosis can occur, however (foreign body response)

Answer 17

Stenting

–Balloon catheter placed in artery over guide wire using minimally invasive surgery (percutaneous coronary intervention, PCI)

–Stent crimped onto balloon expands during deployment to keep lumen open

–Restenosis can occur, however (foreign body response)

Question 18

What is the threshold at which coronary bypass surgery is needed?

Answer 18

Occlusion of >70% generally requires bypass grafting to the re-vascularize the affected area

Question 19

Most common sites of coronary artery occlusion?

Answer 19

Most Common Sites of Occlusion

• Anterior Interventricular (LAD branch) of LCA (40-50%) (‘_widowmaker_’)
• RCA (30-40%)
• Circumflex branch of LCA (15-20%)