coronary circulation

Question 1

coronary arteries

Answer 1

left and right

arise from left and right aortic sinuses within aorta

Question 2

aortic sinuses

Answer 2

small openings within aorta behind left and right flaps of aortic valve

when heart is relaxed, back flow of blood fills valve pockets - blood enters coronary arteries

Question 3

left coronary artery

Answer 3

LCA
branches into left anterior descending/anterior interventricular artery
left marginal artery and left circumflex artery (left posterior surface)
~20-25% of individuals - LCX contributes to posterior interventricular artery

Question 4

right coronary artery

Answer 4

branches to form right marginal artery anteriorly

~80-85% individuals - branches into posterior interventricular artery posteriorly

Question 5

cardiac veins

Answer 5

blood travels from subendocardium into thebesian veins

Question 6

thebesian veins

Answer 6

small tributaries running through myocardium - drain into larger veins emptying into coronary sinus

Question 7

coronary sinus

Answer 7

main vein of heart

posterior surface in coronary sulcus (running between left atrium and ventricle)

Question 8

sinus drainage

Answer 8

into right atrium

opening of coronary sinus is between right AV orifice and IVC orificed

Question 9

five tributaries draining into coronary sinus

Answer 9

great cardiac vein
small cardiac vein 
middle cardiac vein
left marginal vein
left posterior ventricular vein

Question 10

great cardiac vein

Answer 10

originates at apex, follows anterior interventricular groove into coronary sulcus, around left heart to join coronary sinus

Question 11

small cardiac vein

Answer 11

anterior surface

passes around right side of heart to join coronary sinus

Question 12

middle cardiac vein

Answer 12

posterior surface of heart

Question 13

left marginal vein

Answer 13

left posterior side

Question 14

left posterior ventricular vein

Answer 14

centre - runs along posterior interventricular sulcus to join coronary sinus

Question 15

RCA

Answer 15

passes to right of pulmonary trunk

runs along coronary sulcus before branching

Question 16

right marginal artery

Answer 16

arises from RCA, moves along right and inferior border of the heart towards apex

Question 17

posterior RCA

Answer 17

continues to posterior surface, along coronary sulcus - posterior interventricular artery arises from RCA, follows posterior interventricular groove towards apex

Question 18

LCA

Answer 18

passes between left side of pulmonary trunk and left auricle

divides into anterior interventricular branch (LAD) and circumflex branch

Question 19

LAD

Answer 19

follows anterior interventricular groove towards apex, continues on posterior surface to anastomose with posterior interventricular branch

Question 20

LCX

Answer 20

follows coronary sulcus to left border and onto posterior surface - left marginal branch, follows left border

Question 21

RCA supply

Answer 21

supplies RA and RV
SA and AV nodes
posterior part of IVS

Question 22

RMA supply

Answer 22

supplies RV and apex

Question 23

LAD supply

Answer 23

supplies RV, LV and anterior 2/3 interventricular septum

Question 24

LMA supply

Answer 24

supplies LV

Question 25

LCX supply

Answer 25

supplies LA and LV

Question 26

PIa supply

Answer 26

RV and LV, posterior 1/3 interventricular septum

Question 27

posterior vein of LV

Answer 27

runs on diaphragmatic surface of LV, joins sinue to left of middle cardiac vein

Question 28

Vein of Marshall

Answer 28

oblique vein of left atrium
small vein running downwards on posterior LA into sinus
develops from left common cardinal vein (duct of Cuvier)