Arteries of the Heart

Question 1

Left coronary a.

Answer 1

Source: ascending aorta
Branches: anterior interventricular and circumlex brs
Supply: left atrium; most of left ventricle; anterior two-thirds of interventricular septum; AV bundle
Notes: May supply AV (in ~20%) &/or SA nodes

Question 2

Anterior interventricular a.

Answer 2

Source: left coronary
Branches: diagnoal br.
Supply: most of left ventricle; anterior two-thirds of interventricular septum; AV bundle
Notes: also called left anterior descending (LAD)

Question 3

Circumflex a.

Answer 3

Source: left coronary
Branches: left marginal br.; (posterior interventricular in 30%)
Supply: left atrium; side and back wall of left bentricle
Notes: may supply SA node

Question 4

Right coronary artery

Answer 4

Source: ascending aorta
Branches: SA nodal a.; right diagonal br.; right marginal br., posterior interventricular a.; AV nodal br.
Supply: right atrium; most of right ventricle; posterior third of interventricular septum
Notes: usually supplies AV node (in ~80%)

Question 5

Sinoatrial (SA) nodal a.

Answer 5

Source: right coronary in 60% (circumlex br. of left coronary in 40%)
Supply: SA node and surrounding myocardium

Question 6

Right marginal a.

Answer 6

Source: right coronary
Supply: lateral wall of right ventricle to apex

Question 7

Posterior interventricular a.

Answer 7

Source: right coronary in 70% (circumflex br. of left coronary in 30%)
Branches: AV nodal
Supply: Posterior third of interventricular septum
Notes: Also called posterior descending (PDA)

Question 8

Atrioventricular (AV) nodal a.

Answer 8

Source: posterior interventricular
Supply: AV node and surrounding myocardium