C h a p t e r 1 9
Disorders of Cardiac Function
445
and the anterior papillary muscle of the left ventricle.
The
circumflex branch
of the left coronary artery passes
to the left and moves posteriorly in the groove that sepa-
rates the left atrium and ventricle, giving off branches
that supply the left lateral wall of the left ventricle. The
right coronary artery
lies in the right atrioventricular
groove, and its branches supply the right ventricle. The
right coronary artery usually crosses to the back of the
heart, where this vessel forms the
posterior descending
artery,
which, in most individuals, supplies the posterior
portion of the heart, interventricular septum, sinoatrial
(SA) and atrioventricular (AV) nodes, and posterior pap-
illary muscle.
4–6
The right and left coronary arteries or epicardial
arteries branch into smaller intramyocardial arteries,
which penetrate the myocardium before merging with a
FIGURE 19-1.
Coronary circulation.
(A)
Anterior view of the coronary arteries.
(B)
Posterior view of the coronary arteries
and coronary sinus veins. (From Moore
KL, Dalley AF, Agur AMR. Clinically
Oriented Anatomy. 6th ed. Philadelphia,
PA: Wolters Kluwer Health | Lippincott
Williams &Wilkins; 2010:146.)
A
Anterior view
Site of
SA node
Sinu-atrial (SA)
nodal branch
Right coronary
artery (RCA)
within coronary
sulcus
Right marginal
branch of RCA
Arch of aorta
Ascending
aorta
Pulmonary
trunk
Left main coronary
artery (LCA)
Circumflex branch
of LCA
Anterior
interventricular
branch of LCA
Left marginal
artery
Lateral (diagonal)
branch of anterior
IV branch
Apex of heart
Posterior interventricular
branch within posterior
interventricular groove
Atrioventricular
(AV) nodal branch
of RCA
Left anterior
descending artery
B
Posteroinferior view
Arch of aorta
Superior vena
cava (SVC)
Sinu-atrial (SA)
nodal branch
of RCA
Right
pulmonary
veins
Right
coronary
artery (RCA)
Atrioventricular
nodal branch of RCA
Right marginal
branch of RCA
Posterior
interventricular
branch of RCA
Left pulmonary
artery
Left coronary
artery (LCA)
Circumflex branch
of LCA within
coronary sulcus
Site of AV node
Crux of heart
Anterior
interventricular
branch of LCA
