The heart receives its blood supply from two coronary arteries - the right and left coronary arteries. These branch directly off the aorta. The right coronary artery supplies the right atrium and ventricle as well as parts of the left ventricle and septum. The left coronary artery is larger and supplies the left atrium and ventricle as well as parts of the right ventricle. Blood is drained from the heart by the coronary sinus and smaller cardiac veins which drain into the right atrium. Disruptions to this delicate blood supply can cause chest pain or heart attacks.

1. BLOOD SUPPLY
TO HEART
By: Sathish Rajamani
Associate Professor

3. • Blood supply to the heart is also known as coronary
circulation. It consist of
I) ARTERIAL SUPPLY
II) VENOUS DRAINAGE
III) LYMPHATIC DRAINAGE

4. ARTERIAL
SUPPLY

5. • The heart receives its own supply of blood from the
coronary arteries.
• Two major coronary arteries branch off from the aorta
near the point where the aorta and the left ventricle meet.
These arteries and their branches supply all parts of the
heart muscle with blood.

6. RIGHT CORONARY
ARTERY
• Smaller than left coronary artery.
• Arises from anterior coronary sinus
Course:
Emerges from the surface of the heart between pulmonary trunk
and right auricle.
Winds around the inferior border to reach the diaphragmatic
surface to reach the posterior interior – ventricular groove.
Terminates by anastomosing with left coronary artery.

8. • Branches of the Right Coronary Artery
• Large Branches
Marginal
Post – Interventricular
• Small Branches
Right arterial
Infundibular
Nodal
Terminal

9. • Areas of Distribution
• Right Atrium
• Ventricles
• Greater part of right ventricle.
• Small part of left ventricle.
• Posterior part of the inter – ventricular
septum.
• Whole of the conducting system of the heart
except a part of the left branch of AV bundle.
The SA node is supplied by left – coronary
artery in 40% cases.

10. LEFT CORONARY
ARTERY
• Larger than the right coronary artery.
• Arise from left – posterior aortic sinus.

11. • Course:
• Runs forward and to the left and emerges between the
pulmonary trunk and the left auricle.
• Here the anterior inter-ventricular branch is given.
• The further continuation of the left coronary artery is
sometimes called the circumflex artery.
• After giving off the anterior inter-ventricular branch it
runs into the left anterior coronary sulcus.
• In winds around the left border and near posterior inter-
ventricular groove . It terminates by anastomosing with the
right coronary artery.

12. • Branches:
• Large Branches:
• Anterior Interventricular
• Branch to the diaphragmatic surface of the left ventricle.
• Small Branches:
• Left Atrial
• Pulmonary
• Terminal

13. • Areas of Distribution
• Left atrium
• Ventricles
• Greater part of the left ventricle, except the area adjoining
the posterior inter-ventricular groove.
• A small part of the right ventricle adjoining the anterior
inter-ventricular groove.
• Anterior part of the inter-ventricular septum.
• Part of left branch AV bundle.

14. COLLATERAL
CIRCULATION
• Cardiac Anastomosis: the two coronary artery anastomose to the
myocardium.
• Extra Cardiac Anastomosis: the cardiac arteries anastomosis with
other organ’s arteries.
• Vasa Vasorum of the aorta
• Vasa Vasorum of the pulmonary arteries
• Internal thoracic arteries
• The bronchial arteries
• Phrenic arteries
• These channels open up in the emergencies when the coronary
arteries are blocked.

15. CORONARY ARTERY
DOMINANCE
• The artery that gives the posterior inter-ventricular
artery determines the coronary dominance.
• RCA (Right Coronary Artery)
• CX (Circumflex Artery)

16. VENOUS DRAINAGE
•The venous drainage of the heart is
by 3 ways
•A. Coronary Sinus
•Anterior Cardiac Veins
•Venae Cordis Minimae

17. • Coronary Sinus – this is the largest vein of the heart
situates in the left posterior coronary sulcus. It is about 3
cm long and ends by opening into the posterior wall of the
right atrium.
• Its Branches are
• Great Cardiac Vein – it enter the left end of the coronary
sinus.
• Middle Cardiac Vein – it accompanies the posterior inter-
ventricular artery and joins the right end of the coronary
sinus.
• Small Cardiac Veins – it accompanies the right coronary
artery and joins the right end of the coronary sinus.

18. • Posterior vein of Left Ventricle: it runs on the
diaphragmatic surface of the left atrium and ends in the
middle of the coronary sinus.
• Oblique vein of the left atrium – it runs on the posterior
surface of the left atrium , joins the left end of coronary
sinus and develops from the left common cardinal veins.
• The right marginal veins – it accompanies the marginal
branch of the right coronary artery.

19. • ANTERIOR CARDIAC VEINS – 3 – 4 small veins run on
the anterior wall of the right ventricle, open directly into
the right atrium.
• VENAE CORDIS MINIMAE
• Numerous small veins present in all 4 chambers of the
heart which opens directly into the cavities.
• The thebesian venous network is considered as an
alternative pathway for venous drainage of the
myocardium.

20. LYMPHATIC NETWORK
• It accompanies the coronary artery and form 2 trunks.
• Rt trunk ends in bracheocephalic nodes and the left trunk
into the tracheobronchial lymph nodes at the bifurcation of
the trachea.

21. Applied Anatomy
• Angina Pectoris – Severe chest pain due to ischaemia of the
heart.
• Angina pectoris is due to the narrowing of the arteries.
• Myocardial Infarction - it means necrosis of a part the
myocardium due to severe prolonged ischaemia due to ischaemia
of coronary arteriies.
• Occlusion of the one of the coronary arteries or its branches.