Maj Dr Poonam Singh Department Of Anatomy Nepal Army Institute of Health Sciences

1. Blood supply of heart
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Maj Dr Poonam Singh
Dept Of Anatomy
Nepal Army Institute of Health Sciences

2. Learning objectives
•Coronary Arteries
• Origin
• Course
• Branches
•Dominance
•Anastomosis
•Variations
•Applied
•Venous return 2

3. Introduction
• Coronary arteries
• Vasa vasora arising from aortic sinuses of ascending
aorta
• Right - Right aortic sinus (right ant)
• Left – Left aortic sinus (left post)
• Post Aortic sinus - non coronary (Torus aorticus)
• Max filling of sinuses - in diastole
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4. 5

5. 6

6. 9

7. Crux
Meeting point of
•IA groove
• Post AV groove
•Post IV groove
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8. SA Node & AV Node location
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9. 13

10. Rt Coronary Artery
 Passes to rt & forwards
b/w infundibulum of rt
ven & rt auricle
 Runs downwards in ant
AV groove
 Reaches inf margin of
heart; winds around it to
the diaph surface; runs in
post AV groove
 Ends by anastomosing
with circumflex br of LCA
-60%
Conus brs
Ventricular brs
AV nodal br
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11. Branches of Rt coronary Artery
 Rt conus artery-
Annulus of Vieussens
 SA Nodal br – 60%
 Ant atrial branches
 Ant ventr branches
 Rt Marginal artery:
(Largest br)
 Post ventr branches
 Post IV br arises near
CRUX – 70% br of RCA
 Post atrial branches
 AV Nodal artery – 80%
Conus brs
Ventricular brs
AV nodal br
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12. Conus brs
Ventricular brs
AV nodal br
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13. Lt Coronary Artery
 Origin: Lt Aortic
sinus
 Passes behind
infundibulum of Rt
ventricle
 Length: 0 to 10mm
 Bifurcates into Ant
IV branch (LAD) &
Circumflex artery
Conus brs
Ventricular brs
AV nodal br
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14. LAD (Ant IV) artery
 Continuation of
LCA
 Extends beyond the
apex, ends by
anastamosing with
post IV artery (br of
RCA)
Branches:
 Ant ventr brs:
i. Diagonal arteries
ii. Lt Conus artery
 Septal branches
Conus brs
Ventricular brs
AV nodal br
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15. Circumflex artery
 Runs in Ant AV groove and post AV groove
 Terminates by anastamosing with RCA near crux
Branches:
i. Atrial brs
ii. Ventr branches
iii. SA nodal
(40% cases)
iv. Lt Marginal
v. Post IV br
(only 10% cases)
vi. Kugel’s artery
vii.AV nodal br
(10-20%)
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16. Branches of
Coronary arteries
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17. Coronary dominance
 CA that gives post IV branch is supposed to be
dominant
 Misleading term as LCA supplies greater part of
myocardium, but in 70% cases post IV is a br of RCA (Rt
coronary dominance)
 3 types – Rt (70%), Lt (20%) & Balanced (10%)
Clinical importance:
In Lt dominance a block in LCA affect entire Lt ventricle and IV
septum, while in Rt or balanced dominance a block in RCA at
least spares part (2/3) of septum and lt ventricle
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18. Summary:
RCA:
• Rt atrium
• Lt atrium (ant part)
• Rt ventr except a small strip along the Ant IV groove
• Diaphragmatic surface of Rt ventricle
• Post 1/3 of IV septum
• SA Node and AV Node in majority
• Most conducting system of heart except Lt branch of
Bundle of His
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19. LCA:
• Post part of Lt Atrium
• Ant and Lat walls of Lt ventricle
• Ant 2/3 of IV septum
• Lt br of Bundle of His
• SA & AV Nodes in 30% cases
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21. Coronary Anastomosis
-Anatomically CA are not end arteries but functionally
they behave like end arteries.
-Anastomosis occur at:
• superficial
• subepicardial
• Myocardial
• subendocardial levels
Important sites:
i) b/w terminations of RCA & LCA near crux of heart
ii) b/w their IV brs (in septum)
iii) b/w conus As
iv) apex
Prognosis better in slow occlusion
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22. Variations
Congenital anomalies
- LCA arising from Pul trunk; cyanosis occurs
- LCA arises from right aortic sinus; may get compressed b/w
Pul trunk & aorta in strenuous exercise; may cause sudden
cardiac death
- Post IV A arising from Cx A (left dominance)
- SA nodal A in 40% from Cx A; AV nodal A in 20% from Cx A
- LCA arising from Ant or post aortic sinus
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23. Post IV A arising from Circumflex br of LCA
Post IV Artery
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24. Single Coronary A

25. Circumflex br arises from rt aortic sinus

26. Venous Drainage
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27. Coronary Sinus
 Heart is drained by CS - empties into Rt Atrium.
 Two set of veins empty directly into Rt Atrium
 Venae cordis minimi
 Ant cardiac vein,
 s/t Rt marginal vein also
 CS - dilatation of Great Cardiac Vein located in post part of AV
groove
 Opens into Rt atrium b/w IVC and Tricuspid opening guarded
by incomplete semicircular “Thebasian valve”
 Tributaries- all have valves except oblique V of lt atrium
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28. Tributaries of Coronary sinus:
1. Great Cardiac vein
• Begins near apex of
heart; acc. Ant IV A &
more proximally cx
artery
• Terminates at lt end of
coronary sinus
2. Middle cardiac vein
• Accompanies Post IV
artery and opens at
termination of coronary
sinus
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29. 3. Small Cardiac vein
• Accompanies rt marginal artery
• Runs in AV groove to end into rt end of CS
• May open directly into rt atrium
4. Oblique Vein of Lt Atrium (of Marshall)
• Runs in the post surface of Lt Atrium and drains into Lt end of Coronary sinus
5. Post Vein of Lt Ventricle
• Runs on diaphragmatic surface of Lt ventricle and ends in middle of coronary
sinus
6. Rt Marginal vein
• Accompanies Rt Marginal artery and drains into Small Cardiac vein or directly
into the Rt Atrium 33

30. Oblique Vein of Lt Atrium (of Marshall)
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31. Veins directly emptying into Rt Atrium
1. Ant Cardiac Veins:
• 3-4 in no .drains the infundibulum of Rt ventricle
• opens into Rt Atrium through its Ant wall
2. Venae Cordis Minimi/ Thebasian veins
• Numerous small veins opening into the Post wall of
Rt Atrium
3. Small cardiac vein – may open directly into Rt atrium
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32. Applied Anatomy:
• Coronary Artery Disease (CAD)
• Coronary Angiography
• PTCA (Percutaneus Transluminal
Coronary Angioplasty)
• CABG ( Coronary Artery Bypass Graft)
• Cardiac catheterisation
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33. Coronary Artery Disease (CAD) & Ischaemic Heart
Diseases (IHD) – due to atherosclerosis
- Angina Pectoris – transient myocardial ischemia
- Myocardial Infarction – occlusive thrombus
Investigations for CAD & IHD
a) ECG
b) Coronary Angiography
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34. Treatment of CAD
1. Medical T/t for angina
2. Stents- simple or drug-eluting (vasodilators)
3. Coronary Angioplasty (PTCA) - single vessel disease
4. Coronary Artery Bypass Graft (CABG) – triple vessel disease
-median sternotomy
-thymus incised
-pericardium incised
-SVC & IVC cannulated, venous blood goes to bypass
machine
-graft used: reversed Gr Saph V or Int Th A
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36. M. I.
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37. STENTING
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39. 43

40. CABG
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41. CABG
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42. CORONARY
CATHETRISATION
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44. Thank
you
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