1. By Prof. Saeed Abuel Makarem
THE HEART By
Prof.
Saeed Abuel Makarem

2. Pericardium
A fibro-serous sac
Surrounds the heart & proximal part of its great vessels (Aorta, Pulmonary artery, SVC, IVC, & 4 pulmonary veins)
Formed of:
Outer fibrous layer
Inner serous sac
Serous sac has 2 layers:
Parietal & Visceral (epicardium)

3. Fibrous Pericardium Conical or flask shape
Apex: directed upwards fused with adventitia of 3 big vessels
Base: rests on diaphragm
Fuses with central tendon of diaphragm.
Posteriorly: Separated by post. Mediasinum from middle four thoracic vertebrae (5 to 8)
Anteriorly: body of sternum, costal cartilages from 2 to 6, ant. Border of lung & pleura, remains of thymus gland & two Sterno-pericardial ligaments
Extends from 2nd to 6th rib

5. Located in the middle mediastinum
posterior to the body of sternum and 2nd-6th costal
cartilages
Anterior to T5-T8 vertebrae
1-1.5 cm to the right of the sternum
5-7.5 cm to the left of median plane at the level of 5th intercostal space

6. Function of serous pericardium:
1- Lubrication to prevent friction
2- Prevent adhesion of the heart to its surrounding

7. Function of fibrous pericardium
1- Maintain the central position of the heart
2-Keeps large vessels open
3-Helps venous return
4-Acts as a wall for the serous
pericardium.
5- Prevents over loading & overdistention of the heart
Serous pericardium
Serous sac that has been invaginated by developing heart in the fetal life
Visceral layer: Epicardium.
Parietal layer: Lines the fibrous pericardium
Pericardial cavity: potential space.

8. Sinuses of pericardium
2 sinuses in the serous pericardium are formed during development of the heart (Transverse & Oblique)
Transverse sinus
A recess behind pulmonary trunk & ascending aorta
Boundaries:
Ant: Pulmonary trunk & ascending aorta.
Post: SVC &Upper part of the 2 atria
Above: Rt. Pulmonary artery
Below: the 2 atria mainly Lt.

9. Oblique sinus
It separates the base of heart (left atrium) from posterior mediastinum (descending aorta & esophagus)
Boundaries:
Ant: back of Lt. atrium
Post: fibrous pericardium & posterior mediastinum (esophagus & descending aorta )
Left: 2 Left pulmonary veins
Right: 2 right pulmonary veins & IVC

12. Blood Supply
Arterial Supply:
Mainly supplied by pericardiophrenic and musculophrenic arteries, branches of internal thoracic
Also supplied by pericardial branches of bronchial, esophageal and superior phrenic arteries
Visceral layer of the serous pericardium (epicardium) supplied by the branches of the coronary arteries
Venous drainage: Veins are tributaries of azygos system.
Pericardiophrenic veins also drain into the internal thoracic vein

13. Nerve Supply
The fibrous pericardium and the parietal layer of the serous pericardium are supplied by the phrenic nerves.
The visceral layer of the serous pericardium is innervated by (autonomic fibers) branches of the sympathetic trunks and the vagus nerves

14. Heart Muscular pump that keeps circulation going on.
It is the size of hand’s fist of the same person
2/3 of its breadth lies to left of median plane and 1/3 right to median plane
It is conical in shape having an apex, base,
Sterno-costal, diaphragmatic, surfaces
and right, and left borders.

15. External Features: Surfaces
The heart has:
Sternocostal (Anterior) surface
Diaphragmatic (Inferior) surface
Base (Posterior surface)
Apex

16. Directed downwards, forwards & to left
Apex
Directed downwards, forwards & to left
Lies in LT. 5th Intercostal space 3 & ½ inches ( 9 cm) from median plane.
Formed only by LT. ventricle.
Pericardium & diaphragm separate the apex from fundus of stomach

17. Base
Directed backwards and slightly to right.
Formed by 2 atria mainly the left atrium.
Separated from post Mediastinum by oblique sinus of pericardium
Lies opposite middle 4 thoracic vertebrae (5 to 8)
Bounded inferiorly by coronary groove that lodge the coronary sinus.

18. Sternocostal surface

19. *Sterno-costal surface
Lies behind body of sternum & 3rd to 6th costal cartilages.
Divided by coronary groove into:
Atrial part: Rt. Atrium
Ventricular part: the two ventricles, mainly Rt.
Borders:
Upper: Straight, formed by the 2 atria but concealed by the ascending aorta & pulmonary trunk.
Lower: Concave formed by Rt. Ventricle & small apical part of Lt ventricle
Rt.: Convex formed by Rt. Atrium
Lt.: Convex ,formed by Lt. auricle and Lt. ventricle.

20. Diaphragmatic surface
Left 2/3 of this surface are formed by Lt ventricle
Rt. 1/3 is formed by Rt. Ventricle
The 2 ventricles are separated by post. Interventricular groove.
The groove lodges the post. Interventricular artery & middle cardiac vein

21. Surface anatomy of Heart
Point 1: Lower border of 2nd Lt costal cartilage one & half inches from the median plane.
Point 2: Upper border of Rt. 3rd costal cartilage one inch from median plane.
Point 3: Upper border of Rt. 6th costal cartilage one inch from its junction with the sternum.
Point 4: Apex Lt. 5th Intercostal space 3 ½ inches from median plane.

23. Surface anatomy of the valves
Pulmonary: Left 3rd sternocostal junction
Aortic: Left 3rd Intercostal space just left to sternum
Mitral: Left 4th sternocostal junction
Tricuspid: 4th Intercostal space near the middle line.

24. Auscultation of the cardiac valves
Surface anatomy A
Auscultation of the cardiac valves

25. Arterial Supply It is supplied by right & left coronary arteries
Coronary arteries arise from the ascending aorta immediately above the aortic valves
Coronary arteries and their branches are distributed over the surface of the heart lying within the subepicardial connective tissue

26. Right Coronary Artery Arises from anterior sinus of ascending aorta
Runs between the pulmonary
trunk and right auricle
Runs in the atrioventricular groove
At the inferior border of the heart it turns posteriorly in the atrioventricular groove
Anastomosis with a branch from the left coronary artery in the posterior interventricular groove

27. Right Coronary Artery: Branches
1-Right conus artery
2-Anterior ventricular branches: 2-3 in number,
3-Marginal branch
4-Posterior ventricular branches, which gives a
branch to atrioventricular node
6-Posterior interventricular artery
7-Atrial branches, & artery of the sinuatrial node which also supplies atria

28. Left Coronary Artery Larger than the right
Supplies major part of the heart
Arises from the left posterior aortic sinus
Runs between the pulmonary trunk and left auricle
Runs in the atrioventricular groove
Divides into anterior interventricular & circumflex branches

29. Left Coronary Artery: Branches
Anterior interventricular artery, which gives a small conus artery
Circumflex artery, gives:
Left marginal
Anterior ventricular
Posterior ventricular
Atrial branches

30. Coronary Artery Anastomoses
Although anastomosis do exist between the terminal branches of the right and left coronary arteries,
But these are not large enough to compensate for any sudden blockage of a large branch.
A sudden blockage of the larger branches results in myocardial infarction.

31. Venous Drainage of the Heart
Most of the blood drains into the right atrium through the coronary
sinus.
Coronary sinus:
Lies in the posterior part of the atrioventricular
It is the continuation of the great cardiac vein
Opens into the right atrium to the left of the inferior vena cava
Tributaries: small and middle cardiac veins, posterior vein of the left ventricle, oblique vein of the left atrium
Anterior cardiac veins drain directly into the right atrium
Vena cordis minimi open directly into heart chambers

32. anterior