Anatomy and Physiology of Heart.

2. By Ghulam Rasool Baltistani
Anatomy Of Heart

3. The Heart
A hollow muscular organ that pumps the
blood through the circulatory system by
rhythmic contraction and dilation. In
vertebrates there may be up to four
chambers (as in humans), with two atria
and two ventricles.

4. Size of Heart
• The heart is relatively small, roughly the same
size (but not the same shape) as your closed
fist.
• It is about 12 cm long, 9 cm wide at its
broadest point, and 6 cm thick.
• It has an average mass of 250 to 300 grams.

5. Location of Heart
• The heart rests on the diaphragm, near the
midline of the thoracic cavity.
• Heart lies in the thoracic cavity in the
mediastinum and between the lungs.
• It lies obliquely, a little more (about 2/3) to
left than the right.
• Present a base above and apex below

6. Organ Associated With The Heart
• Inferiorly:
• The apex rest on the central tendon of the diaphragm.
• Superiorly:
• The great blood vessel aorta is located.
• Posteriorly:
• Esophagus, Trachea, Left and Right
bronchioles, Descending Aorta.
• Laterally:
• Lungs
• Anteriorly:
• Sternum, Ribs, Inter costal muscles.

7. Pericardium
• The membrane that surrounds and protects
the heart is the pericardium.
• It confines the heart to its position in the
mediastinum, while allowing sufficient
freedom of movement for vigorous and rapid
contraction.
• It consists of two main parts:
– Fibrous pericardium
– Serous pericardium

8. Layers of the Heart Wall
• The wall of the heart consists of three layers
– the epicardium (external layer)
– the myocardium (middle layer)
– the endocardium (inner layer).
• The epicardium is composed of two tissue layers.
The outermost, as you just learned, is called the
visceral layer of the serous pericardium.
• The middle myocardium is composed of cardiac
muscle tissue. It makes up approximately 95% of
the heart wall.
• The innermost endocardium is a thin layer of
endothelium overlying a thin layer of connective
tissue.

9. Layers of the Heart Wall

10. • “Tricuspid” valve
– RA to RV
• Pulmonary or pulmonic valve
– RV to pulmonary trunk (branches R and L)
• Mitral valve (the bicuspid one)
– LA to LV
• Aortic valve
– LV to aorta
Valves of The Heart

11. Chambers of the Heart
• Two atria-divided
• by interatrial septum
– Right atrium
– Left atrium
• Two ventricles
-divided by interventricular septum
– Right ventricle
– Left ventricle

12. References
Principles of
ANATOMY &
PHYSIOLOGY
Gerard J. Tortora
Bergen Community
College
Bryan Derrickson
Valencia Community
College