Human Heart Anatomy

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Questions and Answers

What is the approximate weight of the heart?

400 g

500 g

200 g

300 g (correct)

What is the outermost layer of the heart wall?

Endocardium

Myocardium

Pericardium

Epicardium (correct)

What is the shape of the heart?

Pyramidal (correct)

Cylindrical

Spherical

Elliptical

What is the direction of the apex of the heart?

Forward, downward, and to the left Signup and view all the answers

What forms the base of the heart?

Left atrium and a small part of the right atrium Signup and view all the answers

How many surfaces does the heart have?

4 Signup and view all the answers

What is the innermost layer of the heart wall?

Endocardium Signup and view all the answers

Where is the heart located in relation to the median plane?

Two-thirds to the left of the median plane Signup and view all the answers

Which part of the heart is separated from the base by the posterior part of the coronary groove?

Coronary sinus Signup and view all the answers

What is the name of the groove that divides the atrial and ventricular portions of the heart?

Atrioventricular groove Signup and view all the answers

Which surface of the heart is formed by the left ventricle?

Left 1/3 of the diaphragmatic surface Signup and view all the answers

What is the name of the groove that divides the right and left ventricles?

Anterior interventricular groove Signup and view all the answers

Which part of the heart lies opposite the 5th-8th thoracic vertebrae?

Base of the heart Signup and view all the answers

What is the name of the surface of the heart that is formed by the right atrium?

Right surface Signup and view all the answers

What is the name of the groove that lies between the right and left ventricles?

Anterior interventricular groove Signup and view all the answers

Which part of the heart is formed by the left and right auricles?

Atrial portion of the heart Signup and view all the answers

What is the outermost layer of the pericardium?

Fibrous pericardium Signup and view all the answers

What is the function of the pericardial cavity?

To allow for the movement of the heart Signup and view all the answers

What is the apex of the heart directed towards?

Upwards Signup and view all the answers

What is the purpose of the phrenic nerves in relation to the pericardium?

To innervate the diaphragm and fibrous pericardium Signup and view all the answers

What is the visceral layer of the serous pericardium also known as?

Epicardium Signup and view all the answers

How much fluid is typically present in the pericardial cavity?

5-30 mL Signup and view all the answers

What is the fibrous pericardium attached to inferiorly?

The central tendon of the diaphragm Signup and view all the answers

What is the location of the base of the fibrous pericardium?

On the diaphragm Signup and view all the answers

Study Notes

The Heart

Located in the middle mediastinum, deep to the sternum, tilted towards the left, with about two-thirds of the heart lying to the left of the median plane.
Weighs approximately 300 g (10 oz).
Measures around 13 cm * 9 cm * 6 cm in size.
The heart is roughly the same size as a fist, regardless of body size.

The Heart Wall

Consists of three layers: epicardium, myocardium, and endocardium.
Epicardium: outer thin layer, covers the external surface of the heart.
Myocardium: middle thick muscular layer.
Endocardium: inner thin layer, lines the interior of the chambers and forms the valves.

Shape of the Heart

Like a pyramid resting on one of its sides.
Apex: projects forward, downward, and to the left.
Base: faces backward and upward.
The heart has four surfaces: inferior (diaphragmatic), anterior (sternocostal), right pulmonary, and left pulmonary.

Surface Anatomy

The apex of the heart is formed by the left ventricle and lies in the left 5th intercostal space, 3.5 inches from the median plane, at the midclavicular line.
The base of the heart is formed mainly by the left atrium and a small part by the right atrium, and lies opposite the middle four thoracic vertebrae (5th-8th).

The Pericardium

A fibroserous sac that surrounds the heart and the beginning of great vessels.
Consists of two parts: outer fibrous layer (fibrous pericardium) and inner serous sac (serous pericardium).
The fibrous pericardium is a cone-shaped bag attached to the diaphragm and the posterior surface of the sternum.
The serous pericardium is formed of two layers: parietal layer and visceral layer (epicardium).
The parietal and visceral layers of serous pericardium are continuous at the roots of the great vessels.
The pericardial cavity is a narrow potential space created between the two layers of serous pericardium, containing a small amount of fluid (5 to 30 mL) and allowing the movement of the heart.