Internal features of Internal features of HeartHeart

Dr. Sama ul HaqueDr. Sama ul Haque

ObjectivesObjectives

List the chambers of the heart.

Describe the internal features of right atrium.

Describe the internal features of the right ventricle.

Discuss internal features of the left atrium.

Discuss the internal features of the left ventricle.

Differentiate between right and left ventricles.

Define conducting system of the heart.

Chambers of Heart

1.Right Atrium

2.Right Ventricle

3.Left Atrium

4.Left Ventricle

Chambers of Heart

Internal Structure of Heart

Right Atrium

Crista Terminalis

Musculi pectinati(Pectinate muscles)

1. Rough anterior part.

2. Smooth posterior part. 1

2

Posterior wall of the right atrium:

• Opening of the superior vena cava

• Opening and valve of the inferior vena cava

• Opening and valve of the coronary sinus

• Fossa ovalis and the limbus fossa ovalis

Anterior wall of the right atrium:

• Pectinate muscles

• Crista terminalis

Right Atrium

Right Ventricle

• Tricuspid valve has three cusps: anterior, septal, and posterior.• Three papillary muscles: anterior, septal, and posterior. The

anterior papillary muscle is the largest and most prominent.

• Trabeculae carneae (rough muscular ridges).

Right Ventricle

• The septomarginal trabecula (moderator band): extends from the interventricular septum to the base of the anterior papillary muscle.

• The conus arteriosus (infundibulum): is the cone-shaped portion of the right ventricle inferior to the opening of the pulmonary trunk.

• The pulmonary valve: consists of three semilunar cusps: anterior, right, and left.

Right Ventricle

Right Ventricle

Left Atrium• Receives blood from

lungs: Through 4 pulmonary veins (2 right & 2 left)

• Bicuspid valve: blood passes through it into left ventricle (mitral valve has two cusps).

• Aortic valve: has three semilunar valve cusps: right, left, and

posterior.

• Left atrioventricular valve (bicuspid valve or mitral valve):

has anterior & posterior cusps.

Left Ventricle

• Anterior papillary muscle and the posterior papillary muscle:

the chordae tendineae of each papillary muscle attach to both

valve cusps.

• Trabeculae carneae.

Left Ventricle

Left Ventricle have thick muscular wall

Valves of the Heart

1

23 4

1. Right Atrioventricular (Tricuspid)

2. Left Atrioventricular (Bicuspid or Mitral)

3. Pulmonary

4. Aortic

Fibrous Skeleton of the HeartDense collagenous fibrous tissue framework lies at the junction of the atria with the ventricles.Includes:1-Tricuspid fibrous annulus: 2-Mitral fibrous annulus3-Pulmonary fibrous annulus: 4-Aortic fibrous annulusFunctions:1-Supports the valves. 2-Electrically separetes atria from ventricles.

Valves of the Heart

Valves of Heart in Diastole (Viewed from base with atria removed)

Valves of Heart in Systole (Viewed from base with atria removed)

Direction of blood flow

Sinu-Atrial Node (S-A Node)Sinu-Atrial Node (S-A Node)

Atrio-ventricular Node (A-V Node)Atrio-ventricular Node (A-V Node)

Atrio-ventricular BundleAtrio-ventricular Bundle

Right and left Bundle branchRight and left Bundle branch

Purkinje FibersPurkinje Fibers

Conducting system of HeartConducting system of Heart

Conducting system of HeartConducting system of Heart

S-A Node

A-V Node

Conducting system of HeartConducting system of Heart

PF

Conducting system of HeartConducting system of Heart

Thank YouThank You