Lecture Topic 7: Anatomy of the Heart

What shape is the heart?

Cone shaped

What is the region between 2 lungs called?

Mediastinum

What are the main bones that protects the heart?

Ribs / sternum

Where does the apex of the heart lie in?

The 5th intercostal space in the midclavicular line 

State what covers the heart.

The pericardium

Briefly, what is the pericardium?

The coverings of the heart

What is the pericardium composed of?

An outer fibrous layer and an inner serous pericardium

What are the 3 properties of the fibrous pericardium?

Inelastic / fuses inferiorly with the diaphragm and superiorly with the great vessels / prevent overfilling of the heart and anchors it in position 

Why is the fibrous pericardium inelastic?

Bc its made of dense connective tissues

What is the centre of the diaphragm called?

Central tendon

The pink layer

Parietal pericardium 

Pericardial cavity 

Visceral pericardium

The green layer

Fibrous pericardium

How many layers are there in the serous pericardium?

Double layered 

What are the 2 layers in the serous pericardium?

Parietal / visceral layers

Where is the parietal layer in the serous pericardium?

Lines the inner surface of the fibrous pericardium

Where is the visceral layer in the serous pericardium?

Adheres to the surface of heart

What is another name for the visceral layer?

The epicardium 

What is the pericardial cavity?

Potential space between the parietal and visceral layers, contains pericardial fluid

Where is the pericardial cavity?

Between the parietal and visceral layer

What is the pericardial fluid for?

Prevents friction

What are the 3 layers of a heart wall?

Endocardium / myocardium / epicardium

What is the endocardium?

Inner layer - endothelium

What is the myocardium?

Middle layer - cardiac muscles

What is the epicardium?

Outer layer - visceral pericardium

Pericardial cavity 

Fibrous pericardium 

Parietal pericardium

Epicardium / visceral pericardium

Myocardium 

Endocardium

Auricle of left atrium

What is the purpose of the fibrous skeleton of the heart?

To electrically separate the artia from the ventricles

Chordae tendinae 

Papillary muscle 

Mitral valve

Tricuspid valve 

How are the AV valves attached to the heart?

Valves are anchored by the chordae tendineae to papillary muscles

What is the rate of blood flow to the heart (itself) ?

250 ml / min

When is blood delivered to the myocardium?

During ventricular relaxation

What does the LCA bifurcate into?

Anterior interventricular / circumflex

What does the RCA bifurcate into?

Posterior interventricular / marginal artery

What does angiography examine?

The patency of the coronary vessels?

What test could examine the patency of coronary vessel?

Angiography 

How is angiography carried out?

Catheter is inserted into the femoral artery that goes up to the aorta, where a dye is added. 

What are the 3 circulatory shortcuts in foetal circulation?

Foramen ovale / ductus arteriosus / ductus venosus 

What does the foramen ovale do?

Connects the right to left atria, bypass right ventricle and pulmonary system

What does the ductus arteriosus do?

Connects the pulmonary truck to arch of aorta, bypass pulmonary system and left side of heart

What does the ductus venosus do?

Connects umbilical vein to inferior vena cava, bypass the liver

What does the ductus venosus become in an adult?

Ligamentum venosum

What does the foramen ovale become in an adult?

Fossa ovalis

What does the ductus arteriosus become in an adult?

Ligamentum arteriosum

What happens to the ductus arteriosus when a newborn takes its 1st breath?

Lung expand / blood rush in pulmonary circulation / O2 lvl rises / constricts ductus arteriosus 

What happens to the foramen ovale when a newborn takes its 1st breath?

LA pressure increase, foramen ovale closes to become fossa ovalis