Internal Anatomy of The Heart Flashcards
What does the right atrium communicate with?
The right ventricle
What does the left atrium communicate with?
The left ventricle
What guards the opening between the atria and the ventria?
The atrioventricular valves
Where are the atrioventricular valves found?
In the opening between the atria and the ventria
What do the AV nodes do?
The permit blood flow in one direction only - atria to ventricles
What separates the atria?
An interatrial septum made of muscle
What is the role of the interatrial septum?
It separates the atria
What is the foramen ovale?
3
A connection between the atria in the foetus
It closes soon after birth to form the fossa ovalis
If it doesn’t close it causes a hole in the heart
What is the name of the connection between the atria in the foetus called?
The foramen ovale
What is a closed foramen ovale called?
Fossa ovalis
From where does the right atrium receive blood?
3
Superior Vena Cava
Inferior Vena Cava
Coronary sinus
What directs blood in the atrium downwards?
Ridges in the walls of the atrium
What does the superior vena cava do?
It drains the head, neck, upper limbs and chest
What does the inferior vena cava do?
It drains blood from the rest of the trunk, the viscera and lower limbs
What does the coronary sinus do?
Drains blood from the coronary veins
What muscles make up the right atrium?
Pectinate muscles
What are pectinate muscles?
2
Muscles containing prominent muscular ridges
Found on arterior wall and inner surfaces of right auricle
What wall of the atrium has ridges?
The right wall
Other than the right wall of the atrium, where are ridges present?
The auricle
Why are auricles named so?
When they aren’t filled with blood they deflate and look like an auricle/ear
Where does the right ventricle receive it’s blood from?
From the right atrium
What binds the opening into the right ventricle?
The tricuspid valve
How are the cusps of the tricuspid valve attached?
Attached to the walls of the right ventricle by fibrous cords (Chordae Tendinae)
How are Chordae Tendinae attached to the wall of the right ventricle?
By papillary muscle
What are the chordae tendinae also called?
Heart strings
Other than chordae tendinae what does the papillary muscle attach?
The moderator band
What does the right ventricle empty into?
The pulmonary trunk
What guards the opening of the pulmonary trunk?
The pulmonary semilunar valve - a 3 cusped (tricuspid) valve
From where does the left atrium receive blood?
Receives blood from the two left and two right pulmonary veins
How is blood passed from the left atrium to the left ventricle?
Via the lest AV valve
What is the AV valve between the LA and LV also called?
The mitral valve (its a 2 cusped bicuspid valve_
Where does blood exist the left ventricle?
At the aortic semilunar valve
Where is the aortic semilunar valve attached?
Its attached to the ascending aorta by extensions called the aortic sinuses
How is the LV different from the RV?
2
The LV is larger and the muscle is thicker
Has no moderator band
Name the two semilunar valves.
Pulmonary tricuspid valve
Aortic tricuspid valve
What do the semilunar valves do?
They prevent backflow from pulmonary trunk and aorta into ventricles
Describe the structure of the semilunar valves.
2
Have no muscular support
Three cusps support like tripod
Where are the aortic sinuses?
At the base of the ascending aorta
What are the aortic sinuses?
2
They are sacs that prevent valve cusps from sticking to aorta
They are the origin of the right and the left coronary arteries
What is the blood supply to the heart muscle called?
Coronary circulation
What makes up the coronary circulation?
Coronary arteries
Cardiac veins
What makes up the coronary arteries?
The right and left coronary arteries and their branches
What does the right coronary artery supply with blood?
3
The right atrium
The posterior ventricles
Portions of the conducting system
What does the left coronary artery supply with blood?
3
The left atrium
The anterior surface of the left ventricle
The interventricular septum
What is anastomosis?
Interconnections of the branches of the coronary arteries
What do coronary veins do?
3
The drain the heart muscle of blood
They untie to form the coronary sinus
The empty into the right atrium
Name the four coronary veins.
The great cardiac vein
The posterior cardiac vein
The middle cardiac vein
The anterior cardiac vein
