Flashcards in Cardiovascular System Deck (92):
What does the heart sit in
What is the mediastinum
Area in thorax between the lungs
Has heart, aorta, trachea and oesophagus
Describe the diaphragm muscle
Circumferential origin with fibers attaching to all walls
Central tendon attached to pericardial sac
When the diaphragm moves down what occurs?
Increases vol --> decr pressure --> air flows in
When the diaphragm moves up what occurs?
Decreases vol --> increases pressure --> air flows out
What are the two layers of pericardium?
Fibrous and serous
Where do you feel the apex beat of the heart
5th intercostal space on the left hand side
Right chambers lie in front of
Atria lie to the LEFT/RIGHT of ventricles?
wall of tissue that separates the right and left atria of the heart.
It has the fossa ovalis
Where is the fossa ovalis found
Right Atrium --> interatrial septum
What is the fossa ovalis
depression in the right atrium of the heart, the remnant of a thin fibrous sheet that covered the foramen ovale during fetal development.
What did the fossa ovalis used to be
What did the foramen ovale allow in a foetus
allows blood to pass from the right atrium to the left atrium, bypassing the nonfunctional fetal lungs while the fetus obtains its oxygen from the placenta.
patent foramen ovale
unfused fossa ovalis
Thickness of Right Atria
THIN --> receiving system
Where are ridges found in R.A?
Internal, anterior wall
What are the ridges in R.A called?
What veins does the R.A receive blood from
What valves are found in R.A?
Where does the SVC drain from?
Head, neck, upper limbs and thorax
Where does SVC 'pour' blood into?
What does the corony sinus drain
What does the corony sinus drain into
What does the IVC drain
Everything BELOW thorax
Where does the IVC drain into
Do ventricles or atria have thicker walls?
Ventricles since they are pumping
Which atria/ventricle has the thickest wall?
What ridges are found in ventricles
Where are the trabeculae carnae found in the right ventricle
except by the pulmonary artery
Where does the R.V receive blood from
Where does the R.V pump blood into
What valves are found in the R.V
What ridges are found in the left atria
NONE - completely smooth
Where does the left atria receive blood from
What valves are found in the left atria
Where is the mitral valve found
Between L.A and L.V
Where is the tricuspid atrioventricular valve found
b/w R.A and R.V
What is the difference between the trabeculae carnae of right and left ventricle
Right ventricle --> 3 papilary muscles with chordae tenderna attached to tricuspid AV
Left ventricle --> TWO papillary muscles with chordae tendernae attached to mitral valve
Where does the L.V receive blood from
Left atria --> oxygenated blood
Where does the L.V pump blood into
Aorta via aortic valve
Describe blood flow starting from deoxygenated blood from the body
Enters the R.A --> tricuspid valve --> R.V --> pulmonary valve --> pulmonary artery --> lungs --> pulmonary veins --> L.A --> Mitral valve --> L.V --> aortic valve --> aorta --> to the body :)
Atria or ventricles receive blood?
What is the function of the figure of 8 fibrous skeleton?
1. Attachment of atrial muscle mass and ventricular muscle mass
2. electrically isolates ventricles from atria
3. gives attachment to the tricuspid and mitral valves
Which two valves are semilunar valves
How many cusps do the semilunar valves have
Small collection of cardiac muscles
What are the two heart nodes
Where is the sinoatrial node located
Upper wall of the R.A
Where is the atrioventricular node located
Bottom of the right atrium
Describe electrical pulse
S.A node --> sweeps through muscle --> A.V node --> fibrous skeleton --> bundle of HIS --> LV & R.V
Where does the nerve supply of the heart come from
Cardiac plexus at the BOTTOM of the heart
What nervous system does the cardiac plexus originate from
BOTH sympathetic and parasympathetic
What does the cardiac plexus control
Rate of pump
What is the majory artery of the heart
Where is the right and left corony artery placed on the heart?
R --> infront of heart
L --> back of heart
What does the right corony artery supply
S.A and A.V
What does the L. corony artery supply
What does the ascending aorta supply
What does the arch of the aorta supply
Head, neck and upper body
What does the descending arota supply
Everything below the diaphragm
What is the first branch of the aorta
Feature of corony arteries
FUNCTIONAL end arteries
What are the three branches of the aortic arch
L common carotid art
L subclavian art
What is the flow of blood in the aorta
Brachiocephalic trunk --> cara --> subclavian
Duct between the pulmonary trunk and underside of the aorta.
It was once open and called ligamentum arteriosum in a baby
Ligamentum arteriosum becomes
What are the for descending thoracic aortic branches
What is the most variable vein system in the human body
What does the SCV split into
SVC --> brachiocephalic veins --> IJV & Subclavian veins
What does the brachiocephalic veins supply?
Arms and head
What does the IJV supply
Head and neck
What do the subclavian veins supply
What does IJV stand for
Internal jugular vein
What is the difference between the R and L brachiocephalic veins
R = short and vertical
L = long and horizontal because it runs through the midline
Difference between coronary sinus and coronary vein
The coronary sinus is the vein into which all the other cardiac veins drain. It then drains into the right atrium. It is carrying deoxygenated blood. The coronary arteries (right and left) come off the aorta and provide oxygenated blood to the heart
What are the four valves of the heart
What forms the right border of the heart
What forms the inferior border
What forms the left border of the heart
What forms the apex of the heart
Functions of the pericardium
Fixes heart in mediastinum and limits its motion
Protection from infections coming from other organs (such as lungs)
Prevents excessive dilation of heart in cases of acute volume overload
What are the two systems for gas exchange in the circulation of blood and what are their differences?
Pulmonary circulation -> right heart to lungs --> oxygenate blood
Systemic circulation -> left heart to body --> deliver oxygen
What type of artery is the aorta
What does the aorta divide into
Ascending aorta, arch and descending aorta
What does the BRANCH of the aorta divide into
Left common carotid
Left subclavian arteries
How is blood flow maintained in the vena caval system?
There are no valves
SVC has no backflow because of gravity, and blood is 'falling' into the atrium
IVC - ucking pressure of the atrium, the blood flow from the Lower Limbs which increases the pressure in the IVC, and the so-called thoracic pump
ventricles relax and are re-filled with blood from the atria
Is valve opening passive or active? What determines it?
What are the valves of the heart surrounded by and what does it do
supports them and prevents distension during ventricular contraction