Cardiac Anatomy And Physiology Flashcards
Where does the right atrium receive deoxygenated blood from
Superior and inferior vena cava
Coronary veins
What kind of blood does the right atrium receive
Deoxygenated
What is an auricle
A muscular pouch
How many parts does the right atrium have
2
What are the two parts of the right atrium
Sinus venarum
Atrium proper
Describe the structure and function of the sinus venarum in the right atrium
Has smooth walls
Receives blood from the vena cava
Describe the structure of the atrium proper in the right atrium
Rough, muscular walls formed by pectinate muscles
What separates the sinus venarum and the atrium proper in the right atrium
Crista terminalis
What is the function of the crista terminalis
Muscular ridge that separates the sinus venarum and the atrium proper
What is the structure in the right atrium that has smooth walls and receives blood from the vena cava
Sinus venarum
What is the structure in the right atrium that is a rough, muscular wall formed by the pectinate muscles
Atrium proper
What kind of blood enters the left atrium
Oxygenated
Where does the left atrium receive its blood from
The 4 pulmonary veins
What is the interatrial septum
Solid muscular wall that separates left and right atria
What is the name of the structure that separates the left and right atria
Interatrial septum
What is the fossa ovalis
Small oval shaped depression in the interatrial septum
What is the small oval shaped depression in the interatrial septum called
Fossa ovalis
How is the fossa ovalis formed
Small remnant of the foramen ovale in the fetal heart
What occurs if the foramen ovale doesn’t close
Causes a defect called patent foramen ovale
What is patent foramen ovale
Defect caused when the foramen ovale doesn’t close
What is trabeculae carnae
Muscular ridges in the ventricles
What are the series of muscular ridges in the ventricles called
Trabeculae carnae
What is the function of the papillary muscles
Connect the ventricle walls to the tricuspid/ bicuspid valve cusps via chorda tendinae
What does the interventricular septum do
Separates the two ventricles
What separates the two ventricles
Interventricular septum
What are the two parts of the interventricular septum
Superior membranous part
Inferior muscular part
How many parts does the interventricular septum have
2
What are the 4 valves of the heart
Tricuspid
Bicuspid
Pulmonary semilunar
Aortic semilunar
How many valves does the heart have
4
What are the three parts of the tricuspid valve
Anterior
Septal
Posterior
What are the two parts of the bicuspid valve
Anterior and posterior
What is the bicuspid valve supported by
Chordae tendineae
Explain how the bicuspid valve is supported
Chordae tendineae attached ti the free edges of the valve cusps which then connect to the papillary muscles
Where are the pulmonary semilunar valves located
Right ventricle and pulmonary trunk
How many cusps do semilunar valves have
3
What are the 3 different parts of the pulmonary semilunar valve
Left, right and anterior
Where is the aortic semilunar valve located
Between left ventricle and aorta
What are the 3 parts of the aortic semilunar valve
Right, left and posterior
What is stenosis
Valves doesn’t open properly
What is regurgitation
Valves dont close properly
What are the 3 common causes of stenosis
Increasing age
Congenital defect
Rheumatic fever
What ae the 3 common causes of regurgitation
Endocarditis
Post myocardial infarction
Rheumatic fever
Describe the structure of pericardium
2 main layers- fibrous- tough outer layer
-serous- inner layer- further divided Into parietal and visceral
Parietal lines inner surface of fibrous pericardium
Serous lines surface of heart
Space between serous layers- pericardial cavity
What is the pericardial cavity
Space between the parietal and visceral layer
Where do the left and right coronary arteries originate from
Aorta
What arteries originate from the aorta
Right and left coronary arteries
What coronary arteries originate from the right coronary artery
Right marginal
Posterior interventricular
The right marginal and posterior interventricular originate from what artery
Right coronary artery
What coronary arteries originate from the left coronary artery
Anterior interventricular
Left marginal
Left circumflex
Where do the anterior interventricular, left marginal and left circumflex arteries arise from
Left coronary artery
Where does the right coronary artery supply blood to
Right atrium and ventricle
What artery supplies blood to the right atrium and ventricle
Right coronary artery
Where does the left circumflex artery supply blood to
Left atrium and ventricle
What artery supplies blood to the left atrium and ventricle
Left circumflex artery
Where does the right marginal artery supply blood to
Right ventricle and apex
What artery supplies blood to the right ventricle and apex
Right marginal artery
Where does the left anterior descending artery supply blood to
Right and left ventricle
Interventricular septum
What artery supplies blood to both ventricles and the interventricular septum
Left anterior descending artery
Where does the left marginal artery supply blood to
Left ventricle
What artery supplies blood to the left ventricle only
Left marginal artery
What is the interarterial septum
Solid muscular wall- seperates atria
What is the fossa oval is
Small oval-shaped depression in septum
Remenant of foramen ovals in fetal heart
Give 3 differences between a pacemaker potential and a cardiac ventricular action potential
Pacemaker potential - no stable resting membrane potential
CVAP- resting potential close to -90mV
PP- natural automaticity
CVAP- awaits AP from SAN or adjacent cardiac myocyte for activation
PP- main depolarisation due to Ca2+ influx
CVAP- main depolarisation due to Na+ influx
What are the 8 different structural parts of an artery
Lumen
Endothelium
Tunica intima
Internal elastic lamina
Tunica media
External elastic lamina
Tunica externa
Adventitia
What is the lumen of the artery
Hollow tube of artery
What is the endothelium
Single layer of flat cells- in contact with blood
What is the tunica intima
Innermost layer of artery
Consists of endothelial cells and connective tissue
What is the internal elastic lamina
Elastin-rich tissue
Located between tunica intima and tunica media
What is the tunica media
Middle layer of artery
Composed of smooth muscle cells and elastic fibres
What is the external elastic lamina
Layer of elastic tissue between tunica media and tunica externa
What is the tunica externa
Outermost layer of artery
Composed of connective tissue, collagen fibres and loose fibroblasts
What is adventitia
Outermost layer of artery- also referred to as tunica externa
Composed of connective tissue and collagen fibres
In larger vessels- contain vasa vasorum- small blood vessels that supply nutrients to vessel wall
For the generation of a pacemaker potential, what happens when the end of one action potential causes hyperpoplarisation
Hyperpolaristaion activated cyclic nucleotide gated channels (HCN channels) open
Allows Na+ to enter
Creates slow depolarisation
What occurs in the generation of a pacemaker potential after hyperpolarisation activated cyclic nucleotide gated channels open, and Na+ enters causing a slow depolarisation
Voltage gated Ca2+ channels open once HCN channels get membrane back to threshold
This allows influx of Ca2+- increase depolarisation rate
Peak of AP- Ca2+ channels inactivate- K+ channels open
What occurs in the generation of a pacemaker potential after depolarisation occurs due to an influx of Ca2+ causing Ca2+ channels to inactivate and K+ channels to open
K+ channels open and K+ leave- causes repolarisation
HCN channels reactivated by negative membrane potentials
New AP able to be generated
Describe a cardiac action potential
Voltage gated Na+ channels open- Na+ in
Transient opening of voltage gated K+ channels- K+ out
Voltage gated Ca2+ channels open- Ca2+ balances out K+ out
Ca2+ channels inactivate
K+ channels open- K+ out
Back to resting membrane potential
