Teach me anatomy heart Flashcards
At what level does the pulmonary trunk split into the right and left pulmonary arteries
T5-T6
At what level does the superior vena cava drain into the right atrium
Level of 3rd rib
At what level does the inferior vena cava pass through the diaphragm and enter the pericardium
Level of T8
Where does blood leaving the left ventricle go
Passes into the aorta
Enters systemic circulation
Where does blood leaving the right ventricle go
Pulmonary circulation via pulmonary arteries
What is the role of the right auricle
Muscular pouch acts to increase the capacity of the atrium
What separates the inferior surface of the right atrium
Crista terminalis
Where does the coronary sinus open into
Right atrium
Between the inferior vena cava orifice and the right atrioventricular orifice
Describe the interatrial septum
Solid muscular wall that separates the right and left atria
What is the fossa ovalis
Remnant of the foramen ovale
What was the role of the foramen ovale
Allows right to left shunting of blood to bypass the lungs
Closes once the newborn takes its first breath
What does the left atrium receive blood from
Oxygenated - 4 pulmonary veins
What are the series of irregular muscular elevations called found in the right and left ventricle
Trabeculae carnae
What is the rate at which the SA node generates impulses influenced by
Autonomic nervous system
- sympathetic
- parasympathetic
What is the effect of the sympathetic nervous system on the heart
Increases firing rate of the SA node
Increases HR
What is the effect of the parasympathetic nervous system on the heart
Decreases firing rate of the SA node
Decreases HR
Where is the atrioventricular node located
Within the atrioventricular septum
Near the opening of the coronary sinus
What is the role of the AV node
Delay impulses
Ensure the atria have enough time to fully eject the blood into the ventricles before ventricular systole
How long does the AV node delay impulses
120ms
Where are purkinje fibres located
Sudendocardial surface of the ventricular walls
What are the three layers of the heart
Endocardium
Myocardium
Epicardium
Describe the endocardium
Innermost layer
Lines the cavities and valves of the heart
Regulates contractions
Describe the subendocardial layer
Lies between and joins the endocardium and myocardium
Purkinije fibres located here
Describe the myocardium
Composed of cardiac muscle
Involuntary striated muscle
Responsible for the contractions of the heart
Describe the subepicardial layer
Lies between and joins the myocardium and the epicardium
Describe the epicardium
Outermost layer
Formed by the visceral layer of the pericardium
What is significant about the epicardium
Connective tissue secretes small amount of lubricating fluid into the pericardial cavity
What is the outer surface of the epicardium lined by
Simple squamous epithelial cells
What is the pericardium
Fibro-serous
Fluid filled
Sack that surrounds the muscular body of the heart and the roots of the great vessels
What are the layers of the pericardium
Tough external layer - fibrous pericardium
Thin internal layer - serous pericardium
Describe the fibrous pericardium
Continuous with the central tendon of the diaphragm
Made of tough connective tissue
Relatively non-distensible
Rigid structure prevents overfilling of the heart
Describe the serous pericardium
Enclosed within the serous pericardium
Divided into two layers
What are the two layers of the serous pericardium
Outer parietal layer
Internal visceral layer
What does the outer parietal layer of the serous pericardium line
Internal surface of the fibrous pericardium
What does the internal visceral layer of the serous pericardium form
The outer layer of he heart - epicardium
What are the two layers of the serous pericardium made up of
Single sheet of epithelial cells - mesothelium
How do you remember the layers of the heart
Fart
Police
Smell
Villains
What does Fart Police Smell Villains stand for
F - fibrous layer of pericardium
P - parietal layer of the serous pericardium
S - serous fluid
V - visceral layer of the serous pericardium
What is the role of the pericardium
Fixes the heart
Prevents overfilling
Lubrication
Protection from infection
What is the innervation of the pericardium
Phrenic nerve
C3-C5
What is a common source of referred pain and why
Phrenic nerve
Originates in the neck and travels down the thoracic cavity
What are valves composed of
Connective tissue
Endocardium
What are the two atrioventricular valves
Tricuspid valve
Mitral (bicuspid) valve
Where are the atrioventricular valves located
Between the atria and ventricle
What are the examples of the semilunar valves
Pulmonary valve
Aortic valve
Where are the semilunar valves located
Between the ventricles and corresponding artery
Are the atrioventricular valves open or close during the start of ventricular contraction (systole)
Close
What is systole
Ventricular contraction
Where is the tricuspid valve located
Between the right atrium and right ventricle
Where is the mitral valve located
Left atrium and left ventricle
How many papillary muscles are there in total
5
How many papillary muscles are there in the right ventricle
3
How many papillary muscles are there in the left ventricle
2
When do semilunar valves close
Beginning of ventricular relaxation (diastole)
What is diastole
Ventricular relaxation
What produces the first heart sound
Close of the AV valves
What produces the second heart sound
Closing of the semilunar valves
Where is the pulmonary valve located
Between the right ventricle and pulmonary trunk
Where is the aortic valve located
Between the left ventricle and ascending aorta