B2 Anatomy of the Heart Flashcards
Where is the heart in the body?
Thorax
How big is the heart?
In adulthood about the size of one’s own fist
Where does the apex of the heart point towards?
Left nipple
Where is the right side of the heart located?
between third and sixth costal cartilages (at sternal angles)
Where is the apex of the heart located?
5th intercostal space, mid clavicular line
What fraction of the heart is on the left side of the heart?
2/3
Which vertebra does the heart start on?
T5
Which vertebra does the heart end at?
T8
What is the the heart tissue known as?
Pericardium
What is serous pericardium made from?
Parietal pericardium
Visceral pericardium
What is the heart muscle actually made from?
Visceral pericardium
Myocardium
Endocardium
Where is fibrous pericardium?
The outermost layer of the pericardium
What is between the visceral and parietal pericardium?
Pericardial cavity
Where is the endocardium?
Lining the ventricles and atria
What type of cavity is the pericardial cavity?
A potential space
What is the appearance of parietal pericardium?
Shiny
What is the posterior surface of the heart in its anatomical position?
Left atrium
What part of the heart forms the apex?
Left ventricle
What is the part of the heart in contact with the sternal surface?
Left ventricle
What is the part of the heart in contact with the diaphragm?
Left ventricle/ Right ventricle
What is the surface in contact with the diaphragm known as?
Diaphragmatic surface
What is the surface in contact with the left lung known as?
Left pulmonary border
What is the right border of the heart?
Right atrium and superior vena cava
What is the left border of the heart?
Left ventricle
Left auricle
Pulmonary trunk
Aortic arch
Why is knowing the radiological borders of the heart important?
You’ll be able to know the locations of pathology when the border gets distorted
What are the purposes of the atria?
To fill the ventricles
To set the cardiac pace
What is the pace of the atria contracting?
> 60bpm
What is the sinus venarum?
The smooth area of the right atrium
What is the musculi pectini
The rough area of the right atrium
What is the sulcus terminalis?
The groove on the outside of the heart which marks the location of the SAN
What is the crista terminalis?
A ridge on the inside of the heart that separates the smooth area from the rough area and contains the SAN
What is the fossa ovalis?
A hole in the septum of the heart in fetal circulation
Where would you find the septum of the heart?
Between the left and right sides of the heart
True or false? The left atrium forms one of the borders of the heart?
False
Is the left side of the heart thicker than the right side of the heart?
Yes
Why is one side of the heart thicker than the other?
To pump over greater area and against gravity.
Without the SAN, how quickly can the ventricles pump?
Maximum 40bpm
What are trabeculae carnae?
‘ridges of meat’; lumps all over the place
What are cordae tendinae?
Tendinous cords
Where are trabeculae carnae?
Right ventricle
Where are cordae tendinae?
Right ventricle
What is the function of cordae tendinae?
Stops backflow of blood by holding valves down.
What are papillary muscles?
Muscles in the right ventricle of the heart
Why are papillary muscles important?
Contracts to close valves by pulling on the cusps
What is the trabeculum septomarginalis?
A moderator band that the right bundle of His travels through
What is the infundibulum?
Smooth funnel-like pathway leading to the pulmonary artery in the right ventricle
Which of the two ventricles does the septum project into?
The right ventricle
What does papillary muscle infarction result in?
Regurgitation/ ejection at the point when ventricular pressure is greater than the cordae tendinae can control
What is the only valve that isn’t tricuspid?
Left AV - Mitral
What plane do all of the cardiac valves roughly lie in?
Almost sagittal plane behind sternum
Why can’t you directly auscultate the valves?
- They’re behind the sternum
- Chamber into which the valve opens is closer than the valves
- Better and easier to distinguish the sounds by auscultating the direction of flow.
What is the direction of flow across the aortic valve?
Superior and lateral to the valve - left side of sternum
What is the direction of flow across the pulmonary valve?
Superior but contralateral to the aortic valve
What is the direction of flow across the tricuspid valve?
Towards the apex of the heart
What is the direction of flow across the mitral valve?
At the apex of the heart
How can you determine pathology though auscultation?
The auscultatory regions will move if affected by something
Where do the heart’s sinuses drain into?
Coronary arteries
Where is the right coronary artery in relation to the sinus?
Comes off the anterior sinus
Where is the left coronary artery in relation to the sinus?
Comes off the posterior sinus
What are the correct names for the sinuses?
One anterior; two posterior
Are there left, right and posterior sinuses?
No - these are incorrect anatomically
What is special about coronary artery filling?
They only fill when valves are closed and blood rushes back from the aorta to fill them (diastole) - don’t fill when the heart ejects its blood
Why do coronary arteries fill weirdly?
- They are not positioned where the flow of blood would be in systole.
- The pressure is too high for there to be enough blood filling for them
When the heart muscle is contracting, what happens to the capillary bed?
It closes off
Where can you find coronary arteries?
Next to the coronary sinuses
On the surface of the heart
What is the purpose of the coronary arteries?
They supply the heart muscle
How do the coronary sinuses distribute supplying and draining the heart?
They equally supply and drain the heart
Where is the coronary sinus?
the coronary groove between the left atrium and left ventricle.
Where does the coronary sinus drain into?
The coronary sinus opens into the right atrium between the openings of the inferior vena cava and the tricuspid valve
What is the obtuse marginal artery?
A branch of the left circumflex artery which travels towards the apex of the heart
What are the accompaniments to coronary arteries?
Cardiac veins
What are the different cardiac veins?
Great
Middle
Small
What does the great cardiac vein accompany?
Anterior interventricular artery
What does the middle cardiac vein accompany?
Posterior interventricular artery
What does the small vein accompany?
Marginal artery
Where do oblique veins come off of?
Left atrium
Where do veins (exc. veni cordis minimi) drain blood?
Into the coronary sinus which drains into the right atrium
Where do veni cordis minimi drain into?
The chamber nearest to them
What is the average heart rate of an adult?
72bpm