Heart Flashcards
What is gastrulation?
Formation of the three layers, ectoderm, mesoderm, endoderm
Which layer ( endoderm, ectoderm, mesoderm) does the majority of the cardiovascular system come from?
Mesoderm
What does the first heart field develop into?
The left ventricle
Which heart field do the atria and the right ventricle arise from?
The second heart field
What are the three stages of heart formation?
- Formation of the primitive heart tube
- Cardiac looping
- Cardiac septation
The cardiogenic region forms in which week of development?
Third week
What two tubes have developed by day 19 that fuse to form the single primitive heart tube?
Endocardial tubes
What do the endocardial tubes fuse to from?
The heart tube
What part of the heart tube forms the right ventricle and parts of the outflow tracts for the aorta and pulmonary trunk?
bulbis cordis
In the heart tube, what does the bulbis cordis sit superiorly to?
The primitive ventricle
What does the primitive ventricle of the heart tube form?
The left ventricle
What does the primitive atrium sit inferiorly to in the heart tube?
The primitive ventricle
What part of the heart tube forms the vena cava?
The sinus venosus
Describe the movement of the primitive atrium and the sinus venosus in cardiac looping
move superiorly and posteriorly
Where does the primitive ventricle move during cardiac looping?
To the left
Describe the movement of the bulbis cordis during cardiac looping
Moves inferioly, anteriorly and to the right
What are the common atrium and ventricle connected by before cardiac septation?
The atrioventricular canal
Describe the circulation after cardiac looping and before cardiac septation
Blood enters the atrium, passes through the AV canal, passes into the ventricle, blood exits the heart via the truncus arteriosus
What grows at the sides of the AV canal to form right and left AV canal?
Endocardial cushions
Where can you find the apex beat?
Left 5th intercostal space, mid clavicular line
What forms the right heart border?
Atrium and superior vena cava
What is the heart mainly anteriorly?
Right ventricle
What is the heart mainly posteriorly?
Left atrium
What does the mediastinum lie between?
right and left pleura
What does the plane that divides the mediastnum into superior and inferior lie between?
The sternal angle and T4/5
Where is the sternal angle?
Where body and manubrium of sternum articulate
Describe the layers of the pericardium
Fibrous-outer layer
Serous- inner layer
What layers can the serous pericardium be divided into?
Visceral and parietal
What side of the heart is the mitral valve on?
left
What side of the heart is the tricuspid valve on?
right
What are the two semilunar valves called?
aortic valve and pulmonary valve
How many cusps does the mitral valve have?
two
What are the chordae tendinae attatched to?
At one end- either the mitral or tricuspid valve
At the other end- the papillary muscles
Define arterial blood
Blood leaving the heart
Define venous blood
Blood returning to the heart
what kind of blood does the pulmonary artery carry?
Deoxygenated blood
What kind of blood does the pulmonary vein carry?
Oxygenated blood
Which ventricle has a thicker wall?
left
how many pulmonary veins usually drain into the left atrium?
4
What are heart muscle cells called?
cardiomyocytes
Where do the right and left coronary arteries originate?
The base of the aorta
What are the two major branches of the left coronary artery?
Left anterior descending artery
Circumflex artery
What are the two major branches of the right coronary artery (usually! Remember one can branch off the left coronary artery but this is less common)
The posterior descending artery
The right marginal artery
What does it mean if someone has right dominant circulation?
Their posterior descending artery branches off from the right coronary artery
What does it mean if someone has left dominant coronary circulation?
Their posterior descending artery branches off the circumflex artery
How would you describe the coronary circulation of someone who’s posterior descending artery is supplied by both their right coronary artery and their circumflex artery?
Codominant
Where does the coronary sinus empty into?
The right atrium
What vein does blood the myocardium supplied by the LAD empty into?
the great cardiac vein
What vein does blood from the myocardium supplied by the circumflex artery empty into?
The posterior vein of the left ventricle
What vein does blood from the myocardium supplied by then marginal artery empty into?
The small cardiac vein
The myocardium that’s blood drains into the middle cardiac vein is supplied by which artery?
The posterior descending artery
At what stage in the cardiac cycle does the myocardium receive blood?
diastole
Where in the heart will you find the fossa ovalis?
The right atrium
What did the fossa ovalis used to be in the fetus?
The foramen ovale
Where in the heart will you find the SA node?
The right atrium
What are the collagen cords called that attatch valves to papillary muscles?
Chordae tendinae
What does the pulmonary trunk split into
left and right pulmonary arteries
What branch of the aorta gives rise to the right common carotid and the right subclavian artery?
Brachiocephalic artery
List the layers of the heart and pericardium
Endocardium Myocardium Epicardium Pericardial cavity Parietal layer of the serous pericardium Fibrous pericardium
What can the epicardium also be called?
The visceral layer of the serous pericardium
What is the outermost layer of the pericardium?
The fibrous pericardium
What is the innermost layer of the pericardium?
Epicardium
What lies between the epicardium and the parietal layer of the serous pericardium?
The pericardial cavity
What groove does the LAD run in?
The anterior interventricular groove
What groove does the Cx run in?
The left atrioventricular groove
What is the least common coronary circulation dominance?
Left dominant
What is the most common coronary circulation dominance?
Right dominant
