Anatomy of the heart Flashcards
where do the phrenic nerves originate from?
the neck
where do the phrenic nerves pass down to eventually reach?
pass down between the lungs and heart to reach the diaphragm
what is the phrenic nerve innervation (e.g. C…)?
C3-5
where would you anatomically find the phrenic nerves?
descending across the lateral borders of the pericardium
what are the 3 membranous layers that encircle the heart in the pericardium called?
1) fibrous
2) parietal
3) visceral
what can the visceral layer also be called?
the inner epicardium
what is the name given when the parietal and visceral pericardium join together?
the serous pericardium
what is the layer of the pericardium that is the outmost layer?
fibrous
what is the layer of the pericardium that is the middle layer?
parietal
what is the layer of the pericardium that is the innermost layer?
visceral
what is the pericardial cavity?
the potential space formed between the two layers of serous pericardium
what is the term given if this pericardial cavity fills with blood?
Haemo-pericardium
what is cardiac tamponade?
a condition where the pericardial cavity fills with blood therefore increasing the pressure around the heart so much so that it PREVENTS CARDIAC CONTRACTION
what is pericardiocentesis?
drainage of fluid from the pericardial cavity
where is the pericardiocentesis needle placed?
- instead via infra-sternal angle, directed super-posteiorly
- another location is through the 5th or 6th intercostal space at the left sternal border at the cardiac notch of the left lung
what is the transverse pericardial sinus?
= a space within the pericardial cavity, posterosuperiorly
where does this transverse pericardial sits lie?
what does it allow cardiac surgeons to identify & isolate?
Name the 5 great vessels,
lies POSTERIOR to the ascending aorta & pulmonary trunk
Identify & isolate great vessels allowing cardiopulmonary bypass.
Great vessels;
- aorta
- SVC
- IVC
- pulmonary artery
- pulmonary vein
as the surgeons fingertip emerges from the sinus where is it near to?
it is anterior to the SVC
what are the 3 surfaces of the heart?
1) anterior (sternocostal) surface
2) base (posterior) surface
3) inferior (diaphragmatic) surface
what are the 4 borders of the heart?
1) right (lateral) border
2) left (lateral) border
3) inferior border
4) superior border
what side is the important apex usually on?
the LEFT SIDE
where is the apex located?
the 5th left intercostal space in the mid-clavicular line (mitral area)
what is special about this apex?
you can palate it
the the heat undergoes cardiac enlargement, where does it often shift the apex to?
to the left
what does the azygous vein do?
drain the intercostal space
what do coronary arteries & their branches do?
they are the arterial blood supply to the epicardium & myocardium
where do the coronary arteries arise from?
arise from the ascending aorta.
what is the first branch of the aorta?
the coronary artery
what are the 2 main branches of the coronary artery?
1) left
2) right
what are the 2 branches of the right branch of the coronary artery?
1) right marginal artery
2) posterior inter-ventricular artery
what does the right marginal artery supply?
supplies the right ventricle
what is the posterior inter-ventricular artery?
a continuation of the right coronary artery, it hooks round the back of the heart
why is the left branch of the coronary artery much shorter than the right?
as the left branches almost immediately
what are the 4 branches of the left branch of the coronary artery?
1) circumflex artery
2) left anterior descending (LAD) - anterior inter-ventricular artery
3) left marginal artery
4) lateral (diagonal) branch
what does the circumflex artery join with?
joins with the posterior inter ventricular artery (for the right side)
what is the coronary sinus?
a short venous conduit (in the atrioventricular groove posteriorly) which receives deoxygenated blood from most of the cardiac veins & drains into the right atrium
what is a simplified explanation of the coronary sinus?
the big vein that receives all the smaller veins
what separates the atria of the heart from the ventricles?
the coronary grooves / coronary sulcus
what is the function of the septum?
an internal wall that divides the heart into a right & left side
what are the 2 parts to the septum?
1) inter-atrial septum
2) inter-ventricle septum
what does the inter-atrial septum do?
separates the two atrial (i.e. the right from the left)
what does the inter-ventricular septum do?
separates the two ventricles (i.e. the right from the left)
what would you call the defect if there is is a “hole” in the inter-atrial septum?
an atrial septal defect
what would you call the defect if there is a “hole”. I the inter-ventricular septum?
a ventricular septal defect
what can a septal defect cause?
hypoxaemia
how can a septal defect cause hypoxaemia?
- a septal defect means that there is the mixing of material & venous blood
- therefore reducing the oxygen content of systemic atrial blood in the aorta
the right atrium has 3 openings, what are they are?
1) superior vena cava
2) inferior vena cava
3) coronary sinus
what separates the rough and smooth part of the right atrium?
= crista termanalis
how does the heart ensure that blood flow is uni-directional?
presence of valves
what are the 4 valves?
1) pulmonary
2) aortic
3) mitral
4) tricuspid
where is the tricuspid valve found?
between right atrium & night ventricle
where is the mitral (bicuspid) true found?
between left atrium & left ventricle
where is the aortic valve found?
between left ventricle & aorta
where is the pulmonary valve found?
between right ventricle & pulmonary trunk
where do each of the vales exit from?
each valve exists from each cardiac chamber
what are the 3 cusps of the tricuspid valve?
1) anterior
2) posterior
3) septal cusps
what are the 2 cusps of the mitral valve?
1) anterior
2) posterior
what are the 3 cusps of the pulmonary valve?
1) anterior cusps
2) right cusp
3) left cusp
what are the 3 cusps of the aortic valve?
1) posterior cusps
2) right cusps
3) left cusps
when is the first heart sound heart?
when the tricuspid & mitral valves close simultaneously
when is the second heart sound heart?
when the pulmonary & aortic valves close
where does the coronary arteries arise from?
the right & left aortic sinuses
what 2 things prevent prolapse of valves during ventricular contraction?
1) tendinous cords
2) papillary muscles
what does the fibrous skeletal of the heart do?
facilities electrical distribution of the heart to the valves
what does the moderator band do?
also known as the septomarginal trabecular do?
= carries fibres of right bundle branch to the papillary muscle of the anterior cusp
what are the anatomical positions of the 4 cardiac valves called?
open ellipses
describe the 4 places where you can auscultate to find the 4 valves.
1) Aortic = 2nd right intercostal sternal edge
2) tricuspid = 4th left intercostal sternal edge
3) Pulmonary = 2nd left intercostal sternal edge
4) Mitral = 5th left intercostal, mid-clavicular line
