Anatomy 1 Flashcards
What are hilar lymph nodes the same as?
Bronchopulmonary lymph nodes
Where do phrenic nerves descend in the thorax?
Across lateral borders of the pericardium
How are phrenic nerve and vagus nerve differentiated?
* If anterior to hilum, phrenic nerve
* If posterior to hilum, vagus nerve
What are the 2 layers of the pericardium? (2)
* Fibrous pericardium
* Serous pericardium (further split into parietal and visceral layers)
What is visceral serous pericardium also known as?
Epicardium
What does epicardium do?
Secrete pericardial fluid
What exists between the 2 pericardial layers?
Pericardial cavity filled with pericardial fluid
What is fibrous pericardium line internally by?
Parietal serous pericardium
What can cause cardiac tamponade?
Haemopericardium - when pericardial cavity fills with blood and pressure around heart prevents cardiac contraction
What is cardiac tamponade?
Pressure around heart due to accumulation of fluid in pericardial cavity that can prevent cardiac contraction
What is the treatment for cardiac tamponade?
Pericardiocentesis
What is pericardiocentesis?
Drainage of fluid from pericardial cavity
Where is the needle inserted in pericardiocentesis?
Need to aim for “bare area” of pericardium by inserting needle via infrasternal (subcostal i.e. below costal angle) angle and directing it superoposteriorly
In pericardiocentesis, how do physicians know they are in pericardial cavity?
Continually aspirating with needle until it begins to fill up with blood - that is when you are in pericardial cavity
What is transverse pericardial sinus?
A space within pericardial cavity posterosuperiorly
Where is transverse pericardial sinus located?
Posterior to ascending aorta and pulmonary trunk, in front of SVC
Why is transverse pericardial sinus clinically important?
Cardiac surgeons use sinus to identify and isolate great vessels in order to commence cardiopulmonary bypass
Label the openings of the great vessels (pic)
A - Inferior vena cava
B - Superior vena cava
C - Aorta
D - Pulmonary trunk
E - Left pulmonary artery
F - Left pulmonary veins
What are the clinically important surfaces of the heart? (3) Why are they clinically important?
* Anterior (sternocostal) surface
* Base (posterior) surface
* Inferior (diaphragmatic surface)
* Used to describe type of heart attack they may have
What mainly comprises the inferior border?
Right ventricle
What are the clinically important borders of the heart? (2)
* Right border
* Left (lateral) border
What mainly comprises the left border?
Left ventricle
What mainly comprises the right border?
Right atrium
What is another clinically important area of the heart aside from borders and surfaces?
Apex
When can left atrium be visualised?
Cannot be visualised anteriorly like right atrium, can only really be seen posteriorly
Where is the apex beat of the heart palpated?
5th left intercostal space in the midclavicular line (mitral area)
What can an apex beat that is shifted to the left signify?
Cardiomegaly (cardiac enlargement) possibly caused by heart failure
Name the labelled structures on the anterior surface of the heart (pic)
A - right coronary artery (in coronary groove)
B - Right pulmonary veins (superior and inferior)
C - Right pulmonary arteries (superior and inferior)
D - Brachiocephalic trunk
E - Right subclavian vein
F - Right subclavian artery
G - Right common carotid artery
H - Left common carotid artery
I - Left vagus nerve
J - Left subclavian artery
K - Left phrenic nerve
L - left brachiocephalic vein (BCV)
M - Left pulmonary artery
N - Left pulmonary veins
O - branch of left coronary artery (in anterior inter ventricular groove)
P - Apex
What is the coronary groove?
Boundary between right atrium and right ventricle (also surface marking for tricuspid valve)
What is the anterior inter ventricular groove?
Boundary between the 2 ventricles on anterior surface of heart
What are other names for the branch of the left coronary artery that descends over anterior surface of the heart?
* Left anterior descending artery
* Anterior inter ventricular artery
What does right coronary artery pass over anterior surface of the heart within? Branch of left coronary artery?
* Coronary groove
* Anterior inter ventricular groove
What are right and left brachiocephalic veins formed from?
Joining of right/left internal jugular and subclavian veins (tributaries)
How does oxygenated blood return to the heart?
Via right and left pulmonary veins
What does brachiocephalic trunk (NOT vein) bifurcate into?
Right common carotid and right subclavian artery
What are auricles? Function?
Extensions of the atria - allow atria to expand and fill with more blood
Name the labelled structures on the base and diaphragmatic surfaces of the heart (pic)
A - Branch of right coronary artery with posterior inter ventricular vein (in posterior interventricular groove)
B - Left pulmonary veins
C - Left pulmonary artery
D - Azygous vein
E - Right pulmonary arteries
F - Right pulmonary veins
G - Interatrial groove
What is the coronary sinus?
Short venous conduit that receives deoxygenated blood from cardiac veins and drains into RIGHT atrium
Where is coronary sinus located?
In atrioventricular groove posteriorly (separates atria and ventricles)
What is the posterior inter ventricular groove? What is located within groove?
* Boundary between 2 ventricles on diaphragmatic surface of heart
* Branch of right coronary artery (posterior inter ventricular artery) with posterior inter ventricular vein
What is the branch of the right coronary artery that passes through posterior interventricular groove known as?
Posterior interventricular artery
What do most cardiac veins drain into?
Coronary sinus
What is the function of the azygous vein?
Intercostal veins drain into azygous vein which drains into SVC
What is the function of the coronary arteries and their branches?
Arterial blood supply to epicardium and myocardium
Where do coronary arteries and their branches course?
Deep to the epicardium usually embedded in adipose tissue
Where do the coronary arteries branch from?
The ascending aorta (first branches of the aorta)
Name structures labelled on anterior surface of the heart
A - Right marginal artery
B - Right coronary artery
C - Coronary arteries arise from ascending aorta
D - Left coronary artery
E - Circumflex artery
F - Left anterior descending (LAD)/anterior interventricular artery
G - Left marginal artery
H - Lateral (diagonal) branch
I - Posterior interventricular artery
What do right and left marginal branches follow?
The margins of the heart
What artery anastomoses with right coronary artery in the atrioventricular groove?
Circumflex artery
What divides heart into a right side and left side?
Septum (internal wall)
What are the 2 parts of the septum? (2)
* Interatrial septum (between the 2 atria)
* Interventricular septum (between the 2 ventricles)
Where are the 2 parts of the septum positioned? (2)
* Interatrial septum - interatrial groove
* Interventricular septum - interventricular groove
What is an atrial septal defect (ASD)? Ventricular septal defect (VSD)?
* Hole in the interatrial septum
* Hole in the interventricular septum
Why are atrial and ventricular septal defects an issue?
Get mixing of oxygenated and deoxygenated blood so blood transported around body that isn’t fully oxygenated - HYPOXAEMIA
What does mixing of venous and arterial blood do?
Reduces oxygen content of systemic arterial blood in the aorta - HYPOXAEMIA
Name structures labelled on anterior surface of heart (pic)
A - Opening of IVC
B - Opening of coronary sinus
C - Oval fossa
D - Crista terminalis
E - Location of SA node
F - Opening of SVC
G - Muscle bands of auricle wall
H - Anterior interventricular groove
I - Coronary groove
What are the 3 openings in the right atrium?
* Superior vena cava
* Inferior vena cava
* Coronary sinus
What separates the muscular bands of the auricle wall?
Crista terminalis
What is oval fossa/fossa ovalis?
Embryological remnant of foramen ovale
How does heart ensure unidirectional flow?
4 cardiac valves (tricuspid, bicuspid (mitral), pulmonary valve and aortic valve)
What are the cusps of the pulmonary valve? Aortic valve? Tricuspid valve? Mitral valve?
* Pulmonary valve - anterior, right and left cusp
* Aortic valve - posterior, right and left cusp and sinuses
* Tricuspid valve - anterior, posterior and septal cusp
* Mitral valve - anterior and posterior cusp
What is significant about the sinuses (spaces within cusps) in aortic valve?
Coronary arteries arise from the right & left aortic sinuses respectively
What is the design of pulmonary and aortic valves? Tricuspid and mitral valves?
* Semilunar design
* Leaflet design
What are leaflets of tricuspid and mitral valves connected to?
Connected to papillary muscles (cardiac muscle attached to chamber walls) via tendinous chords
Why is leaflet attachment to papillary muscles important?
To prevent reflux of of leaflets during ventricular contraction
What is the function of the cardiac skeleton? (2)
* Gives valves structural integrity, anchor and structure
* Assists electrical conduction through heart
What valves are surrounded by fibrous cardiac skeleton?
…?????
What is the moderator band? Function?
* Moderator band (septomarginal trabecula) is muscular band of heart tissue found in right ventricle of the heart
* Shortcut for electrical activity reaching anterior cusps of tricuspid valve (need shortcut cause anterior cusp is further away from other 2 cusps but still has to contract at same time as other 2)
Name structures in interior of left atrium (and 1 structure on posterior surface on heart)
A - Interatrial groove
B - Cusps of mitral valve
C - Remains of foramen ovale (oval fossa)
D - bilateral openings of superior and inferior pulmonary veins
E - left auricle
What are the positions for auscultation of the heart valves?
* Aortic - 2nd ICS, right sternal edge
* Pulmonary - 2nd ICS, left sternal edge
* Tricuspid - 4th ICS, left sternal edge
* Mitral - 5th left ICS, mid-clavicular line
DO NOT GET CONFUSED WITH PRECORDIAL ECG POSITIONS
What is the purpose of auscultating heart valves?
Listening for heart sounds and murmurs
