anatomy of heart, pericardium and thorax Flashcards
label this diagram of the lungs, heart and great vessels
A - Right lung (Middle lobe of the right lung)
B - Right atrium of the heart
C - Right ventricle of the heart
D - Left lung (Superior lobe of the left lung)
E - Pulmonary trunk
F - Aorta (arch of the aorta)
which structures make up the inferior border of the heart?
LV, RV
which structures make up the superior border of the heart?
R and L atria, the great vessels (pulmonary artery, SVC and aorta)
which structures make up the left border?
LV, pulmonary artery
which structures make up the right border?
RA, SVC, IVC
identify the surfaces of the heart
A - Anterior surface
B - Left pulmonary surface
C - Diaphragmatic surface
D - Right pulmonary surface
E - Base
define pericardium
a membrane that covers the heart, consisting of 2 layers
- An outer fibrous layer
- An inner thin serous layer that reflects from the inside of the fibrous sac onto the surface of the heart (double layered)
describe the fibrous layer
- Outer layer of the pericardium
- Continuous with great vessels adventitia
- Rigid structure
- Prevents overfilling of the heart
describe the serous layer
Contained within the fibrous pericardial sac
Analogous to pleural membrane
Double layer
- Visceral layer (epicardium) - the inner layer of the serous pericardium
- Parietal layer - the outer layer of the serous pericardium
Between the double layer is a lubricating fluid which reduces the friction caused when the heart contracts
identify relevant structures in the image
1 Costodiaphragmatic recess
2 Diaphragm
3 Fibrous pericardium
4 Inferior lobe of left lung
5 Inferior lobe of right lung
6 Intercostal muscles
7 Line of anterior reflection of left pleura
8 Line of anterior reflection of right pleura
9 Middle lobe of right lung
10 Oblique fissure of left lung
11 Oblique fissure of right lung
12 Parietal pericardium
13 Parietal diaphragmatic pleura
14 Sternocleidomastoid
15 Second rib
16 Seventh rib
17 Superior lobe of left lung
18 Superior lobe of right lung
19 Thymic remnants
20 Transverse fissure of right lung
21 Visceral pericardium overlying myocardium
22 Visceral pleura
define pericarditis
inflammation of the pericardium, usually caused by a viral infection
define cardiac tamponade
acute pericardial effusion (fluid in the pericardial cavity)
how are pericardial sinuses formed?
when serous pericardium meets the great vessels, it reflects off and fuses with pericardium on other side, forming blind-ended spaces called pericardial sinuses
where is the transverse pericardial sinus?
posterior to aorta and pulmonary trunk
bounded superiorly by reflection of serous pericardium onto pulmonary arteries and inferiorly by reflection onto the upper pulmonary veins
under aortic arch
where is the oblique pericardial sinus?
posterior to the heart
mainly between posterior aspect of LV and the pericardial sac
name the two pericardial sinuses
transverse
oblique
label this diagram with the layer of the pericardium
A - Fibrous pericardium
B - Parietal layer of serous pericardium
C - Visceral layer of serous pericardium
label this diagram (hint: includes sinuses)
A - Oblique sinus
B - Inferior vena cava
C - Pulmonary veins
D - Right pulmonary artery
E - Transverse sinus
F - Superior vena cava
G - Aortic arch
H - Left pulmonary artery
label this diagram of heart (includes sulcus)
A - Anterior interventricular sulcus
B - Coronary sulcus
C - Apex
D - Inferior vena cava
E - Right ventricle
F - Right auricle
G - Ascending aorta
H - Superior vena cava
I - Aortic arch
J - Pulmonary trunk
K - Left auricle
L - Left ventricle
identify the structures on this cadaveric image of a heart
A - Right auricle
B - Right ventricle
C - Apex
D - Left ventricle
E - Pulmonary trunk
F - Aorta
G - Superior vena cava
H - Left pulmonary vein
I - Left auricle
what are the functions of the pericardium?
- Fixes heart in mediastinum
- Prevents overfilling of heart
- Provides lubrication, reducing friction when the heart is pumping
- Protection from infection
describe the route of blood flow through the heart
- Deoxy blood from inferior and superior parts of body travels through SVC AND IVC respectively into RA
- RA fills with deoxy blood
- Blood flow from RA into RV via tricuspid valve (AV valve)
- RV fills with deoxy blood
- Blood flows from RV into pulmonary trunk via pulmonary valve (semi-lunar valve)
- Pulmonary trunk splits into L and R pulmonary arteries. Blood flows through these to lungs to be oxygenated
- Once oxygenated, blood flows through pulmonary veins into LA
- LA fills w oxy blood
- Blood flows from LA into LV via bicuspid (mitral valve)
- LV fills with oxy blood
- Blood flows from LV into aorta via aortic valve
- Aorta becomes aortic arch where it gives off three main branches to superior body tissues and descending aorta supplies the inferior body tissues
which vessels return blood to the right atrium?
SVC and IVC
describe the atrioventricular orifice (right)
aperture in which blood slows from RA to RV where the tricuspid valve is positioned
describe the AV node
the electrical relay station between the atria and ventricles
located in posteroinferior region of interatrial septum near the opening of the coronary sinus
(RA feature)
describe the coronary sinus orifice
where most venous draining of the heart is returned to the heart’s circulation
located anteromedially
describe the crista terminalis
meaning: terminal crest
origin of pectinate muscles
sulcus terminalis acts as surface marking for internal crista terminalis
(RA feature)
name major features of the RA
- AV orifice (right)
- AV node
- coronary sinus orifice
- crista terminalis
- eustachian valve
- fossa ovalis
- interatrial septum
- pectinate muscles
- right auricle
- SA node
- sulcus terminalis
- thebesian valve
describe the eustachian valve
valve of inferior cava
describe the fossa ovalis
depression in the RA at the level of the interatrial septum (the wall between RA and LA)
embryological remnants of oval septal defect - foramen ovale
describe the interatrial septum
fibromuscular wall between LA and RA
describe the pectinate muscles
parallel ridges located in walls of atria
meaning: comb-like
describe the left/right auricle
muscular pouch that acts to increase capacity of the atrum
aka the right atrial appendage
describe the SA node
pacemaker of the heart
located in posterior wall of RA, inferolateral to opening of SVC, along the superior part of the crista terminalis
describe the sulcus terminalis
shallow depression marking point of fusion between venous part of the RA and the true RA
describe the thebesian valve
valve of the coronary sinus
(RA feature)
describe the chordinae tendineae
attach to cusps of AV valves and papillary muscles found in ventricles
act to secure the valves in place
describe the conus arteriosus
anterosuperior portion of the RV of the heart from which the pulmonary trunk arises
describe the interventricular groove
the groove positioned on the external surface which marks the separation between the two ventricles
list the major features of the RV
- Papillary muscle
- Trabeculae carneae
- AV orifice (right)
- Chordae tendineae
- Conus arteriosus
- Interventricular groove
- Interventricular septum
- Moderator band
- Pulmonary valve
describe the interventricular septum
fibromuscular wall between LV and RV
describe the moderator band
thick muscular strcutures which arises from interventricular septum and ends at the anterior papillaru muscles in the RV
acts as a shortcut for right AV bundle tract
describe the papillary muscles
attached to the chordae tendinae which act to prevent the prolapse of the AV valves
in the RV, there is an anterior, posterior and septal papillary muscle
in the LV, there is an anterior and posterior
describe the pulmonary valve
valve between RV and the pulmonary trunk
describe the trabeculae carnae
irregular muscular columns found on internal surface of the ventricles of the heart
which vessels return oxy blood to the LA?
pulmonary veins
describe the AV orifice (left)
aperture in which blood flows from LA to LV
bicuspid valve positioned here
describe the aortic valve
valve between aorta and LV
identify the structures on this diagram of the RA
label this diagram of the ventricles
A - Bicuspid (mitral) atrioventricular valve
B - Chordae tendinae
C - Papillary muscle(s)
D - Trabeculae carneae
name the 2 types of valves in the heart
atrioventricular valves and the semilunar valves
what are the two types of AV valves?
bicuspid (mitral) valve = between LA and LV
tricuspid valve = between RA and RV
when do AV valves close?
start of ventricular systole, allowing blood to flow into the arteries and not back into the atria
what are the two types of semilunar valves?
aortic valve = between LV and aorta
pulmonary valve = between RV and pulmonary trunk
what is the function of semilunar valves?
stop blood flowing back into the ventricls during ventricular diastole
how do valves cause heart sounds and which valves produce them?
closing of the valves causes heart sounds
1st heard sound ‘lub’ = closing of AV valves
2nd heart sound ‘dub’ = closing of semilunar valves
what is the sequence of the conducting system?
- An excitation signal is produced by the sinoatrial (SA) node - Tte pacemaker of the heart
- This signal spreads across the atria, causing them to contract.
- The signal is delayed at the atrioventricular (AV) node as their are less gap junctions between cells on the approach. This is to ensure the atria have enough time to pump the blood into the ventricles before contraction.
- The signal is then conducted into the atrioventricular bundle (bundle of His), down the interventricular septum in left and right bundle branches.
- The bundle branches and the Purkinje fibres transmit the signal along the ventricle walls, causing them to contract.
describe the fibrous skeleton
acts as electrical insulator between atria and ventricles
helps with the delay at the AV node
identify the key components of the conduction system in this diagram
A - Sinoatrial node
B - Atrioventricular node
C - Septomarginal trabeculae (Moderator band)
D - Papillary muscle
E - Atrioventricular bundle (of His)
F - Interventricular septum
G - Purkinje fibres
define coronary circulation
the blood supply to the heart
what is the SA nodal artery a branch of?
RCA (60%)
LCA (40%)
what is the posterior interventricular vein/posterior descending artery a branch of?
RCA (70%) - right dominance
LCA (10%) - left dominance
both (20%) - co-dominance
define cardiac dominance
the vessel which gives rise to the posterior interventricular artery/posterior descending artery
label this diagram of the coronary arteries
label this diagram of the cardiac veins
label the colours of the diagram with which vessel supplies it
describe the intrinsic conducting system
Intrinsic conducting system = within heart
Made up of specialised cardiac muscle cells – not nervous tissues
describe the extrinsic conducting system
Extrinsic conducting system = controlled by nerves
Controls heart rate, contraction force
describe the components of the extrinsic conducting system
- Parasympathetic innervation = vagus nerve (C10) - inhibits heart beat
- Sympathetic innervation = sympathetic trunk - stimulates heart beat
- Cardiac plexus (superficial and deep) = network of parasympathetic and sympathetic nerves
list the components of the intrinsic conducting system
- SA node
- AV node – close to coronary sinus and tricuspid valve
- AV bundle (bundle of His) - membranous part intraventricular septum
- Purkinje fibres
- Papillary muscles
- Right bundle branch
- Moderator band – shortcut to anterior papillary muscle
define angiogram
type of x-ray which uses a contrast dye in order to visualise blood vessels
what is the clinical significance of cardiac dominance?
- implant planning for operations
- people with left dominance can be at more risk of some heart problems
what does the RCA supply?
- RA
- bit of RV
- SA node
- AV node
which chambers does the left marginal coronary artery supply?
LV
which chambers does the right marginal coronary artery supply?
RV
which chambers does the left anterior descending coronary artery supply?
- mostly RV
- bit of LV
which chambers does the circumflex supply?
- LA
- bit of LV
which chambers does the posterior interventricular artery (aka post descending artery) supply?
bit of both ventricles
where does the coronary sinus drain into?
vena cava
list the cardiac veins
- Anterior interventricular veins
- Great cardiac vein
- Posterior cardiac vein
- Middle cardiac vein
- Small cardiac vein
- Coronary sinus
identify the structures by the surface anatomy
A - Clavicle
B - Jugular notch
C - Manubrium of the sternum
D - Sternal angle
E - Sternal body
F - Xiphoid process
G - Costal margin
H - Costal cartilage
I - Ribs
