HEART Flashcards
SURFACES
anterior, posterior, inferior, apex
Anterior Surface
made by R Atrium, R Vent, L Vent, ant. I/V groove
Posterior Surface
made mostly by L Atrium
Posterior Surface
made mostly by L Atrium
Inferior Surface
made mostly by L Vent
- others are post I/V groove, (R atrium + vent)
Apex surface
made by L Vent
BORDERS
Right (lateral), Left (lateral), inferior, superior
Right (lateral) border
made by R Atrium
Right (lateral) border is found in area between…
SVC + IVC; 3rd to 6th ribs
Left (lateral) border
made by L Vent (+L atrium)
Left (lateral) border is found
5th rib (apex) to 2nd rib
Inferior border
made by R Vent
Inferior boarder is found
along 5th I/C space
Superior boarder is found
2nd rib
Superior border
made by roots of Aorta/Pulmonary Artery/SVC
Coronary Sulus
groove between the atria (superiorly) and ventricles (inferiorly)
-runs completely around the heart
Anterior Interventricular Groove
on anterior surface of heart, shallow groove between R and L ventricles
Anterior Interventricular Groove contains…
Anterior Interventricular Artery
Posterior Interventricular Groove
on posterior surface of heart, shallow groove between R and L ventricles
Posterior Interventricular Groove contains…
Posterior Interventricular Artery
major vein draining blood from all structures below the diaphragm into the R atrium
Inferior Vena Cava
major vein draining blood from head and upper limbs to R atrium
Superior Vena Cava
Major vessels on right superior aspect of heart
IVC + SVC
major artery delivering blood to all regions of body
Aorta
curved portion of aorta arching from anterior to posterior
Aortic arch
Part of artery that is short and immediately off of heart
Ascending Aorta
Part of aorta running posteriorly through thoracic cage along the vertebral column to diaphragm
Descending Aorta
Pulmonary Artery (trunk)
adjacent to L of aorta, splits into R and L pulmonary arteries under arch of aorta
Pulmonary Artery splits into…
R and L pulmonary arteries under arch of aorta
Pulmonary Veins
usually 4 on posterior surface of heart
- 2 opening on R side of L atrium
- 2 openings on L side of L atrium
may be variations
“1st part of heart”, takes deoxygenated blood from body and moves to R vent
Right atrium
Right atrium
“1st part of heart”, takes deoxygenated blood from body and moves to R vent
“ear-shaped” appendage on R atrium, located on anterior-superior aspect of the R atrium
- also one on L atrium
Auricle
Where is IVC opening found?
on R atrium at inferior aspect of chamber
Where is SVC opening found?
on R atrium at superior aspect of chamber
Where is opening of Coronary Sinus found?
on R atrium, on inferior aspect of chamber near opening of IVC
Where is the SA Node found?
on R atrium anteriorly, at border between SVC and R atrium
Where is AV Node found?
on R atrium in interatrial septum near the atrioventricular orifice
Pectinate muscles
contractile muscles on internal surface of L and R atrium
Contractile muscles of atriums
pectinate muscles
Fossa Ovalis
on R atrium depression in center of interatrial septum (varies in size) - between L and R atrium
Tricuspid Valve Leaflets
3 leaflets, separating R atrium from R ventricle
multiple thin CT cords attaching leaflets to papillary muscles
Chordae Tendinae
Where are chordal tendinae found?
in L and R ventricles
Where are papillary muscles found?
in L (2) and R (3) ventricles
Role of papillary muscles
Contract to pull chordae tendinae, keeping valve leaflets from prolapsing (flipping backwards) into R atrium when ventricle contracts
- Prevents blood from regurgitating into R atrium
What prevents blood from regurgitating into atrium?
Papillary Muscles
contractile muscle of ventricle
Trabecular muscle
smooth funnel-shaped region of the R ventricle leading to pulmonary valve
Conus Arteriosus
Where is the Moderator Band found?
R ventricle
Moderator Band
small band of specialized muscle tissue in inferior aspect of R ventricular chamber
Moderator band runs…
from interventricular septum to inferior-lateral border of R ventricle
Pulmonary Valve
3 leaflet valve separating R ventricle from pulmonary artery
Does R or L ventricle have a thicker wall?
L
Mitral Valve
2 leaflets, separating L atrium from L ventricle
Are papillary muscles larger in L or R ventricle?
L
very short (~1-2cm) vessel, immediately off ascending aorta
Left Coronary Artery
vessel off L coronary artery, running in the anterior interventricular groove
Anterior Interventricular Artery (LAD – Left Anterior Descending)
Where does the Anterior Interventricular Artery (LAD) run?
in anterior inter ventricular groove
vessel off L coronary artery, running in coronary sulcus to L, wrapping around posterior of heart
Circumflex Artery
vessel off circumflex artery, runs along left border of heart
Left Marginal Artery
vessel immediately off ascending aorta, runs in coronary sulcus to R, wrapping around posterior of heart
Right Coronary Artery
vessel that comes off R coronary, ~1-2cm from aorta, runs between aorta/auricle of R atrium as travels to area S-A node
Sino-Atrial Nodal Artery
vessel off R coronary artery, branches off at inferior border of heart, runs along inferior border
Right Marginal Artery
vessel off R coronary in most people, runs in posterior interventricular groove on posterior surface of heart
Posterior Interventricular Artery
major vein that drains all venous blood of heart back to R atrium
Coronary Sinus
Location of coronary Sinus
in coronary sulcus starting on L side of heart
takes deoxygenated blood from lower limbs to send up to R atrium
R atrium - Opening from IVC
ant and to L of IVC opening, deoxygenated blood from draining back to R atrium
R atrium - Opening of coronary sinus
ln inter-atrial septum, shunt that is closed off at birth
R atrium - Fossa Ovalis
In Right atrium and contains Tricuspid Valve
R Atrioventricular Orifice
superior to coronary sinus opening adjacent to A-V orifice, part of electrical conduction system
A-V Node
at junction of SVC with R Atrium (anterolaterally), where electrical conduction system begins - “pacemaker”
R atrium - S-A Node
“Pacemaker of heart”
SA Node
Where does electrical conduction system of heart begin?
SA Node
smooth muscles of heart with irregular appearance that create “squeezing” action of heart
Pectinate Muscles
Function of auricle
increases volume capacity of atrium and has some contractile properties
wavy (irregular shape) for squeezing function of heart, on inner aspect of ventricle
Trabecular Muscle
attach leaflet to papillary muscle
Chordae Tendinae
How many valve leaflets are there on the R side?
3
How many valve leaflets are there on the L side?
2
smooth, funnel-shaped region leading to pulmonary artery, funnels blood towards lungs to be oxygenated
Infundibulum (conus arteriosus)
What allows coordinated contraction of ventricular wall and papillary muscles?
Moderator band (septomarginal trabecula)
How many pulmonary vein openings are there?
4
What brings blood from lungs back into L atrium?
Pulmonary Vein Openings on L atrium
opening to L vent, contains Mitral (Bicuspid Valve)
Left Atrioventricular Orifice
Why is the wall of left ventricle thicker?
increased pressure (resistance to flow)
Why are papillary muscles larger on left ventricle?
larger to withstand larger contractile forces (L vent has to pump against greater resistance)
Where does the mitral valve sit?
lateral to (or L of) Aortic Valve
L and R Coronary Arteries arise from…
base of aorta (aortic valve)
Where does aortic blood supply start?
at base of aortic valves
Where do L and R Coronary Arteries travel?
in coronary groove
Coronary Groove
groove between atria and ventricles
SHORT segment, ~2cm long, comes off base of aorta, splits immediately into anterior interventricular + circumflex
Left (main) Coronary Artery
Anterior Interventricular Artery (Left Anterior Descending) travels along
I/V groove to apex
Anterior Interventricular Artery supplies…
portion of R and L vents + anterior 2/3 of I/V wall containing L and R Bundle Branches
Anterior Interventricular Artery anatomoses with..
posterior I/V artery
Circumflex artery runs along…
coronary groove to posterior heart
Circumflex artery supplies…
L atrium and ventricle
Circumflex artery anastomoses with….
right coronary artery
Left Marginal Artery branches off… and runs…
branches off circumflex and runs along L border of heart
Left Marginal Artery supplies
L ventricle along L border of heart
very LONG, starts at base of aorta and goes in atrioventricular groove traveling around to posterior side of heart
Right Coronary Artery
Right Marginal Artery branches off… and runs…
branches from R coronary artery, travels along inferior border of heart towards apex
Right Marginal Artery supplies
R ventricle + part of apex – supplies R inferior border of heart
“Right Dominant Circulation”
Posterior Interventricular artery branches off R coronary artery
“Left Dominant Circulation”
Posterior Interventricular artery branches off circumflex artery
Dominance of circulation is determined by
where posterior interventricular artery comes off of
Posterior Interventricular Artery travels along…
posterior I/V groove to apex
Posterior Interventricular Artery supplies
portions of R and L vents + post 1/3 of I/V wall + AV Node
Posterior Interventricular Artery anastomoses with
anterior I/V artery
S-A Nodal Artery comes off of…
R coronary near its origin to supply S-A Node
- can come off of L coronary artery in 40% of people
Interventricular Septum
septum between R and L ventricle
Arterial supply of Interventricular Septum
- 2/3 of interventricular septum is supplied through the ANTERIOR interventricular artery
- 1/3 is supplied through POSTERIOR interventricular artery
Arterial supply of AV Node vs rest of conduction system
- Supplied primarily through POSTERIOR interventricular artery
- But rest of “conduction system” is supplied through ANTERIOR interventricular artery
Opens/drains into R atrium just anterior and to L of IVC opening, all other veins drain into this sinus
Coronary sinus
“Pacemaker” of heart - sets rhythm of heart
Sino-Atrial (S-A) Node
Function and type of muscle cells of SA Node
Specialized cardiac muscle cells that spontaneously depolarize - creates rhythm/rate
creates rhythm/rate
SA Node
Where is AV Node found?
ln atrial septum near coronary sinus opening near A-V Orifice
has automaticity, but typically slower than SA node
AV Node
Where is the AV Bundle located?
in membranous portion of I/V Septum
R and L bundles branches travel…
travel down muscular septum and through moderator band in R vent
modified cardiac muscle cells that distribute impulses through/out ventricular walls to pulmonary artery or aorta
Purkinje Fibers
Function of Purkinje Fibers
distribute impulses through/out ventricular walls to pulmonary artery or aorta
Steps of Conduction System Flow
- SA Node
- AV Node
- AV Bundle
- R and L Bundle Branches
- Purkinje Fibers
Nervous system innervating heart
autonomic - unconscious/involuntary control
How do nerve get to heart?
Cardiac Plexus
Location of Cardiac Plexus
immediately anterior to trachea
Components of Cardiac Plexus
Sympathetic and parasympathetic fibers
When the sympathetic nervous system of heart is activated it results in
increased HR, increased contractility, vasodilation of coronary aa (increase blood supply)
Where do Sympathetic nerve fibers of heart come from?
sympathetic chain that runs along vertebral column
Sympathetic Pre-ganglionic fibers come from what area of the vertebral column?
T1-T6
Sympathetic Post-ganglionic fibers come from..
superior cervical ganglia and upper thoracic paravertebral ganglia
Sympathetic Post-ganglionic fibers innervate:
S-A, A-V nodes, cardiac muscle fibers, and coronary vessels
When parasympathetic nervous system (vagus nerve) of heart is activated it results in
decreased HR, contractility, vasoconstriction of coronaries
Vagus nerve arises from … and travels… to get to heart
brainstem and travels through neck/thoracic inlet to get to heart
Parasympathetic Pre-ganglionic fibers arise from…
vagus nerve (travels within)
Parasympathetic post-ganglionic fibers are found on…
heart tissue
Sensory innervation for the heart is carried by what fibers? to where?
carried by sympathetic fibers T1-T4 (mainly on L) from heart to spinal cord and ultimately the brain
Sensory innervation of heart sends what kind of information to brain?
info about oxygen levels and metabolic byproducts (like lactic acid)– no conscious awareness, but brain constantly processing this info to regulate the heart
Referred Pain
vague painful stimulus (noxious stimuli – decrease in oxygen/accumulation metabolic byproducts) felt in structures with somatic sensory innervation in the T1-T4
Fools into thinking there’s somatic pain even though there is not
Referred Pain
Where does Referred pain occur?
T1-T4 region = part of chest, shoulder, and lower part of neck
What clinical correlate is associated with referred pain?
heart attack
