Chapter 19 Flashcards
principal función of cardiovascular system
providing adequate perfusion
what’s perfusion?
delivery of blood per time per gram of tissue mL/min/g
the right ventricle send blood to the lungs via
pulmonary trunk
what are the only arteries that carry deoxygenates blood?
pulmonary arteries
largest artery
aorta
left ventricle send blood to the entire body via
the aorta
large veins
superior and inferior vena cava
vena cava from______ to _____
body, right atrium
only veins that carry oxygenated blood
pulmonary veins
pulmonary semilunar valve is between
right atrium and pulmonary trunk
aortic semilunar valve is between
left atrium and aorta
pattern of blood circulation
right atria ~ right ventricle ~ pulmonary trunk ~ lungs ~ eft atria ~ left ventricle ~ aorta ~ systemic circulation ~ SVC ~ right atria
the heart is posterior to the
sternum
the heart is in the _____ cavity
mediastinum
the apex of the heart points down into the _____
left
mention the 3 layers of the pericardium
fibrous pericardium
parietal layer of the serous pericardium
visceral layer of the serous pericardium
two serous layers separate by
pericardial cavity
type of tissue of fibrous parietal layer
dense irregular connective tissue
type of tissue of the two serous pericardium layers
simple squamous epithelium and areolar connective tissue
what does the pericardial cavity contain?
serous fluid
why is the left side of the heart thicker?
it works harder because sends blood to all the body
what happens with the capillaries in pericarditis?
increases capillary permeability which causes fluid accumulation in pericardial cavity which restricts chamber’s movement
pericarditis results in_____
cardiac tamponade
what’s visible in the anterior view?
right atrium
right ventricle
right auricle (most)
pulmonary trunk
ascending aorta
aortic arch
descending aorta
portions of: left auricle and ventricle
what’s visible in the posterior view?
left atrium
left ventricle
pulmonary veins (left atrium)
IVC, SVN
pulmonary arteries
posterior interventricular sulcus
part of coronary sulcus
coronary sulcus is separates _____ from_____
atria, ventricles
AV valves close when ______ _____
ventricles contract
AV valves prevent back flow to
atria
semilunar valves prevent back flow to
ventricles
semilunar valves open when
Av valves close and ventricles contract
symptoms of cardiomegaly
shortness of breath, dizziness, swelling, arrhythmia
heart murmur
abnormal heart sound
4 normal heart sounds
S1 - AV valves close
S2 - semilunar valves close
S3 S4 minor sounds
type of tissue the fibrous skeleton is
dense irregular connective tissue
function of fibrous skeleton
supports atria and ventricles
valves anchor to it
framework for the heart
prevents ventricles to contract at the same time as atria
cardiac cells have ____ nuclei
2
what structure is only part of cardiac cells?
intercalated discs
what are the 2 types of junctions in the intercalated discs?
desmosomes, gap junctions
describe desmosomes
proteins filaments, mechanically joint cells
describe gap junctions
electrically or functional joint cells
ischemic
low oxygen
cardiac muscle use different types of_____ (glucose, lactic acid, fatty acids, amino acid, ketone bodies)
fuel molecules
cardiac muscle relies on _____ metabolism
aerobic
right coronary artery branches:
marginal artery
posterior interventricular artery
left coronary artery branches:
circumflex artery
anterior interventricular artery
coronary arteries are different because
they’re functional end arteries
arterial anastomoses are
connections between vessels to provide more than one route
why arterial anatomies doesn’t work on the heart?
coronary anastomoses are too small
what happens with coronary flow when the heart contracts?
vessels compressed interrupting flow
mention the coronary veins and their location
great cardiac vein - anterior interventricular
middle cardiac vein - posterior interventricular
small cardiac vein - next to right marginal artery
coronary sinus -
function of coronary sinus
receive blood from cardiac veins and drains into right atrium
3 things that go into the right atria
SVC
IVC
coronary sinus
pain in the chest
angina pectoris
coronary spasm
narrowing of the vessels
myocardial infarction
heart attack
what does the SA node does?
initiates heartbeat
another name for sinoatrial node
pacemaker
location of SA node
high in right atrium
location of AV node
floor of the right atrium
AV bundle extends from _____ through ______
AV node, interventricular septum
AV bundle divides into
right and left bundles
purkinje fibers go through
ventricles
describe conduction system
initiates and conducts electrical events
location of the cardiac center
medulla oblongata
cardiac center contains
cardioacceleratory, cardioinhibitory
cardiac center receives signal from
baroreceptors and chemoreceptors
parasympathetic innervation starts at ______ via _____
cardioinhibitory center, vagus nerve (X)
sympathetic innervation starts at _____ via ______
cardioacceleratory center, neurons from T1-T5
____ vagus enervates SA node
right
left vagus innervates ____ node
atrioventricular AV
heart contraction involves two events
conduction system
cardiac muscle cells spread action potentials and contract
what’s the function of a nodal cell?
starts the action potential
what’s the resting membrane potential of nodal cell?
60mV
mention the 3 electrical events at SA node
threshold
depolarization
repolarization
what happens in the threshold?
slow voltage-gated Na channels open
Na flows in
membrane potential from 60mV to 40mV
process of depolarization (nodal cell)
fast voltage-gated Ca channels open
Ca flows in
membrane potential from 40mV to above 0mV
process of repolarization (nodal cell)
Ca channels close
voltage-gated K channels open
K flows out
RMP back
voltage-gated Na channels open
process begins again
numbers of heartbeats at rest
75 per min
function of vagal tone
keeps resting heart rate slower
action potential is delayed at ____ node
AV
this delayed allows
ventricles to fill before they contract
where does heart stimulation begin?
apex of the heart
what’s the resting membrane potential of cardiac muscle cells?
90mV
electrical events of cardiac muscle action potential
depolarization
plateau
repolarization
process of depolarization (cardiac muscle)
fast voltage-gated Na channels open
Na enters the cell
membrane potential from 90mV to 30mV
process of plateau phase
voltage-gated K channels open
slow voltage-gated Ca channels open
K leaves
Ca enters
membrane potential remain depolarized
process of repolarization (cardiac muscle)
voltage-gated Ca close
K channels remain open
RMP back
in the mechanical events, who initiates?
Ca binding with troponin
P wave
atrial depolarization
QRS complex
ventricular depolarization
atrial repolarization
T wave
ventricular repolarization
P-Q segment
atrial plateau
atrial contraction
S-T segment
ventricular plateau
ventricular contraction
P-R interval
from beginning of P wave to before Q deflection
Q-T interval
from beginning of QRS to end of T wave
cause of cardiac arrhythmia
heart blocks
impaired conduction
first degree block
long P-R segment
between ventricles and atria
second degree block
some atrial action potentials are not getting to the ventricles
third degree block
all actions potentials are no getting to the ventricles
cardiac cycle: all the events from ____ to
one beat, the next
systole
contraction
diastole
relaxation
ventricular contraction: what happen to AV valves and semilunar valves?
AV valves close
semilunar valves open
ventricular relaxation: what happen to AV valves and semilunar valves?
AV valves open
semilunar valves close
stroke volume (SV)
amount of blood ejected by ventricle
end systolic volum (ESV)
amount of blood remaining in the ventricle after its contraction
edema
swelling. collection of interstitial fluid
cardiac output
measures how effective the cardiovascular system is
formula for cardiac output
heart rate times stroke volume
positive chronotropic agents
increase heart rate via sympathetic division
mention positivé chronotropic agents
caffeine
thyroid hormone
nicotine
cocaine
negative chronotropic agents
decrease heart rate via parasympathetic activity
venous return
volume of blood returned to the heart
The primitive ventricle forms most of the _____ ventricle.
left
During weeks ______, the single heart tube becomes partitioned into four chambers (two atria and two ventricles), and the main vessels entering and leaving the heart form.
5-8
Stroke volume (SV) in a healthy adult is approximately ______
70 ml
stroke volum formula
EDV - ESV
What are the cell-to-cell contacts of the cardiac muscle fibers called?
intercalated discs
Vagal tone refers to the
decreasing of the heart rate below its inherent rhythm by parasympathetic stimulation
To initiate a cardiac muscle cell contraction, calcium
binds to troponin
Blood moves into and then out of a heart chamber because
it moves along its pressure gradient, and that gradient depends on contraction and relaxation during the cardiac cycle
three main factors influencing stroke volume
venous return
afterload
inotropic agents
The tetralogy of Fallot is
a developmental disorder that is a cardiac septal defect.
