Chapter 18 Heart Flashcards
what is another name and the function for the entire right section of the heart?
pulmonary pump
pumps deoxygenated blood to lungs
what is another name and the function for the entire left section of the heart?
systemic pump
pumps oxygenated blood to entire body
where is the heart located within the body?
in the mediastinum cavity
2/3 left of the midline
where does the base of the heart point?
points towards right shoulder (up)
where does the apex of the heart point?
points towards left hip (down)
what is the apical impulse?
tapping of the apex of heart against 5th intercostal space
happens when left ventricle contracts (systole)
Describe the names of all layers of the pericardium
fibrous outermost layer
parietal layer of serous pericardium
pericardial cavity
visceral layer of serous pericardium (AKA: epicardium)
what is fibrous pericardium composed of?
tough, dense irregular connective tissue (similar to that of tendons)
what is the fibrous pericardium’s function?
protect
anchor
prevent overfilling
what is inside the pericardial cavity?
serous fluid
what is the function of the serous pericardium membranes and cavity?
to reduce friction
what is pericarditis?
peri - around
cardi - heart
itis - inflammation
inflammation of the pericardium
roughens serous membrane and heart rubs against pericardium
how can you tell someone has pericarditis?
creaking sound in stethoscope
deep pain over sternum
what can cause pericarditis?
infections
tissue death of the heart
what is cardiac tamponade?
“heart plug”
large amount of fluid accumulating in PERICARDIAL CAVITY causes heart inability to pump/expand
What can cause cardiac tamponade?
prolonged pericarditis
How can we treat cardiac tamponade?
cardiocentesis:
cardio - heart
centesis - puncture w/hollow needle
drain fluid with catheter (not a permanent solution - need to find the root cause)
what are incompetent valves?
leaky/ improperly functioning valves within the heart
why are incompetent valves dangerous?
can cause backflow
cause inadequate blood flow to tissues
how can you diagnose incompetent valves?
abnormal heart sounds
what are two ways we can treat incompetent valves?
mechanical replacements (made from metal)
organic replacements (made from cadavers/ pig valves/ reconstructed w/ cow pericardium)
what are pros/cons of using mechanical replacement valves in the heart?
last a long time
but the patient would need to be on blood thinners to reduce the chance for clotting against the foreign object in the heart
what ways are biosynthetic valves made safe for humans?
tissue is treated and antigens are removed so that it won’t be rejected
what is a mitral valve prolapse?
left A.V. valve is prolapsed and bulges upwards toward the left atrium, due to chordae tendinea not holding mitral valve sufficiently in place
how common is having a mitral valve prolapse?
fairly common - effecting 1% of population
but 7% chance of finding in autopsy
what can mitral valve prolapse lead to?
incompetent valve
irregular heartbeat
pain
shortness of breath
what is an angina pectoris?
brief spasm causing brief loss of blood to myocardium
what can cause an angina pectoris?
stress
physical activity
Is an angina pectoris life-threatening?
not necessarily
muscle cells weaken but do not die
what is a myocardial infarction? What causes it? 
a heart attack
caused by prolonged coronary artery blockage from blood clots or plaque
what happens to muscle cells in a myocardial infarction?
muscle cells actually die and can leave the heart unable to beat where death occurred.
if cells are able to replace they are replaced only with connective tissue that leaves scars, which do not function the same as heart tissue
how can we tell if someone has had a heart attack?
viewing bloodwork for traces of CPK (creatine protein kinase) or troponin
when heart muscle cells die, the cell breaks down and proteins leak into the bloodstream. Certain proteins can be found only in live muscle cells and should not be found in the bloodwork unless a heart attack/death of heart muscle cell has occured
Describe the layers of the heart (without the pericardium)
epicardium
myocardium
endocardium
describe what the epicardium is
most superficial layer of the heart
same thing as visceral layer of the serous pericardium
full of fat as we age
describe what the myocardium is
middle muscular layer of the heart
thickest on the left ventricle side of the heart
why is the myocardium thickest on the left ventricle side of the heart?
heart needs to pump significant pressure to get blood to every part of the body
describe the endocardium
lines chambers and valves
is continuous with lining of blood vessels that lead out of the heart
what is the endocardium made of?
white, smooth endothelium that contains squamous epithelial cells on layer of connective tissue
what is the function of the endocardium?
reduces friction between blood and heart
true/ false? most of the heart is in the exact center of the thoracic cavity. If false, where is it located?
false; 2/3 of heart fall left of the body midline
predict what would happen to the myocardium if the right side of the heart had to push against as much pressure as the left side does
the right ventricle wall of myocardium would be thicker
what is the generic name for the valves that connect either atria to its ventricle?
A.V. valve - atrioventricular valves
what is the generic name for the valves that connect either ventricle to its designated artery?
S.L. valve - semilunar valve
when do the A.V. valves open?
when there is more pressure in the atria than the ventricles
when do the AV valves close?
when the ventricles contract (to prevent backflow)
what are the names of specific AV valves? What do they direct blood flow of?
tricuspid valve (AKA: right AV valve) - connects RIGHT atrium and right ventricle
bicuspid valve (AKA: left AV valve/ Mitral valve) - connects LEFT atrium and ventricle
what is the function of the chordae tendineae?
when ventricles contract, tugging of the cord occurs to keep the AV valves closed during contraction
what is the chordae tendineae made of/ attached to?
they are collagen cords attached to papillary muscles located on the side walls of the ventricles. Thereby connecting the AV valves to the ventricular wall
when do the SL valves open?
when pressure in ventricles is greater than pressure in arteries
when do the SL valves close?
when ventricles relax, blood flows backward and fills the cusps closed
what is another name for chordae tendineae?
heart strings
what are the names of the two SL valves and what do they connect?
Aortic SL valve - connects left ventricle to the aorta
pulmonary SL valve - connects right ventricle to pulmonary trunk
name three similarities between AV and SL valves
both have cusps
both prevent backflow
both are flaps of connective tissue
name three differences between AV and SL valves
- the blood flows in different directions (ie: AV valves control blood leaving downward/ SL valves control blood leaving upward)
- only AV valves have chordae tendineae
- AV valves open when ventricles are relaxed/ SL valves open when ventricles contract
How many microns is the diameter of a RBC?
8-10 microns
Sketch the heart’s layers (and their brief function), atrium, ventricles, valves, arteries, veins, and direction of blood flow
what is the function of coronary arteries? what are they connected to?
supply the heart with blood
leave the aorta and wrap towards the left and right of the heart
How do the coronary arteries work?
they deliver blood to the heart when the heart is relaxed through the left and right coronary artery (they are squeezed shut when the myocardium contracts)
if the coronary arteries are blocked, what will happen?
oxygen will not be delivered to the heart causing a heart attack
what is the function of cardiac veins?
collect blood and dump it back to the heart
what are the parts of the cardiac veins and where are they located?
great, middle, small cardiac veins - drain blood into coronary sinus
coronary sinus - drains directly into the right atrium
list 6 cardiac defect and a brief description
which is the least likely to be life-threatening?
angina pectoris or mitral valve prolapse