2/12 quiz Flashcards
Atherosclerosis
plaque formation causeing the narrowing of blood vessels (staosis)
thrombus
clot that is free flowing and can block blood vessel
coronary thrombosis = heart attack
cerebral thrombosis = stroke -> paralyisis
Arteriosclerosis
Calcification (calcium deposit) so the/any blood vessel becomes hard, no expansion.] when blood comes so blood pressure rises, narrow now so less blood flows
(normally blood is supposed to be soft expand and contract with each heartbeat to help move blood throughout the body.)
transient ischemic attack (TIA) or cerebrovascular accidentin
when blood circulation stops for a few seconds in heart/brain
aneurysm
when clot that block blood vessel, it’ll balloon/swells
Angioplasty & stent
angioplasty is a procedure used to open narrowed blood vessels using stent
chambers of the heart
Right Atrium (thin):
Structure: Receives deoxygenated blood from the body through the superior and inferior vena cavae.
Features:
Interatrial Septum: The wall separating the right and left atria.
Fossa Ovalis: A depression in the interatrial septum, marking the site of the foramen ovale in fetal circulation.
Foramen Ovale: An opening in the fetal heart that allows blood to bypass the lungs; it typically closes after birth.
Left Atrium (thick walled):
Structure: Receives oxygenated blood from the lungs via the right and left pulmonary veins.
Features:
Interatrial Septum: The wall separating the left and right atria.
Fossa Ovalis: Located in the interatrial septum, indicating the site of the foramen ovale.
four heart valves
- Atrioventricular (AV) Valves:
Left AV Valve (Bicuspid or Mitral Valve): Located between the left atrium and left ventricle, it has two flaps and ensures blood flows from the left atrium to the left ventricle without returning.
Right AV Valve (Tricuspid Valve): Situated between the right atrium and right ventricle, it has three flaps and prevents blood from flowing back into the right atrium.
- Semilunar Valves:
Pulmonary Valve: Located at the base of the pulmonary artery, it has three flaps and controls blood flow from the right ventricle to the lungs.
Aortic Valve: Found at the base of the aorta, it also has three flaps and regulates blood flow from the left ventricle to the body.
Additional Structures:
these prevent blood from going back into the atrium
Chordae Tendineae: These are tendon-like cords that connect the AV valves to the papillary muscles in the ventricles, preventing valve inversion during contraction.
Papillary Muscles: Located in the ventricles, they contract to tighten the chordae tendineae, ensuring the AV valves close properly.
incompetant valves
When heart valves don’t close properly, they allow blood to flow backward, a condition known as regurgitation. This backward flow can cause a heart murmur
valvular stenosis
when a heart valve becomes thickened and narrowed, often due to calcification, reducing blood flow through the heart. This narrowing can produce a characteristic swishing or hissing sound, known as a heart murmur.
artifical/ mechnical value or pig valve (not rejected by body) can be used
A-V valves close
first sound “lub”, low pitch, longer duration
semilunar valves close
higher pitch, shorter duration
Aortic insufficienc
when the aortic valve doesn’t close properly, allowing blood to flow backward into the left ventricle (left valve more likely to fail)
heart valves electrical current
look at the flow. sa nofe, av node, bundle of his, rt undle branches or lt branches (purkingie fibers )
fibrous ring
The fibrous rings of the heart, also known as the cardiac skeleton, are dense connective tissue structures that electrically isolate the atria from the ventricles. This isolation ensures that electrical impulses are confined to the atria and ventricles, preventing direct transmission between these chambers.
cardiac muscles
striated, branched (not under your control), electrically coupled via gap junctions & desmosomes, aeroric (ned lots of oxy, ,ito. non fatigable, spiral arrangement- help squeeze out the blood. Cardiac muscle is the heart’s specialized tissue responsible for its rhythmic contractions. It is striated, meaning it has a striped appearance due to the arrangement of actin and myosin filaments. The muscle fibers are branched and interconnected, forming a network that facilitates synchronized heartbeats. Unlike skeletal muscle, cardiac muscle operates involuntarily, meaning its contractions are not under conscious control. It relies on aerobic metabolism, requiring a constant supply of oxygen to function effectively. Due to its high mitochondrial content, cardiac muscle is non-fatiguing, enabling continuous contraction throughout life. The muscle fibers are arranged in a spiral pattern, which helps to efficiently squeeze blood out of the heart chambers during contraction.
endocardium
innermost layer of the heart wall, lining the heart chambers and covering the heart valves. It is composed of a simple squamous epithelium known as endothelium, which is continuous with the endothelial lining of the blood vessels.
two types of cell muscles in heart
peacemaker cells 1%
excitable cells -> generate action potential, autorhythmic (no external nervous stimulus needed, not contractile
cardiomyocytes 99%
excitable cells -> action potentionm, autorhythmi( no stimulus needed, contractile -> generate force
Myogenic Heart (humans) & Neurogenic Heart (insects n stuff)
human heart is myogenic, meaning it generates its own rhythmic contractions without external nervous input.
ympatheic nerves uses epinephrine to speed up heart, makes heart beat faster.
neurogenic heart relies on nerve impulses to initiate and regulate its contractions.s
sinoatrial (SA) node
located in the right atrium, is the heart’s primary pacemaker. It generates electrical impulses that set the heart’s rhythm, known as the sinus rhythm. 70 beats/min
atrioventricular (AV) node
serves as a reserve (secondary) pacemaker, AV node can take over if the SA node fails
40-60/min
parkinje fibers
if sa and av fail, this will take over at 20-40 beats/min
peacemaker cell
1:07 in recording
sodium entry there will depolerization(thisis the action potential which this is the simulus for muslce to contract) then going back to resting opotetional (repolarization k+ exit)
cardiomyocytees
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