CV system Flashcards
CV system function
supply cells/tissues with oxygen/nutrients and to remove wastes (CO2, urea)
CV system structures
heart
blood vessels
*blood is a connective tissue, not part of this system
cardiology
study of the heart and the diseases associated with it
heart
location: within mediastinum
size: closed fist, 300g
base of heart
wide superior portion
apex of heart
inferior point
heart coverings
serous (visceral & parietal) pericardium
fibrous pericardium
visceral pericardium
innermost delicate epithelium
parietal pericardium
inner lining of fibrous pericardium
pericardial cavity
between visceral and parietal pericardium and is filled with serous fluid
fibrous pericardium
outermost tough, fibrous protective CT layer the prevents over-stretching of the heart
heart wall
epicardium
myocardium
endocardium
epicardium
visceral pericardium
myocardium
cardiac muscle tissue, bulk of heart
endocardium
smooth inner lining of heart chambers and valves
simple squamous epithelium called endothelium
heart chambers
atria
ventricles
atria
upper chambers
receive blood from veins (PASSIVE)
thin walled
flaps called auricles
interatrial septum
not complete during fetal development
fossa ovalis is remnant of fetal foramen ovale
ventricles
pump blood from the heart into arteries (ACTIVE)
thick walled
trabecular carneae
trabecular carneae
irregular inner surface (ridges and folds)
arteries
carry blood away from the heart
high in O2, low in CO2 EXCEPT pulmonary arteries
aorta
blood from left ventricle to body
pulmonary arteries
blood from right ventricle to lungs via pulmonary trunk
coronary arteries
cary blood to myocardium
richest blood supply
veins
carry blood toward the heart
low in 02, high in CO2 EXCEPT the pulmonary veins
superior vena cava
blood from the head and upper limbs
inferior vena cava
blood from the trunk and lower limbs
coronary sinus
blood from myocardium
drains all coronary veins
posterior side of heart
pulmonary veins
blood from lungs to left atrium
2 from each side
ligamentum arteriosum
remnant of fetal ductus arteriosus
80% of blood goes from R->L atrium
20% of blood goes to R ventricle->pulmonary trunk-> ductus arteriosus->aortic arch
heart valves
atrioventricular (AV) valves
semilunar (SL) valves
atrioventricular valves
tricuspid (R AV)
bicuspid (L AV)
tricuspid valve
lies between right atrium and right ventricle
bicuspid valve
aka mitral valve
lies between the left atrium and left ventricle
chordae tendineae
tendon-like fibrous cords that connect the cusps of AV valves to the papillary muscle
prevent cusps from swinging back into atria
hold valves shut during contraction
papillary muscle
muscular columns that are located on inner surface of the ventricles
semilunar valves
pulmonary SL (R SL) aortic SL (L SL)
pulmonary SL valve
lies within pulmonary trunk
aortic SL valve
lies within aorta
pulmonary blood flow
right atrium (deoxygenated) tricuspid valve right ventricle pulmonary SL valve pulmonary trunk pulmonary arteries capillaries pulmonary veins left atrium bicuspid valve left ventricle aortic semilunar valve ascending aorta
coronary blood flow
ascending aorta coronary arteries left & right coronary arteries capillaries in myocardium cardiac veins coronary sinus right atrium
left coronary artery
circumflex branch (backside) anterior interventricular (descending) branch (aka widow maker)
right coronary artery
right marginal branch posterior interventricular (descending) branch
anastomoses
connections between 2 ore more branches of arteries that supply the same region with blood
provide alternate routs for blood to reach a particular region
cardiac veins
great cardiac vein (alongside widow maker)
middle cardiac vein (alongside posterior IV branch)
common causes of heart problems
blood clots
fatty atherosclerotic plaques
smooth muscle spasms w/in coronary vessels
ischemia
reduction of blood flow in the presence of normal oxygen
hypoxemia
reduction of oxygen with normal blood flow
hypoxia
reduction of oxygen and blood flow
angina pectoris
severe pain accompanied by myocardial ischemia
crushing pain radiating down left arm
labored breathing, weakness, dizziness, perspiration
during exertion, fades with rest
relieved by vasodilators (nitroglycerin)
stable angina
pain on exertion relieved with rest
unstable angina
pain on exertion, no relief with rest
usually due to atherosclerosis
Prinzmetal angina
associated with vasospasm
idiopathic
myocardial infarction
pathological term
ischemic necrosis due to lack of oxygen
caused by thrombus or embolus in coronary artery
may result in sudden death if conduction system interrupted and ventricular fibrillation occurs
heart attack
clinical term
MI tests
ECG (EKG): wider QRS, arrhythmias
troponin levels elevated w/in 30 minutes, normal within 5-7 days
CKMB - creatinine kinase, cardiac; elevated 1-2h after, normal w/in 2-3 days
neutrophilic response within 4-7 days; could result in cardiac tampanade
MI treatments
clot dissolving agents (TPA, streptokinase)
heparin
angioplasty
reperfusion damage
when oxygen deprived tissue’s blood supply is reestablished
formation of free radicals
damage to enzymes, neurotransmitters, nucleic acids, phospholipids
reperfusion damage implications
heart disease parkinson's alzheimer's cataracts rheumatoid arthritis aging
antioxidants
defend body against free radicals
include enzyme catalase, vitamin A, C, E
cardiac conduction system
sinoatrial (SA) node
atrioventricular (AV) node
atrioventricular (AV) bundle (right and left branches)
purkinje fibers
SA node
located in right uppermost atrial wall
aka pacemaker; initiates cardiac impulses (60-100bpm)
travels through atrial fibers via gap junctions in intercalated discs to AV node
AV node
located in interatrial septum
delay signal that allows for ventricular filling
impulse travels to AV bundles
AV bundles
aka bundle of His
only electrical connection between atria and ventricles
located in superior interventricular septum
enters both right & left branches downward toward apex and purkinje fibers
perkinje fibers
aka conduction myofibers
large diameter
located within papillary muscles of ventricles
conduct impulse into mass of ventricular muscle tissue
cause ventricles to contract
electrocardiogram (ECG/EKG)
recording of the electrical changes that occur in the myocardium during the cardiac cycle
EKG uses
evaluate conduction pathways
heart enlargement
heart regions damaged
rules to remember (EKG)
depolarization precedes contraction
repolarization precedes relaxation