Blood Supply & Innervation of the Heart Flashcards
what do the coronary arteries supply?
myocardium and epicardium
*w/ oxygenated blood
what do the coronary arteries arise from?
the right and left aortic sinuses
right coronary artery gives rise to…
-sinoatrial nodal artery
-right marginal artery
-posterior interventricular artery
left coronary artery gives rise to…
-circumflex artery
-anterior interventricular artery
coronary arteries are…
functionally end arteries
end artery
only supply of oxygenated blood to a portion of tissue
*no anastomoses
why are the branches of the coronary arteries not true end arteries?
because numerous anastomoses take place b/w the L and R coronary arteries and b/w branches of the same artery
intercoronary anastomoses
b/w coronary arteries
intracoronary anastomoses
b/w branches of the same artery
R coronary artery supplies…
-R atrium
-R ventricle
-posterior 1/3 interventricular septum
-SA and AV nodes
L coronary artery supplies…
-L atrium
-L ventricle
-portion of R ventricle
-anterior 2/3 interventricular septum
-possible SA node (in 40% of population)
R coronary artery runs in _____
coronary sulcus
SA nodal artery supplies…
SA node
R marginal artery supplies…
R ventricle- does not reach apex
coronary artery dominance
defined by the artery that gives rise to the posterior interventricular artery
which dominance of the coronary artery is typical?
right
codominance of coronary arteries
both RCA and LCA give rise to branches that course in or near the posterior interventricular groove occurs very rarely
right dominant hearts have…
better collateral circulation than L dominant
coronary atherosclerosis
lipid deposits in the intima (lining) of coronary arteries
balloon angioplasty
uninflated balloon catheter inserted
balloon inflated, plaque compressed
widened artery
bumps left behind can still cause abnormal blood flow
CABG surgery
coronary artery bypass graft surgery
treatments for coronary artery disease
lifestyle changes, medications, angioplasty, and surgery
myocardial infarction
sudden occlusion of a major artery
region of the heart supplied by occluded vessels become infarcted (rendered bloodless) and becomes necrotic (tissue death)
most common cause of MI
coronary artery insufficiency from atherosclerosis
heart is drained mainly by…
veins that empty into the coronary sinus
small anterior cardiac veins drain…
directly into the R atrium
SA node
located in the wall of the R atrium
initiates cardiac muscle contraction and determines heart rate
AV node
located in the interatrial septum just superior to the opening of the coronary sinus
bundle divides into R and L bundle branches
conducting system
network of specialized tissue that stimulates contraction; modified myocytes
heart can contract w/o any innervation
where are preganglionic sympathetic neuron cell bodies located?
lateral horns of the spinal cord
where are postganglionic sympathetic neuron cell bodies located?
paravertebral ganglia
sympathetic innervation of the heart responsible for…
increasing heart rate, impulse conduction, force of heartbeat, and blood flow in coronary arteries
where are preganglionic parasympathetic fibers located in relation to the heart?
vagus nerve
where are postganglionic parasympathetic fibers located in relation to the heart?
in the cardiac tissue
parasympathetic innervation of the heart responsible for…
decreasing heart rate, force of contraction, and constricting coronary arteries
visceral pain pathways of the heart follow…
path of sympathetics backwards
visceral sensory pathways participate in
reflex actions that lower blood pressure and slow the heart rate
what nerve carries visceral sensory information for the heart?
vagus nerve
does the vagus nerve transmit any visceral pain originating in the heart?
NO
how many vessels does the umbilical cord contain?
3
2 umbilical arteries
1 umbilical vein
umbilical arteries
branches of the internal iliac arteries that carry deoxygenated blood away from the fetus
umbilical arteries become the…
medial umbilical ligaments of the anterior abdominal wall
umbilical vein
drains into the ductus venosus which drains into the IVC and BYPASSES THE LIVER
carries oxygenated blood from the placenta to the fetus
fetal blood circulation from inferior vena cava
IVC –> R atrium –> foramen ovale –> L atrium
ultimately circulated to the fetus’ head, neck, and upper extremities
fetal blood circulation from superior vena cava
SVC –> R atrium –> tricuspid valve –> R ventricle & pulmonary trunk –> aorta via ductus arteriosus
ultimately circulated to the fetus’ thorax, abdomen, pelvis, and lower extremities
