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Key Terms

arteries
blood vessels that carry oxygenated blood from the heart to the body
arterioles
arteries shrink to this smallest form and link with capillaries
atria
the top two heart chambers
atrioventricular (AV) node
a second node in the heart that creates a delay in the electrical impulse from the SA node to the bundle of His to allow time for ventricular filling
bundle of His
a bundle of conducting fibers that branch to each ventricle of the heart
capillaries
the point at which arteries and veins exchange blood supply
cardiovascular system
a system within the body that includes the heart, blood vessels, blood, lymph, lymphatic vessels, and glands that moves blood and lymph through the body
circulatory systems
interconnected blood vessels that flow through the body
electrocardiogram (ECG/EKG)
a recording of a heart’s electrical activity in which electrodes are placed on the chest to capture signals
hypoalbuminemia
a condition where the body does not produce enough albumin, a protein that keeps fluids in blood vessels
normal sinus rhythm (NSR)
the heart’s cardiac rhythm that originates from the sinus node
perfusion
the movement of blood, oxygen, and nutrients to tissues in the body
pulseless electrical activity (PEA)
electrical conduction throughout the heart without physical movement of the heart muscle
Purkinje fibers
terminal-conducting fibers in the ventricles
sinoatrial (SA) node
the pacemaker of the heart
telemetry
the measurement of a heart’s ECG through a portable device that automatically transmits to a monitor
veins
blood vessels that carry deoxygenated blood from the body to the heart
ventricles
the bottom chambers of the heart
venules
the smallest veins that link with capillaries
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