Med Occs Cardiac System

parts of cardiovascular system

heart, coronary arteries, arteries, veins, and capillaries

function of cardiovascular system

circulation of blood throughout the body that carries oxygen and nutrients to the cells and removes waste products from the cells

tricuspid valve

valve between the right atrium and right ventricle

bicuspid/mitral valve

valve between the left atrium and left ventricle

layers of heart wall

epicardium, myocardium, endocardium

layers of pericardial sac

fibrous pericardium, parietal pericardium, pericardial cavity, visceral pericardium/epicardium

pathway of blood flow

lungs → pulmonary veins → left atrium → bicuspid/mitral valve → left ventricle → aortic semilunar → aortic arch + branches → body

cardiac cycle

events in one heartbeat

describe the events in the cardiac cycle

SA node starts the heart → excitation spreads throughout atrial myocardium → AV node fires → signal spreads down to AV bundle branches → purkinje fibers distribute excitation through ventricular myocardium

systole

phase of contraction

diastole

phase of relaxation

cardiac output

amount of blood ejected in one minute

cardiac output formula

cardiac output = heart rate X stroke volume

pre-load

tension before heart begins to contract

contractility

how hard contracts for a given preload

afterload

sum of all forces a ventricle must overcome before ejecting blood

proprioceptors

special stretch receptors that prevent overfilling of chambers

baroreceptors

pressure sensors in carotid sinus and aortic arch - blood pressure

chemoreceptors

chemical receptors that sense changes in a variety of molecules in blood

systemic circuit

body (head, arms, trunk, and legs)

pulmonary circuit

lungs

arteries

carry blood away from the heart

arterioles

smaller arteries that branch to become capillaries (smallest type of arteries)

capillaries

carry blood from arterioles to venules; microscopic vessels designed to exchange nutrients and waste with the tissue

venules

smallest veins formed from united capillaries

veins

carry blood to the heart; contains valves to prevent backflow

vessels pathway for blood

arteries → arterioles → capillaries → venules → veins

conducting artery

largest type of artery

distributing artery

medium-sized artery

carotid sinuses

sense blood pressure

carotid bodies

monitor blood oxygen levels and pH

aortic bodies

monitor blood oxygen levels and pH

edema

excess fluid in tissues (swelling)

left coronary artery

branches out into circumflex and LAD

right coronary artery

branches out into marginal and PDA

hemodynamics

physical principles of blood flow

blood pressure

the force blood exerts against a vessel wall

resistance

friction or opposition that blood encounters in vessels

flow

amount of blood moving through and organ, tissue, or vessel

hypertension

high blood pressure

hypotension

low blood pressure

vasoconstriction

narrowing of vessel

vasodilation

widening of vessel

myocardial

pertaining to heart muscle

endocardium

within the heart

angiogram

X-ray record of a vessel taken during angiography

atherosclerosis

caused by formation of yellowish plaques of cholesterol on the inner walls of arteries

pericardial

pertaining to around the heart

vena

vein

pulmonary

pertaining to the lungs

atrial

pertaining to the atrium

ventricular

pertaining to the ventricles

bicuspid

having two ends (referring to the mitral valves)

interatrial

pertaining to between the atria

semilunar

shaped like a half moon (referring to the valves of the root)

diastolic

pertaining to the phase of relaxation of the heart (when the chambers fill with blood)

systole

phase of heart contraction

cardiac

pertaining to the heart

bradycardia

abnormally slow heart rate

tachycardia

abnormally fast heart rate

phlebotomy

incision into the vein (to draw blood)

ischemia

reduced blood flow to the tissues

varicose

swollen, twisted veins

angiospasm

sudden contraction of a blood vessel

vasodilation

widening of blood vessels

angioplasty

surgical repair of the blood vessel

aortic

pertaining to the aorta

arrhythmia

irregular heartbeat

pectoral

pertaining to the chest

cardiomyopathy

disease of the heart muscle

aneurysmectomy

surgical removal of an aneurysm

valvoplasty

surgical repair of a heart valve