heart go lub dub

75 bpm

average contraction rate

70 mL per contraction at rest

cardiac output averages

location of heart

SPECIFIC: Pericardial cavity

Thoracic Cavity

BROAD: Ventral Cavity

apex

points left & sits in left lung’s cardiac notch

size

fist

9-12 ounces b/t male & female

looped, closed system

pumps in a system not open to outside

2 lobes

left lung

capillaries

where nutrients & O2 reach in tissues to deliver to cells

site of exchange

1 cell thick = efficient

systemic circuits

left side

endocardium

simple squamous endothelium cells (1 flat layer) lines chambers & valves

inner

bright blue layer

mesothelium

simple squamous layer

1 cell thick, flat layer

myocardium

striated = protein lines

branched cells

thicker left  side > overcome resistance

dark pink layer

epicardium

lays over heart, made of simple squamous cells

aka visceral layer

epi = on top of

light pink layer

visceral layer

touches heart

part of serous pericardium

aka epicardium

light pink layer

serous pericardium

2 layers

double fold membrane that secretes serous fluid (lubricant) b/t layers

visceral, parietal

light pink and light blue layer

parietal layer

outer serous pericardium

touches thoracic wall

light blue layer

fibrous pericardium

sac enclosing heart

tough

serous fluid

secreted by serous pericardium

lubricant

dark blue layer

coronaries

arise off aorta > left coronary super imporrtant + branches

right coronary artery

supplies right atrium & right ventricle

connected to aorta, to heart

coronary sinus & veins

drain heart to right atrium = O2 poor

atherosclerosis

fat plaque build up = narrow & harden arteries > lead to myocardial infarction (heart attack)

veins have valves that…

… keep blood moving 1 way

heart

muscle that needs O2 blood

sinus

cavity that connects to vein in this context

left coronary artery

divides into two branches

goes to left atrium and left ventricle

sends to circumflex artery

circumflex artery

supplies blood to elft atrium and back of left ventricle

arrow to LAD

left anterior descending artery (LAD)

supplies blood to front and bottom of left ventricle and septum

coronary veins

take oxygen-poor blood that has been used already by muscles of the heart and return it to right atrium

pulmonary arteries

fetal umbilical arteries (2)

only time when we have O2 poor blood in an artery

pulmonary veins

umbilical vein (1)

only time we have O2 rich blood in veins

3 adaptations: DV, OF, DA

bypass lungs bc they have fluid in them

fetal circulation adaptations

supposed to close up once born

1 umbilical vein

off placenta, sends rich O2 to fetal heart

2 umbilical arteries

branch off iliac arteries of fetus

return O2 poor/CO2 to placenta

placenta

exchanged piece, (membrane)

O2 and nutrients exchanged here

iliac

legs region

congenital defects

coarctated (narrow) aorta 

patent foramen ovale & patent ductus arteriosus: does not close > flow issues

tetralogy of fallout

4 congenital defects

1) pulmonary stenosis

2) right ventricular hypertrophy

3) overriding aorta

4) ventricular septal defect

pulmonary stenosis

narrowing > flow issues

Ductus venous

most O2 even blood skips liver (hepato, 80%) > vena cava > right artery

foramen (hole) ovale

bypasses right ventricle & pulmonary

How? pushes blood into left atrium

skipping lungs > bad after birth

ductus arteriosus

what happens if some blood gets into right ventricle?

opening b/t pulmonary artery and aorta

order 

placenta > umbilical vein > ductus venosus > oval foramen > ductus arteriosus > femoral arteries > iliac legs

atrioventircular (AV) valves

between atrium & ventricles

right AV (tricuspid) & left AV (bicuspid)

atria contract

high pressure pushes AV valves open & blood flows into ventricles high to low

ventricle contracts

high pressure pushes AV valves shut

s1 souund lub

blood pushes semilunar open

chordae tendinae

heartstrings

attached to valves > stop valve prolapse & regurgitation into atria

stabilizes valves >

prolapse

regurgitation

open backward

semilunars

exits w/ 3 flaps

pulmonary (stops regurg to RV) & aortic valve (stops regurg to LV)

ventricles relax

pressure drops in them = pulmonary & aortic valve close

sound S2 dup

atria contract

pulmonary V and aortic V closed

systemic side

left

pulmonary side

right

lungs regurgitate

left

body regurg

right