heart all

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 from mom to baby

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

fetal 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 1

high pressure pushes AV valves open & blood flows into ventricles high to low [1]

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 dub

atria contract

pulmonary V and aortic V closed

systemic side

left

pulmonary side

right

lungs regurgitate

left

body regurg

right

systole

contract phase & pressure increases

diastole

relax phase and filling

if ventricles are contracting & pumping blood thru valves…

…atria are relaxed and filling

depolarize

electrical activity/stimulate

contraction/systole

repolarize

reversal of electrical activity, relax

P waves

record electrical activity through upper heart chambers

atrial depolarization (electrical)

contracting atria (systole)

should not be more than 1-2 large box tall & no more than 2.5 boxes wide

PR interval

time from beginning of P wave to beginning of QRS Complex

heart health, diagnose diseases

QRS Complex

records the electrical activity through the lower heart chambers

vascular depolarization (e), contracting ventricles = systole

R (highest), S (lowest)

T waves

records the electrical activity through upper heart chambers

atrial repolarization (relax), relaxing atria = diastole

Cardiac output

volume pumped by ventricles per minute.

Maintain blood flow throughout body, measure of blood volume ejected from heart over given time

Heart rate x Stroke volume

Avg: 5.2 L -5.25 L (blood in body)

stroke volume

mL pumped per ventricle contraction (avg=70mL)

amount for blood ejected from ventricles during one heartbeat

heart rate

BPM (avg 75)

cardiac output affected by

hormones, stress, age, stimulants (caffeine/meth), depressants, chemoreception (CO2 detection)

chemoreception

CO2 detection

high CO2=acid

cardiac output increases > get blood to lungs

adrenaline

sympathetic

stress system

what beta adrenegic receptors respond to

beta adrenegic receptors

respond to adrenaline

get blocked by beta blockers = competitive inhibition

when no adrenaline, cardiac output decreases > blood pressure decreases

parasympathetic system

“rest & digest”

neurons release acetylcholine neurotransmitter = slows HR and contraction force

Acetylcholine (ACH)

part of parasympathetic system > lowers cardiac output & BP

max rate

take 220 BMP - age

blood pressure

force exerted on artery wall

systolic blood pressure

top number

left ventricle contracts & pressure is passed to aorta wall muscle which distends/bulges/dilates

(90-120 mmHG)

diastole blood pressure

bottom number

left ventricle relaxes & aorta recoils on blood > pushes flow

(60-80 mmHg)

sphygmomanometer

cuff closes artery → listen

as pressure released, BP overcomes the cuff = artery opens

reads sound/korotkoff

Korotkoff

sound starts = systole reading (120)

once sound stops = diastolic pressure reading (80)

BP influenced by

epinephrine, T3

Compliance

how easy a vessel stretches > elastic

atherosclerosis reduces it

atherosclerosis

hardening artery

coronary artery disease

leads to MI (Heart attack)

volume

if decreased, pressure/flow rate decreased

ischemia

lack of flow to tissue & no perfusion

augustus gloop

decreased blood = decreased oxygen

perfuse

through

volume of blood that flows through tissue (organs) per minute

myocardial infarction

ischemia/ block of blood & oxygen to myocardium > necrosis (death)

heart attack

ischemia symptoms

left arm pain

angina (chest pain)

dyspnea (diffculty breathing)

vomiting (emesis)

diaphoresis (excess sweating)

cyanosis (turn blue bcos no Oxygen)

cardiopulmonary resuscitation

manually compress blood in heart to push some into pulmonary & systemic circuits

standard call for compression of chest 5 cm deep & at a rate of 100 compressions/minute

ekg order

P waves > PR interval > QRS complex > T waves

heart’s conduction system

1) Sinoatrial node

2) atrioventricular node

3) bundle of his in interventricular septum (wall)

3) purkinje fibers in ventricles

Sionatrial Node (SA) 

where pacemaker be

special cardiomyocytes in right atrium

depolarizes to start a sinus rhythm = spreads thru atria cells at once via gap junctions = atrial contract (systole)

gap junctions

special cell membranes electrical currents go through

intercalated disks

purkinje fibers

in ventricles

ventricle systole/contract

fibers of a tree, distribute to muscle

cardioversion

procedure where an arrhythmia is converted to a normal sinus rhythm (heartbeat)

pacemakers, AEDs

Rheumatic heart disease

strep (bacteria) infection

migrates to mitral valve

inflames & becomes stenotic (narrow)

valve prolapse

valve opens backwards

results in regurgitation

blood flows back > murmur (abnormal sound)

heart failure

pumping weakens & myocardium enlarges & stretches as tries to compensate for poor cardiac output

cardiac output continues to get worse = less blood flow/min from ventricles

congestive heart failure

way large, left side is thin

right-side heart failure

heart can’t pump enough blood to lungs to pick up O2

fluid build up in feet, legs, abdomen

bad blood flow → regurgitation

left-side heart failure

heart can’t pump enough oxygen-rich blood to rest of body

fluid back up to lungs

shortness of breath

bad blood flow → regurgitation