cardiology

explain the pathway of blood through the heart

deoxygenated blood is in the veins

the blood enters the right atrium through the vena cava

then through the tricuspid valve into the right ventricle

through the pulmonic valve out the heart to the lungs via pulmonary artery

this is where the oxygen sticks to the hemoglobin

then comes back to the left atrium via pulmonary vein

goes out the mitral valve into the left ventricle which contracts to push the blood out the aortic valve out to the rest of the body

artery

away from the heart

vein

towards the heart

preload

fill the heart (inferior vena cava → superior vena cava → right atrium)a

after load

pumping the blood out of the heart (LV → aorta)

valve

one way

how the blood leaves top to bottom or out the heart

coronary artery

supplies oxygen to the surface of the heart

systole

heart contracting

diastole

the heart relaxing

automaticity

the cardiac muscle cells contract without stimulus from the nerves

the heart has its own electrical system that dictates the rhythm

it is supposed to start at the SA node (anything else is irregular and dangerous to the heart because it adds extra beats or stalls, not allowing the enough volume to be pumped or pushed out)

contractility

the strength of the contractions

stretch ventricles to pump harder

cardiac output

the amount of blood the heart pumps (L/min)

CO = stroke volume x heart rate

stroke volume

the amount of blood ejected per contraction (mL*s)

heart rate

beats per minute

ejection fraction

normal 50-75%

how well pump blood out of the left ventrical

EF = stroke volume / end diastolic volume * 100

end diastolic volume

120 mL

amount of blood in ventricells before the heart contracts

electrical system

starts in the SA node, then both atria contract

then AV node (slows for the blood to pass the ventricles

controlled by the autonomic nervous system

autonomic nervous system

controls things that don’t need thought

sympathetic and parasympathetics

sympathetic

flight or flight

hr increase, bp increase, pupils dilate, glucose to your muscles

parasympathetic

to calm you down

slows the HR, lowers BP

myocardium

heart muscle

• needs o2 and nutrients to keep going

• more stress= more need for oxygen so your HR increases

arteries

the aorta spits into arteries

• femoral, carotid, ulnar, illid, radial, brachial

• these are where you can feel a pulse

arterioles

arteries branch into smaller

capillaries

are the smallest

they transport oxygen to the tissues and remove co2

venules

smallest veins that go back to the heart

red blood cells

carry oxygen

white blood cells

fight infections

plattlets

allow for clotting

plasma

liquid so the blood floats

carries nutrients, water, and proteins

perfusion

constant flow of o2

need a good heart (not too fast or slow)

good amount of blood

and good blood vessels (properly contricted)

ischemia

decreased blood flow to the heart

causes chest pain

atherosclerosis

calcium and fatty cholesterol builds and forms plaque on blood vessel walls

• interferes with the ability to constrict of dilate

• causes occlusions (blockages of the coronary artery)

  • they can grow

thromboembolism

blood clot gets stuck and blocks blood flow → hypoxia

acute myocardial infarction is it occurs in the coronary artery

infarction

death of tissue

cardia arrest

the heart completely stops pumping

risk: high cholesterol, smoking, obesity, high blood pressure, diabetes, lack of exercise, stress, genetics

acte coronary syndrome / ACS

a group of symptoms causes by MI

• chest pain

  • you would give aspirin and nitro

angina pectoris

heart tissue not getting enough oxygen → chest pain

• when the demand of oxygen is higher than output

• crushing, squeezing pain

• radiates to the chest

• 3-8 mins

• shortness of breathe, nausea, sweating

stable: goes away with rest

unstable: not provoked by exercise, nothing helps it

acute myocardial infarction

actual cell death (once it dies, you cannot bring it back) → scar tissue and can block blood flow

• more likely in the LV

• sudden weakness, nause, sweating, chest pain ,lower jaw, back, arms, abdomen, and neck discomfort

• syncope, irregular rhythm

• may or may not have been causes by something

• may or may not help iwth nitro

  • lasts 30- hours

dysthymias

the heart is not pumping at an adequate rhythm

tachycardia

beating too fast

bradycardia

beating too slow

ventricular tachycardia

radip, electrical starts in a ventricle instead of the artery → less cardiac output

one of the shockable rhythms

ventricular fibrillation

disorganized, ineffective quivering, no blood pump

one of the other shockable rhythms

cariogenic shock

the heart fails as a pump and now the body is trying to save the vital organs

s/s: anxiety, impending doom, restlessness, pale, cool, clammy skin, heart rate increase then weakens, rapid, shallow breaths, vomit, temperature drops, blood pressure later drops significantly

treat: semi fowler or supine (whatever is most comfortable, give oxygen, ventilate if needed, blanket

congestive heart failure

heart is not working properly

s/s: easier breathing while sitting up, chest pain, distended neck veins, high HR, BP, respirations, and pulse, pale, sweaty, cyanotic, crackles and rales

treat: call ALS

take vitals, CPAP and oxygen, sitting up, give nitro

right CHF

can’t pump the blood to the lungs

it backs up in the veins and fluid is in the legs (pitting edema)

left CHF

coronary artery disease

lost ability to move oxygen to the rest of the body (LV not pumping)

backs up into the lungs, fluid in the lungs, shortness of breath

hypertensive emergency

>180 mm systolic

s/s: sudden severe headache, pulsing, ringing, nausea, dizziness, vomiting, warm, moist, altered mental status

leads to aortic aneurysms and dissecting aneurysms

aortic aneurysms

weak aortic walls → rupture

causes internal bleeding

dissecting aneurysm

inner layers separate → ruptures

causes internal bleeding

• both arms have different BP

automatic implantable cardiac defibrillators/ AICD)

if someone is at high risk for a heart attack, this can assess their rhythm and shock them if needed

external defibrillator vest

monitors rhythm and can shock if needed

left ventricular assist device / LVAD

the person has no pulse, the device is pumping for them

cardiac arrest

no pulse

automated external defibrillation

measures the electrical rhythm and gives shocks when can

• only 2

• v-fib and v-tach