heart wall consists of three layers
- epicardium: OUTERmost layer
- Myocardium: MIDDLE layer of muslce fibers that contract to pump blood
- Endocaridum: INNER lining that lines the surface of the heart chambers
- Pericardium: Membranous sac surrounding the heart
four chambers of the heart
right side
pump is a LOW pressure system
-receives deoxygenated blood
pumps to lungs
four chambers of the heart
left side
pump is a HIGH pressure system
-receives oxygenated blood
-pumps to body
what does septum mean?
it separates the right and left sides of the heart
cardiac valves
direct the flow of blood through the heart chambers
the heart
(PMI)
the point of maximal impulse (PMI) can be felt between the fifth and sixth ribs , mid clavicular line
coronary arteries
supply the cardiac muscle(myocardium) with blood, oxygen, and nutrients
cardiac conduction
-sinoatrial (SA) node
- 60-100 bpm
- initiates electrical impulses
- pacemaker of the heart
cardiac conduction
-atriventricular (AV) NODE
- 4-60 bpm
- bundle of his
- right and left bundle braches
- purkinje fibers
systole
- contraction of heart muscle (SQUEEZE)
- blood ejects into the aorta
diastole
- relaxation of heart muscles (fill)
- ventricles fill with blood
the heart pumps out how many liters of blood every minute?
5L CARDIAC output
LUB
the sound of the mitral and tricuspid valves closing (S1)
DUB
the sound of the aortic and pulmonic valves closing (s2)
cardiac output
amount of blood the heart pumps each minute (5liters)
stroke volume
amount of blood ejected by the ventricle during one ontraction
ejection fraction
the percentage of blood that is ejected from the heart during systole
-a normal ejection fraction is 50% to 70%
arteries
carry oxygenated blood AWAY from the heart
Veins
carry deoxygenated blood back to the heart for deoxygenation by the lungs
capillaries
venues and arterioles are connected by the capillaries
systolic pressure
when blood is ejected into the aorta
diastolic pressure
pressure when the ventricles are in the relaxation phase
pulse pressure
the difference between systolic and diastolic BP
preload
blood pressure
the amount of stretch experienced by cardiac muscle cells at the end of ventricular filling during diastole
afterload
blood pressure
the pressure that the heart must work against to eject blood during systole
atherosclerosis
condition in which fibrous plaque with fatty deposits forms in the inner layers of the arteries, causing narrowing
electrocardiogram (EKG or ECG)
Records electrical impulses of heart- determines rate/rhythm/injury
holter monitor
EKG monitor over 24 + hours, records all activity
zio patch
same function as holder monitor, used more today than holder
EKG stress test
records electrical activity of heart during exercise
chemical stress test
records electrical activity after given drugs that increase cardiac workload; no exercise involved
ventilation- perfusion scan (V-Q SCAN)
checks ventilation/ perfusion in lungs; examine for blood clots (pulmonary emboli)
echocardiogram
ultrasound of Chets wall; determines EF, valve problems, size/shape of structures
cardiac cauterization
a catheter is advanced into the radial or femoral artery into the coronary arteries
-dye is injected to check for blockages
transesophageal echocardiogram (TEE)
endoscope placed in esophagus and positioned behind heart to obtain images
-NPO before procedures
electrophysiology studies
measures electrical activity, determines areas of organ of dysthymia's