Chapter 2: Cardiovascular System Flashcards
Action Potential
a rapid sequence of changes in the voltage across a membrane
AV Node
electrical relay Station between the upper and lower Chambers of the heart.
Atrium
one of the 2 upper Chambers in the heart that recieves blood from the circulatory System
Automaticity
the property of Cardiac cells to generate Spontaneous action potientals
Bachmann’s Bundle
a musclar bundle composed of parallel muscle Strands connecting the left & right atria & serving as the primary electrical connection between lert and right atria
Bundle Branches
Offshoots of the bundle of His in the hearts ventricles.
Bundle of His (AV bundle)
an elongated segment connecting the AV node and Left and right bundle branches of septal crest
Complexes
atrial or ventricular contractions as they appear on ECG; complete ECG wave forms.
Conductivity
the capicity of a compound to convey energy like Skin, thermal, or electrical conduction.
Contractility
the ability of the heart to eject a Stroke volume at a given arterial pressure and preload
coronary Circulation
the movement of blood throughout the vessels that supply the myocardium (heart muscle).
Depolarization
when change occurs within a Cell that causes the distribution of electric charges to alter leaving the cell with a less negative charge than the outside
Diastole
when the heart muscle relaxes and the Filling or chambers with blood.
Excitability
allowing the cell to respond to Stimulation by rapid changes in membrane potential produced by ion fluxes across the plasma membrane
Interval
The period of time between two activites within the heart.
Ischemia
a condition in which blood flow is restricted or reduced in a part of the body.
Isoelectric
relating to or being a Flatline on an electrophalogram lndicating a lack of electrical brain activity.
Parasympathic
a network of nerves that relaxes your body arter periods or stress or danger.
Pericardium
a membrane, or sac the surrounds your heart.
Polarization
a membrane that has a positive electrical charge on one side and negative on another side.
Purkinje Fibers
Specialized conducting fibers composed of electrically excitable cells.
Purkinje Network
a crucial component in electrical excitation of human heart
Repolarization
the process of restoring the polarized condition across the plasma membrane of a Cell.
Segment
a portion of a larger body, set off by natrual established boundaries.
SA Node
generates an electrical signal that causes upper chambers to contract.
Sympathetic
a network or nerves that helps your body activate It “flight or fight” response
Systemic Circulation
the circut of vessels supplying oxgenated blood to and returning deoxygenated blood from the Tissues.
Systole
period of contraction of the ventricle of the heart that occurs between the first & second heart Sounds of the cardiac cycle.
Cardiac Septum
a wall of tissue that elivicles the right and left sides or the heart.
Interartial septum
the portion of the Cardiac septum which divides ine right + left atria.
What do the different sides of ventricles do?
the left pumps blood to the whole body while the right pumps only to the lungs.
Pericardium
fluid sac the provide lubrication for the heart and helps to protect from lnfection & tramua
What are the 3 different layers of the heart?
Outer layer-Epicardium
Middle layer- Myocardium
Inner Layer- Endocardium
What are the functions of the heart?
pumps bloods, Supplies nutrients and oxygen, Removes carbon dioxide and waste.
What does Circulation depend on?
electrical activity of the heartand the ability of the hear t to contract.
What is the average beats per minute for heart?
72 beats per min
What is the average and total output of the heart?
Average: 70 ml
Total: 52 per min
periadal
tough outer layer or the pericardium.
Visceral
(epicardium) adheres closely to the heart.
Percardial Space
between the parietal and the viser al layers of the heart and contain 10-20 fluid and purpose to Cushion heart against tramua
Epicardium
contains coronary arteries.
Myocardium
the muscular layer
Endocardium
lines the inner Surfaces of the heart chambers and the valves.
Stroke volume
the amount or blood ejected with each contraction.
blood Volume increases heart rate decreases
What varies Stroke volume?
gender size, physical fitness, disease and genetics.
What are the signs and symptoms of low cardiac output?
Pale, confusion, Low BP, complain of nausea, & dizziness.
equation for Cardiac Output
HR×SV =CO
Sympathetic branch
secretes norepinprine, increases the HR & contractiblity
Parasympathetic
Secretes acetylcholine, decreases HR by stimulating vagnus nerve
What are the factors of HR?
Excercise, stress, Body temperature, Blood pressure, and electrolight levels
potassium
not enough- HR decreases
Too much-cause dysrhythmias
calcium
Not enough-depress heart activity
Too much-longer heart contraction
Pathways of conduction
SA Node- Bachmann’s Bundle-AV Node- Bundle of His-Bundle Branches- Purkinje fibers.
Atrial Kick
addtional blood that travel from the atria to the ventricles before they contract as a electrical delay caused by the AV Node.
ECG Waveform
Recorded depolarization and repolarization, isoelectric line/ baseline.
What are the elements of a ECG Waveform ?
P, Q, R, S, T waves
QRS complex, PR interval, QT interval.
