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What are the two primary functions of the cardiovascular system?
1) Supply oxygen and nutrients
2) Remove carbon dioxide and wastes
What are the three required components of the cardiovascular system?
1) Heart
2) Vasculature
3) Regulatory Mechanisms
What are two important properties of the heart that are required for it to pump blood?
1) Volume-Cardiac Output (CO)
2) Pressure-Aterial Pressure (MAP)
What are the two regulatory mechanisms of the heart and what do they do?
1) Local:  each individual organ can regulate its own blood flow to an extent
2) Global:  global control
Where are action potentials generated in the heart and how are they generated?
Pace maker in SA Node through spontaneous depolarization
Does the heart need nerves to contract?
No
What are two special characteristics of action potentials in the heart?
1) Long action potential
2) No summation or tetanus
What are the two specialized conduction systems of the heart and why are they important?
1) Rapid (potential to all fibers)
Need synchronous contration essentially all at once
2) Fibrous tissue between atria and ventricles
AV Node has a delay which keeps atriums and ventricles from contracting at the same time
Is there recruitment of the fibers of the heart?
No, all fibers of the heart are recruited at the same time.
What is the pressure of the systemic circulation?
~120/80 mmHg
What is the pressure of the pulmonary circulation?
~25/8 mmHg
When do atrioventricular valves open and close?
Open-Pressure: Atrium > Ventricle
Close-Pressure: Ventricle > Atrium
When do semilunar valves open and close?
Open-Pressure: Ventricle > Aorta or Pulmonary
Close-Pressure: Aorta (Pulmonary) > Ventricle
What is systole?
Diastole?
Systole:  Contraction
Diastole:  Relaxation
In an ECG what does the following letters stand for:
1) P
2) QRS
3) T
1) Atrial depolarization
2) Ventricular depolarization
3) Ventricular repolarization
What occurs on an ECG during atrial systole?
P-wave (atrial depolarization)
What valves are open/closed during atrial systole?
Open: atrioventricular valves
Closed: semilunar valves
What are the three stages of ventricular systole?
1) Isovolumic contraction
2) Rapid ejection
3) Reduced ejection
What is "isovolumic" contraction?
Ventricle contraction with no corresponding volume change

Synonymous with "isovolumetric" and "isometric"
What occurs on an ECG during isovolumic contraction?
QRS (ventricle depolarization)
What valves are open/closed during isovolumic contraction?
Closed:  atrioventricular valve snaps shut
Closed:  Aortic valve still closed
What causes the first heart sound?
When the atrioventricular valve closes
What is happening to the atrium during an isovolumic contraction?
The atrium is still filling
What valves are open/closed during rapid ejection?
Open:  Semilunar valve
Closed:  Atrioventricular valve
What is the pressure of the aorta during rapid ejection?
120 mmHg
What occurs on an ECG during reduced ejection?
T-wave (ventricle repolarization)
What are the three stages of ventricular diastole?
1) Isovolumic relaxation
2) Rapid ventricular filling
3) Slower ventricular filling
What valves are open/closed during isovolumic relaxation?
Closed:  Semilunar valve closes
When does the 2nd heart beat sound occur?
During isovolumic relaxation
What is a dicrotic notch and when does it occur?
A slight increase in aortic pressure due to the closing of the semilunar valve
Occurs during isovolumic relaxation
Why is it important to have a rapid filling phase?
Diastole will shorten more than systole if heart rate needs to increase
What valves open/close during rapid ventricular filling?
Opened:  Atrioventriular valve opens
What is the equation for "stroke volume?"
Stoke volume = End Diastolic Volume - End Systolic Volume
SV = EDV - ESV
What are two ways to increase stroke volume?
1) Decrease End Systolic Volume
2) Increase End Diastolic Volume
What is the equation for "ejection fraction?"
Ejection Fraction = Stroke Volume/End Diastolic Volume
EF = SV/EDV
What is the equation for "Pressure-Volume Work?"
Pressure-Volume Work = Volume x Developed Pressure

P-V Work = Volume x (Mean Ejection Pressure - End Diastolic Pressure)
What type of metabolism does the heart use?
Aerobic (almost exclusively)
What are the four determinants of myocardial oxygen consumption (MVO2)?
1) Pressure
2) Radius
3) Inotropic State
4) Heart Rate
What are the four determinants of cardiac performance?
1) Preload
2) Afterload
3) Inotropic State
4) Heart Rate
What are the effects of increasing preload of the heart (afterload, contractility constant)?
Increase Stroke Volume
Increase End Diastolic Volume
What limits the effects of increasing preload of the heart?
Pulmonary edema
What effects do increasing the load have on muscle?
Rate of shortening decreases
Extent of shortening decreases
What are the effects of increasing afterload of the heart (preload, contractility constant)?
Decrease Stroke Volume
Increase End Systolic Volume
What are the effects of increasing contractility of the heart (preload, afterload constant)?
Increase Stroke Volume
Decrease End Systolic Volume
What is the equation for "Cardiac Output?"
Cardiac Output = Stroke Volume x Heart Rate
CO = SV x HR
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