CV Physiology Flashcards
Equation for cardiac output
Cardiac Output = stroke volume * heart rate
Mean arterial pressure (MAP) equation
MAP = cardiac output * total peripheral resistance
Pulse pressure equation
PP = systolic pressure - diastolic pressure
(therefore you’d get LESS pulse pressure in anything that increases compliance (like sepsis) and decreases stroke volume (like heart failure))
Does DECREASED extracellular Na+ increase or decrease contractility?
Increase (because less Na+ OUT means that the Na+/Ca+2 pump will work LESS, and thus less Ca+2 will be pumped out)
Which way does the cardiac Na+/Ca+2 usually go?
Na+ IN
Ca+2 OUT
Preload depends on _________ tone.
Venous (thus vEnodilators decrease prEload)
How does the heart compensate for long-standing HTN?
Concentric left ventricular hypertrophy
What is the measurable difference between systolic and diastolic HF (not symptoms)?
ejection fraction
EF decreases in SYSTOLIC HF whereas normal in diastolic HF
What is normal EF?
55%
Ohm’s law for the heart
change in pressure = flow * resistance
___________ have the highest toal cross-sectional area and lowest flow velocity.
Capillaries
_____________ depends mostly on hematocrit but can increase in hyperproteinemic states.
Viscosity
What accounts for most of the total peripheral resistance?
arterioles (they still have muscle of them!)
What provides most of the blood storage capacity?
Veins
Pressures in all four heart chambers, aorta, and pulm artery.
RA: <5 RV: 25/5 Pulm artery: 25/10 LA: <10 LV: 120/10 Aorta: 120/80
