Cardiovascular Anatomy Flashcards
Describe Phase 0 of the cardiac cycle
Describe Phase 1 of the cardiac cycle
Describe Phase 2 of the cardiac cycle
Describe Phase 3 of the cardiac cycle
Describe Phase 4 of the cardiac cycle
Which current is the primary determinant of SA node rate?
the funny current I-f
The SA node action potential has three phases:
What is “funny” about the funny current?
It’s activated by hyperpolarization, no depolarization
We can increase the heart rate by altering one of three variables:
- The slope of phase 4 increases
- The threshold potential becomes more negative
- The resting potential becomes less negative
How does SNS stimulation effect heart rate?
Decreases the slope of phase 4 by increasing Na and Ca conductance
How does PNS stimulation effect heart rate?
Increases the slope of phase 4 by increasing K conductance and lowering the resting membrane potential
What is the calculation for CaO2?
What is the calculation for DO2?
What is a normal VO2?
Approx. 250ml/min
OR
3.5ml/kg/min
How does vessel radius impact flow?
How does Reynold’s Number correlate with flow?
Flow through a vessel is described by which law?
Ohm’s Law
Flow= P. Gradient /Resistance
How can you calculate the MAP from CO, CVP, and SVR
How does the Law of Laplace apply to myocardial wall stress?
What is diastasis?
The middle third of diastole