| Question |
Answer |
| Cardiac Output | volume of blood pumped by each ventricle per minute |
| Stroke Volume | Volume of blood ejected per beat |
| Heart Rate | Number of heart beats/minute |
| Cardiac Output Equation | CO = HR x SV |
| Stroke Volume Equation | SV = EDV - ESV |
| Schematic for the SV component of the Equation | Preload (Starling Effect)
Contractility
Afterload
Compliance |
| Ejection Fraction | EF = (SV)/(EDV) |
| Inotropy | contractility |
| Starlings Law | As volume increases, length increases and the greater the contraction |
| Compliance Equation | (delta)V/(delta)P |
| Increasing Preload causes | Increasing EDP
Increasing EDV
Increases SV and CO |
| Decreased HR causes | less time for filling and results in a lesser force |
| Afterload | force it has to overcome (arterial pressure) |
| Increasing Afterload | Increases pre-ejection pressure
Increases ESV
Decreases SV and CO |
| Increasing contractility | Decreases ESV
Increases SV |
| Lowering Compliance | decreased EDV
Decreases SV and CO |
| length affects | tension and velocity |
| Ejection Fraction in normal health | 55% |
| What is the only way to change the slope of the left ventricular pressure | change contractility |
| What affects contractility? (3) | Positive inotropic effects
|
| Postive inotropes caused by | open Ca channels
inhibition of the Na/Ca exchanger
Inhibit plasma membrane pump
Activations of B1 receptors |
| what cardiac drug induces positive inotropic effects? | Cardiac glycosides (digitalis) |
| Negative inotropes | Ca channel blockers
Low Ca
High extracellular Na |
| Determinants of O2 demand on the heart | afterload
extent of muscle shortening
heart rate
inotropic state
heart size |
| 60-90% of cardiac ATP derived from ________ | free fatty acids |
| Calculating CO using the Fick Principle: | "oxygen is the indicator" |
| Cardiac Output equation using Fick Principle | CO = O2 consumption / (O2 pulmonary vein - )2 pulmonary artery) |
Biology Lab Midterm
