Cardiac Output Flashcards
Cardiac output definition
amount of blood pumped by the left ventricle in 1 minute
Heart rate definition
number of beats per minute
Stroke volume (SV) definition
amount of blood pumped out of a ventricle during each contraction
Stroke volume equation
EDV-ESV
Factors that affect heart rate
increased venous return, hormones,
Factors that affect stroke volume
changes in EDV and ESV
End diastolic volume (EDV) definition
amount of blood in ventricle at the end of diastole
What factors effect EDV
- amount of blood returning to the heart
- preload
- atrial contribution
- body position
- autonomic nervous system
End systolic volume (ESV) definition
amount of blood after ventricular contraction
What factors effect ESV
- strength of myocardial contraction
- afterload
- autonomic nervous system
- cardiac diseases
- hormones
What is the preload
degree of stretching in ventricular muscle cells during diastole
What is afterload
sum of all forces a ventricle must overcome before ejecting blood
What is the Frank-starling principle
stroke volume is equal to end diastolic volume; SV = EDV
the more the heart stretches, the harder it contracts
What is ventricular contractility
amount of force during contraction
ANS relationship with the heart
What is the cardiac reserve
difference between resting and maximal cardiac outputs
