Module 4 Flashcards
What is cardiac output?
The volume of blood ejected by the heart each minute
What is pre-load?
resting force of the myocardial muscle and is determined by the volume in the ventricle prior to contraction
What is Frank-Sterling law of the heart?
The greater the heart is filled during diastole, the greater the quanity of blood is pumped into the aorta
What is afterload?
is the force that the ventricles must overcome in order to contract and eject its blood
What does a high afterload cause?
The heart has to work harder and under greater strain
What drugs help decrease afterload?
Vasodilators decrease afterload, thus improving stroke volume and cardiac output
What coronary arteries originate off the aorta?
left and right coronary arteries
What coronary arteries branch off the left CA?
circumflex and left anterior descending branch
What coronary arteries branch off the right CA?
posterior descending artery
The circumflex artery supplies what part of the heart?
left posterior side
The left anterior descending artery supplies what part of the heart?
left anterior side
The posterior descending artery supplies what part of the heart?
Right ventricle
The right coronary arteries supply what part of the heart?
right anterior and posterior
What is the underlying rate of the SA node?
60-100 BPM
What is the underlying rate of the AV node?
45-50 BPM
What is the underlying rate of the bundle of HIS
40-45 BPM
What is the underlying rate of the purkinje fibers?
30-40 BPM
What is the pathway of an impulse through the heart
SA node –> AV node –> bundle of his –> Left and right bundle branches
What heart rhythms arise from issues with the SA node?
Sinus tachycardia and bradycardia
1st degree AV block
What heart rhythms arise from issues with the atria?
Atrial tachycardia, flutter and fibrillation
What heart rhythms arise from issues with the ventricles?
V-Fib, V-tach, PVC’s (more the ventricular myocardial cells)
What heart rhythms arise from issues with the AV node?
Premature junctional beats, 1st, 2nd, 3rd degree AV blocks