1/19
Looks like no tags are added yet.
Name | Mastery | Learn | Test | Matching | Spaced |
---|
No study sessions yet.
What system controls the heart rate ?
Autonomic nervous system
What does the autonomic nervous system do ?
self governing , control involuntary ( subconscious) activities of internal muscles and glands
Cardiac muscle
Myogenic : self contracting , generates its won electrical impulses
Contraction is caused by electrical impulses, traveling across the muscle
Atrial muscle contacts at a higher or lower frequency then ventricular muscle ?
Slightly higher ( more often )
What is fibrillation ?
Due to the muscle is myogenic, if it is to carefully coordinated it could lead to fibrillation
What are the cells that generates electrical impulses ?
Dino atrial node ( SAN ) - pacemaker cells
Generates electrical impulses, controls frequency of heartbeat
What is the other phase for electrical impulse ?
Wave of excitation
How does the electrical impulse travel through the heart ?
1) SAN sends impulse over atrial muscle as ‘ wave of excitation ‘
2) Atrioventricular septum is non - conductive , it prevents the impulse from traveling down over the ventricle walls.
3) The impulse pauses at the AVN, allowing time for the atria to fully contract and empty the blood into the ventricles , before the ventricles contracts.
4) Impulse travel down bundle of his the though purkinje fibers over ventricle muscle
What is a ECG ?
Electrocardiogram
What are the uses of ECG ?
Shows the electrical activity of the heart during one cardiac cycle
Draw a graph of one heartbeat ?
What does P mean ?
Excitation of atria
What does QRS mean ?
Excitation of ventricle
What does T mean ?
Diastole
What does this trace show ?
Normal trace , sinus rhythm
What does this trace show ?
Bradycardia, slow heart rate
What does this trace show ?
fast Heart rate , Tachycardia
What does this trace show ?
Atrial Fibrillation
What does this trace show ?
Ectopic heartbeat , single heartbeat is out of rhythm