Coronary Blood Supply
Which vessel supplies the anterior wall?
Left Anterior Descending
The heart is under control of what nervous system?
Autonomic Nervous System
What are 4 primary characteristics of cardiac cells?
1. automaticity
2. excitability
3. conductivity
4. contractility
First deflection of the cardiac cycle, caused by depolarization of right and left atria
p wave
How many seconds is the normal PR interval?
0.12 - 0.20 seconds
Which vessel supplies the septal wall?
Septal branch of the Left Anterior Descending
Stimulation of the Sympathetic nervous system results in the release of what?
Norepinephrine
What does automaticity do specific to the heart?
spontaneously generate electrical impulses
The time from the onset of atrial depolarization to the onset of ventricular depolarization.
PR interval
less than 0.12
Which vessel supplies the lateral wall?
Left Circumflex
Stimulation of the Parasympathetic Nervous System results in the release of what neurotransmitter?
Acetylcholine
What does excitability do specific to the heart?
Respond to specific stimulus
Represents depolarization of right and left ventricles
QRS
What rhythm has a heart rate of less than 60
Sinus bradycardia
Which vessel supplies the inferior wall?
What response to alpha 1 receptors have on the heart?
increase vascular smooth muscle contraction
What does conductivity do specific to the heart?
conduct electrical activities to adjacent cardiac cells
The flat line between the QRS and T wave. Normally positioned on the isoelectric line
ST segment
Sinus tachycardia
Which vessel supplies the posterior wall?
Posterior descending branch
What response do beta 2 receptors have on the heart?
Vasodilation and bronchodilation
What does contractility do specific to the heart?
Cause cardiac muscle contraction
Represents ventricular repolarization
T wave
Which of the sinus rhythms is irregular?
Sinus arrhythmia