Cardiac Conduction
This structure is the normal pacemaker of the heart.
Answer: What is the SA node?
The ability of cardiac cells to generate their own electrical impulse.
Answer: What is automaticity?
This wave represents atrial depolarization.
Answer: What is the P wave?
This mechanical event occurs during the P wave.
Answer: What is atrial contraction (atrial kick)?
Normal sinus rhythm has a heart rate between these two numbers.
Answer: What is 60–100 bpm?
This structure delays electrical conduction by approximately 0.12 seconds.
Answer: What is the AV node?
The ability of a cardiac cell to respond to a stimulus.
Answer: What is excitability?
This complex represents ventricular depolarization.
Answer: What is the QRS complex?
This phase immediately follows ventricular depolarization.
Answer: What is isovolumic contraction?
A sinus rhythm with a heart rate below 60 bpm.
Answer: What is sinus bradycardia?
This bundle is the only normal electrical connection between the atria and ventricles.
Answer: What is the Bundle of His?
The Frank-Starling Law describes this myocardial property.
Answer: What is contractility?
This wave represents ventricular repolarization.
Answer: What is the T wave?
During this phase all four cardiac valves are closed immediately after systole.
Answer: What is isovolumic relaxation?
A sinus rhythm with a heart rate greater than 100 bpm.
Answer: What is sinus tachycardia?
This structure allows electrical conduction to rapidly spread between adjacent cardiac myocytes.
Answer: What are intercalated discs?
The ability of cardiac cells to pass an impulse from one cell to another.
Answer: What is conductivity?
This wave represents ventricular repolarization.
Answer: What is the PR interval?
This ventricular filling phase occurs as the ventricles relax and blood rapidly enters from the atria.
Answer: What is the E-wave?
A normal sinus rhythm should have this P:QRS ratio.
Answer: What is 1:1?
Name the conduction pathway in order from beginning to end.
Answer: What is SA node → Bachmann's Bundle/Internodal Tracts → AV node → Bundle of His → Right & Left Bundle Branches → A&P Fascicles -->Purkinje Fibers?
Which pacemaker tissue has the lowest automaticity threshold?
Answer: What is the SA node?
Which electrical event cannot normally be visualized because it occurs during the QRS complex?
Answer: What is atrial repolarization?
During which mechanical event does the AV node delay conduction?
Answer: What is the A-wave (atrial contraction)?
To qualify as a normal sinus rhythm, the PR interval should measure within this range.
Answer: What is 0.12–0.20 seconds?