ECG

What features make cardiac cells

different than other cells in the body?

• automaticity

• excitability and conductivity

• contractility

• all of the above

Which is the primary cardiac pacemaker?

• atrio-ventricular node

• junctional node

• sino-atrial node

• Purkinje fibers

When electrical stimulation spreads

throughout the heart, this is known a

• automaticity

• depolarization

• repolarization

• cardiogenic shock

After contraction, the cardiac cells return

to resting state. This process is called

• depolarization

• repolarization

• asystole

• pulseless electrical activity

The smallest box on an ECG strip

represents how much time?

• 0.02 seconds

• 0.04 seconds

• 0.2 seconds

• 0.4 seconds

The big box on an ECG strip represents

how much time?

• 0.02 seconds

• 0.04 seconds

• 0.2 seconds

• 0.4 seconds

A PR interval is usually how long?

• 0.04 – 0.12 seconds

• 0.12 – 0.2 seconds

• > 0.2 seconds

• 1 second

The inherent pacing rate for the SA node

is usually

• 20-40 bpm

• 40-60 bpm

• 60-100 bpm

• >100 bpm

The hallmark sign of sinus bradycardia is

• PR interval > 0.20 seconds

• HR < 60 bpm

• HR > 100 bpm

• absent P waves

The hallmark sign of atrial flutter is

• short, jagged, irregular P waves

• sawtooth-appearing P waves

• tombstone-appearing waves

• missing P waves