Cardiac Rhythms

Question 1

How long should a P wave be?

Answer 1

2-3 small squares = 0.08 - 0.12 seconds

Question 2

How long should PR interval be?

Answer 2

3-5 small squares = O.12 -0.20

Question 3

How wide should the QRS complex be?

Answer 3

1.5 - 2.5 squares = 0.06 - 0.10 seconds

Question 4

6 Paris of ECG interpretation

Answer 4

1. Rate
2. Rhythm
3. P-waves
4. P-QRS marriage
5. QRS Complex
6. Name the strip

Question 5

Normal Sinus Rhythm

Answer 5

Rate - 60-100 bpm
Rhythm - regular
P- Wave - uniform and upright in lead 2, one precedes each QRS complex
PR interval - 0.12 (3 small squares) to 0.20 (5 squares) and constant
QRS - less then 0.12 (3 squares)

Question 6

Sinus Bradycardiac

Answer 6

Rate - less then 60
Rhythm - regular
P- Wave - uniform and upright in lead 2, one precedes each QRS complex
PR interval - 0.12 (3 small squares) to 0.20 (5 squares) and constant
QRS - less then 0.12 (3 squares)

Question 7

Sinus tachycardia

Answer 7

Rate - greater than 100 bpm but not usually greater than 150 bpm
Rhythm - regular
P- Wave - uniform and upright in lead 2, one precedes each QRS complex
PR interval - 0.12 (3 small squares) to 0.20 (5 squares) and constant
QRS - less then 0.12 (3 squares)

Question 8

Sinus arrhythmia

Answer 8

Rate - 60-100 bpm
Rhythm - irregular
P- Wave - uniform and upright in lead 2, one precedes each QRS complex
PR interval - 0.12 (3 small squares) to 0.20 (5 squares) and constant
QRS - less then 0.12 (3 squares)

Question 9

Sinus pause/arrest

Answer 9

Rate - 60-100 bpm usually but may vary depending on the length of the arrest
Rhythm - irregular because the arrest is of undetermined length
P Wave - upright in lead 2, one precedes each QRS complex
PR interval - 0.12 (3 small squares) to 0.20 (5 squares) and constant
QRS - less then 0.12 (3 squares)

Sinus Arrest = no P wave, no QRS, no T wave

Question 10

Premature Atrial Complexes (PAC)

Answer 10

• Ectopic (impulse that originate in a site other than the SA node) beats that originate within the atria and interrupt the normal rhythm
• an abnormal (non-sinus) P wave is followed by a QRS complex
• An extra beat or beats usually seen with a normal rhythm

Question 11

Multifocal Atrial Tachycardia/Wandering Atrial Pacemaker (Wandering Pacemaker)

Answer 11

Rate - Typically the heart rate is greater than 100 bpm (usually 100-150 bpm; may be as high as 250 bpm)
Rhythm - Irregularly irregular rhythm with varying PP, PR, and RR intervals
P- Wave - At least 3 distinct P-wave morphologies in the same lead with absence of a dominant pacemaker
PR interval - may be normal or may be variable. Some P waves may be non-conducted (P wave without a QRS complex. Some P waves may be aberrantly conducted to the ventricles.
QRS - less then 0.12 (3 squares)

Question 12

SVT (Supraventricular Tachycardia)

Answer 12

• often used synonymously with AV nodal re-entry tachycardia (AVNRT)
• can be used to refer to any tachydysrhythmia arising from the bundle of His
• different types of SVT arise from or are propagated by the atria or AV node, typically producing a narrow-complex tachycardia

Question 13

SVT refers to

Answer 13

Sinus Tachycardia
Atrial Flutter
Atrial Fibrillation
AVNRT

Question 14

AVNRT

Answer 14

Rate - 140-80 bpm
Rhythm - regular
P- Wave - buried in the QRS complex
PR interval - not measurable
QRS - less then 0.12 (3 squares)
Often referred to as (SVT)

Question 15

Wolf-parkinson white syndrome

Answer 15

Rate - 60-100 bpm
Rhythm - regular
P- Wave - uniform and upright in lead 2, one precedes each QRS
PR interval - 0.12 to 0.20 and constant or may be a bit shorter than normal
QRS Duration - usually greater than 0.12 (3 squares) slurred upstroke of the QRS complex called delta wave