David Roberts MSPAS RN PA-C - Mastering the 12-Lead EKG, Second Edition

Appendix

Rhythm Summary

SINUS RHYTHMS

Normal Sinus Rhythm

Regular rhythm

Rate of 60 to 100 beats/minute

QRS complexes are typically less than 100 ms duration

P waves are present and ALWAYS upright in leads I and II and inverted in aVR

Sinus Bradycardia

Regular rhythm

Rate less than 60 beats/minute

QRS complexes are typically less than 100 ms duration

P waves upright in leads I and II and inverted in aVR

Sinus Tachycardia

Regular rhythm

Rate greater than 100 beats/minute

QRS complexes are typically less than 100 ms duration

P waves are upright in leads I and II and inverted in aVR

Sinus Arrhythmia

Irregular rhythm, P-P varies by more than 0.16 second

QRS complexes are typically less than 100 ms duration

P waves are upright in leads I and II and inverted in aVR

SUPRAVENTRICULAR ARRHYTHMIAS

Premature Atrial Complex

The P wave occurs before the next P wave was due

The P wave has a different appearance than the P wave

After the PAC, there is often a small pause before the SA node resumes control

The QRS complex is usually identical to all other QRS complexes

AV Nodal Reentry Tachycardia (AVNRT)

Regular rhythm

Rate usually 140 to 220 beats/minute

QRS is typically narrow

P waves are often hidden in the QRS complex

WolffParkinsonWhite Syndrome

Short PR interval

Delta wave; slurred upstroke to start QRS

Prolonged QRS complex greater than 0.11 second

ST-T-wave discordance

Pseudo-infarction pattern

Paroxysmal Ectopic Atrial Tachycardia

Regular rhythm

Rate greater than 100 beats/minute

QRS complex is typically narrow (<0.12 second)

P wave has a different morphology than the sinus beat

Isoelectric baseline

Often sudden in onset and sudden stop

Multifocal Atrial Tachycardia/Wandering Atrial Pacemaker

Rhythm is irregularly irregular

MAT rate greater than 100 beats/minute

WAP rate less than 100 beats/minute

Narrow QRS complex

Three or more distinct P waves in a single lead

Isoelectric baseline

Atrial Escape Beat/Rhythm

Occurs after delay in sinus activity

P wave with different morphology than sinus beat, may be inverted

Rhythm is regular

Rate typically less than 60 beats/minute

Narrow QRS

PR interval greater than 0.12 second

Junctional Escape Beat/Rhythm

Occurs after delay in sinus activity

Rhythm is regular

Narrow QRS complex

P waves are absent or inverted immediately before or after QRS complex in lead II

PR is less than 0.12 second, when present

Atrial Fibrillation

Irregularly irregular ventricular response

Ventricular rate is commonly between 90 and 170 beats/minute

QRS complex is narrow

Absence of isoelectric baseline

No identifiable P waves

Atrial Flutter

May have regular or irregular ventricular response

Ventricular rate is commonly 140 to 160 beats/minute, but variable

Ventricular rate is a ratio of atrial rate, most commonly a 2:1 AV ratio

Narrow QRS complex

Flutter or sawtooth waves

Absence of isoelectric baseline

VENTRICULAR ARRHYTHMIAS

Premature Ventricular Complexes

No apparent P wave

Premature QRS complex

Wide QRS (>0.12 second)

Bizarre

ST-T-wave discordance

Compensatory pause

Monomorphic Ventricular Tachycardia

Three or more consecutive PVCs with same morphology

Regular rhythm

Rate greater than 120 beats/minute

Wide QRS

AV dissociation

Ventricular Fibrillation

Fibrillatory waves

Irregular

Rate 150 to 500 quivers/minute

Torsades de Pointes

Irregular rhythm

Rate 150 to 200 beats/minute

Gradual shift in both axis and amplitude of QRS complexes

QT prolongation was cause

Ventricular Escape Rhythm

Regular rhythm

No P waves

Wide QRS

Rate is 20 to 50 beats/minute

Accelerated Idioventricular Rhythm

Regular rhythm

Absence of P waves