EKG rhythms

Sinus Arrest

Asystole

PVC

V. Fib

Sinus tachycardia

PAC

Sinus bradycardia

A. Flutter

V tach

normal sinus

A. fib

PR interval

• measure from the beginning of the P wave to the beginning of the QRS

• normal is 0.12 to 0.20 seconds

QRS

• Ventricular depolarization and contraction

• normal 0/06 to 0.10 seconds

What does it mean if the PR interval is greater than 0.20 seconds

• delay

• blockage

What does it mean if the QRS is longer than 0.10 seconds?

• problems with ventricular conduction

ST segment

• beginning of ventricular repolarization

T waves

• represent ventricular repolarization

What causes abnormalities in the T waves?

• myocardial ischemia

• myocardial injury

• electrolyte imbalances

Medications that can prolong QT

• antiarrhythics/antidysrthmics

  • Amidarone

  • Norpace

  • Tikosyn

  • Procainamide

  • Quinidine

  • Sotalol

• antimicrobials/antifungals

  • Azithromycin

  • Clarithromycin

  • Erythomycin

  • Itraconazole

• psychotropics

  • Haldol

  • Thorazine

  • Tricyclics

• Droperidol

U wave

• not typically seen

• thought to be repolarization of the terminal purkinje fibers

• most commonly seen in hypokalemia

Rate: 60-100 bpm

P QRS: 1 to 1

PR interval: 0.12 to 0.20 seconds

QRS interval: 0.06 to 0.10 seconds

Regularity: regular

Treatment: none

• normal sinus rhythm

Rate: 101 to 151 bpm

P QRS: 1 to 1

PR interval: 0.12 to 0.20 seconds

QRS interval: 0.06 to 0.10 seconds

Regularity: regular

Treatment: treat cause

• sinus tachycardia

Rate: less than 60 bpm

P QRS: 1 to 1

PR interval: 0.12 to 0.20 seconds

QRS interval: 0.06 to 0.10 seconds

Regularity: regular

Treatment: if symptomatic treat cause (atropine, pacing)

• sinus bradycardia

Rate: 60 to 100 bpm

P QRS: 1 to 1

PR interval: 0.12 to 0.20 seconds

QRS interval: 0.06 to 0.10 seconds

Regularity: irregular

Treatment: none

• sinus arrhythmia

Rate: Variable

P QRS: 1 to 1

PR interval: 0.12 to 0.20 seconds

QRS interval: 0.06 to 0.10 seconds

Regularity: irregular

Treatment: none

• PAC’s (premature atrial contractions) and underlying rhythm

Rate: atrial 300 to 600 bpm

Rate: ventricular 100 to 18 bpm

P QRS: variable

PR interval: not measurable

QRS interval: 0.06 to 0.10 seconds

Regularity: irregularly irregular

Treatment: IV meds (digoxin, diltiazem, amiodarone), beta blockers, cardioversion, anticoagulants

• atrial fibrillation (A. Fib)

Rate: atrial 240 to 360 bpm

Rate: ventricular <150 bpm

P QRS: 2 to 1, 4 to 1, 6 to 1

PR interval: not measurable

QRS interval: 0.06 to 0.10 seconds

Regularity: atrial regular

Regularity: ventricles usually regular

Treatment: IV meds (digoxin, diltiazem, amiodarone), beta blockers, cardioversion, anticoagulants

• Atrial flutter

Premature ventricular contractions (PVCs)

• ectopic ventricular beats that occur before the next expected beat of the underlying rhythm

Frequent, recurrent, or multifocal PVCs indicate myocardial irritability and may precipitate?

• lethal dysrhythmias

Rate: 100 to 250 bpm

P QRS: no P waves

PR interval: not measurable

QRS interval: >0.12 seconds, bizarre shape

Regularity: regular

Treatment: stable = lidocaine, cardioversion = unstable, defibrillation = no pulse

• ventricular tachycardia (VT)

Rate: too fast to count

P QRS: no P waves

PR interval: not measurable

QRS interval: not measurable

Regularity: irregular

Treatment: Defibrillation

• ventricular fibrillation (VF, V-Fib)