Ventricular Arrhythmias

Ventricular ArrhythmiasVentricular Arrhythmias

EMS Professions

Temple College

Analyze the RhythmAnalyze the Rhythm

Premature Ventricular Premature Ventricular Complexes (PVCs)Complexes (PVCs)

Definitions Early depolarization of the ventricles Occur as a result of automaticity or reentry A PVC is a characteristic of an underlying

ECG rhythm PVC is not the name of a dysrhythmia

Premature Ventricular Premature Ventricular ComplexesComplexes

Causes Hypoxia Myocardial Ischemia Electrolyte Imbalance Digitalis Toxicity Stimulants Chronic Heart Disease (CHF, COPD)


Characteristics Complex is earlier than expected Wide QRS (wide is not always ventricular) OFTEN has a compensatory pause Usually irregular Not preceded by a P wave T wave opposite deflection May or may not result in perfused beat


More Terms to Know Unifocal, Multifocal R on T Phenomenon Bigeminy, Trigeminy, Quadrigeminy,

Couplet


PVCs are not always dangerous Common for some people Consider treating PVCs if:

>6/minute associated with: Severe Chest pain Hypotension, Decreased Perfusion Shortness of Breath


Treat PVCs if consistently see any of the following with other symptoms: Multifocal Ventricular Couplets Runs of Ventricular Tachycardia R on T Phenomenon (Malignant PVCs)


Management (Rate <60) Oxygen & Ventilation are initial treatments

for ALL ectopic beats ECG Monitor, IV NS TKO

assess the underlying rhythm

Treat like bradycardia Atropine TCP Dopamine


Management (Rate >60) Oxygen & Ventilation are initial treatments for

ALL ectopic beats ECG Monitor, IV NS TKO

assess the underlying rhythm

If symptomatic (see previous):


Management (Rate >60) Lidocaine

IV Bolus, 1 - 1.5 mg/kg Infusion, 1 - 4mg/min Repeat IV push 0.5 - 0.75 mg/kg every 5 minutes

to 3 mg/kg max Increase Infusion 1mg/min for every 1mg/kg IV

bolus given


Management (Rate >60) Procainamide

20 mg/min IV until: PVCs suppressed 17 mg/kg given Hypotension occurs QRS widens by 50% or more

Continuous infusion at 1 - 4 mg/min


Management (Rate >60) Bretylium

IV push, 5 mg/kg slowly Infusion, 1 - 2 mg/min Used less frequently today due to supply shortage

Idioventricular RhythmIdioventricular Rhythm

Causes Myocardial ischemia Hypoxia High vagal tone Drug effects


Characteristics A ventricular focus takes over as an escape

pacemaker site Rate 20 - 40 bpm Wide QRS complexes No P waves


Management Slow rate will probably decrease cardiac

output Usually a later and often pre-terminal rhythm If symptomatic, treat as unstable bradycardia Do NOT give Lidocaine or other ventricular

antidysrhythmics!!!!!!!

Accelerated Idioventricular Accelerated Idioventricular RhythmRhythm

Characteristics Like Idioventricular rhythm except for rate Rate, greater than 40 bpm but less than 100

bpm

Accelerated Idioventricular Accelerated Idioventricular RhythmRhythm

Management Patient may maintain adequate cardiac

output Identify underlying cause and treat!!! Monitor cardiac output and perfusion

Often a late and pre-terminal rhythm

Do NOT give Lidocaine or other antidysrhythmics!!!!!!!

Ventricular Tachycardia Ventricular Tachycardia (VT)(VT)

Causes Myocardial ischemia Hypoxia Electrolyte imbalance Digitalis toxicity Myocardial trauma


Characteristics Pacemaker site

Irritable ventricular focus takes over as pacemaker site, OR

May result from multiple ventricular foci attempting to become pacemaker site

Complexes look similar to PVCs May see P waves before complexes but uncommon Rate, usually between 100 and 250 bpm


Complications Can decrease cardiac output Increases cardiac workload Decreases coronary perfusion Can quickly deteriorate into V-fib


Types Monomorphic

QRS complexes all have same morphology

Polymorphic QRS complexes have more than one morphology

“Torsades de Pointes” “Twisting of the points” Usually > 200 bpm Susceptible if slow repolarization (long QT)

Ventricular Tachycardia (VT)Ventricular Tachycardia (VT)

Treatment of Stable and Unstable Oxygen, Ventilations, Assess Pulse ECG Monitor

If unstable, proceed to synchronized cardioversion

IV NS TKO Determine monomorphic vs polymorphic If wide complex of unknown origin, attempt 12

lead ECG to determine

Ventricular Tachycardia Ventricular Tachycardia Treatment: MonomorphicTreatment: Monomorphic

Treatment of Stable (limit to one antidysrhythmic) procainamide 20 mg/min IV

avoid if poor cardiac function

amiodarone 150 mg slow IV (15 mg/min) lidocaine 1.0 mg/kg IV (max 3.0 mg/kg)

Begin with 0.5 - 0.75 mg/kg poor cardiac function Follow with lidocaine infusion, 1 - 4 mg/min

synchronized cardioversion

Tachycardia: Wide Complex Tachycardia: Wide Complex (VT) Polymorphic (Torsades)(VT) Polymorphic (Torsades)

Treatment (limit to one antidysrhythmic) Normal QT

Lidocaine, 1 - 1.5 mg/kg IV (max 3.0 mg/kg), repeat @ 0.5-0.75 mg/kg q 5 min to max 3 mg/kg

Amiodarone, 150 mg slow IV (15 mg/min) Procainamide, 20 mg/min until

PVCs suppressed 17 mg/kg given Hypotension occurs QRS widens by 50% or more Then, infusion at 1 - 4 mg/min

Tachycardia: Wide Complex Tachycardia: Wide Complex (VT) Polymorphic (Torsades)(VT) Polymorphic (Torsades)

Treatment (limit to one antidysrhythmic) Long QT (including Torsades w/o arrest)

Magnesium sulfate 10%, 1-2 g slow IV over 5 mins or greater

Lidocaine, 1 - 1.5 mg/kg IV (max 3.0 mg/kg), repeat @ 0.5-0.75 mg/kg q 5 min to max 3 mg/kg

Other considerations phenytoin, isoproterenol, or overdrive pacing

Interesting QuestionsInteresting Questions

What is a capture beat?

What is a fusion beat?

How do they help or hurt you in your ECG interpretation?

Ventricular Arrhythmias

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