Ventricular Arrhythmias

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Ventricular Arrhythmias

• EMS Professions
• Temple College

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Analyze the Rhythm
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Analyze the Rhythm
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Analyze the Rhythm
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Premature Ventricular 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

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Premature Ventricular Complexes

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

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Premature Ventricular Complexes (PVCs)

• 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

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Premature Ventricular Complexes (PVCs)

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

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Premature Ventricular Complexes (PVCs)

• PVCs are not always dangerous
• Common for some people
• Consider treating PVCs if
• gt6/minute associated with
• Severe Chest pain
• Hypotension, Decreased Perfusion
• Shortness of Breath

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Premature Ventricular Complexes (PVCs)

• 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)

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Premature Ventricular Complexes (PVCs)

• Management (Rate lt60)
• Oxygen Ventilation are initial treatments for
  ALL ectopic beats
• ECG Monitor, IV NS TKO
• assess the underlying rhythm
• Treat like bradycardia
• Atropine
• TCP
• Dopamine

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Premature Ventricular Complexes (PVCs)

• Management (Rate gt60)
• Oxygen Ventilation are initial treatments for
  ALL ectopic beats
• ECG Monitor, IV NS TKO
• assess the underlying rhythm
• If symptomatic (see previous)

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Premature Ventricular Complexes (PVCs)

• Management (Rate gt60)
• 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

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Premature Ventricular Complexes (PVCs)

• Management (Rate gt60)
• 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

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Premature Ventricular Complexes (PVCs)

• Management (Rate gt60)
• Bretylium
• IV push, 5 mg/kg slowly
• Infusion, 1 - 2 mg/min
• Used less frequently today due to supply shortage

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Analyze the Rhythm
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Idioventricular Rhythm

• Causes
• Myocardial ischemia
• Hypoxia
• High vagal tone
• Drug effects

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Idioventricular Rhythm

• Characteristics
• A ventricular focus takes over as an escape
  pacemaker site
• Rate 20 - 40 bpm
• Wide QRS complexes
• No P waves

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Idioventricular Rhythm

• 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!!!!!!!

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Analyze the Rhythm
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Accelerated Idioventricular Rhythm

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

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Accelerated Idioventricular Rhythm

• 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!!!
  !!!!

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Analyze the Rhythm
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Ventricular Tachycardia (VT)

• Causes
• Myocardial ischemia
• Hypoxia
• Electrolyte imbalance
• Digitalis toxicity
• Myocardial trauma

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Ventricular Tachycardia (VT)

• 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

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Ventricular Tachycardia (VT)

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

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Ventricular Tachycardia (VT)

• Types
• Monomorphic
• QRS complexes all have same morphology
• Polymorphic
• QRS complexes have more than one morphology
• Torsades de Pointes
• Twisting of the points
• Usually gt 200 bpm
• Susceptible if slow repolarization (long QT)

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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

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Ventricular Tachycardia Treatment 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

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Tachycardia Wide Complex (VT) Polymorphic
(Torsades)

• Treatment (limit to one antidysrhythmic)
• Normal QT
• Lidocaine, 1 - 1.5 mg/kg IV (max 3.0 mg/kg),
  repeat _at_ 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

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Tachycardia Wide Complex (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 _at_ 0.5-0.75 mg/kg q 5 min to max 3 mg/kg
• Other considerations
• phenytoin, isoproterenol, or overdrive pacing

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Interesting Questions
What is a capture beat? What is a fusion
beat? How do they help or hurt you in your ECG
interpretation?