ACLS: Tachycardia

3 questions

1. Is the patient in a sinus rhythm?
2. Is the QRS wide or narrow?
3. Is the rhythm regular or irregular?

Narrow complex tachycardia

Algorithm for tachycardia with a pulse (Adapted from ACLS 2010)

Narrow Regular Tachycardia

• Sinus tachycardia
  • Treat underlying cause
• SVT
  • Vagal maneuvers (convert up to 25%)
  • Adenosine 6mg rapid IV push if patient hemodynamically stable (unstable should proceed directly to electrical cardioversion)
    • Can follow with repeat dose of 6 mg or 12mg if initially fails
    • If adenosine fails, initiate rate control with calcium channel blocker or beta blocker or use synchronized cardioversion
      • Diltiazem 15-20mg IV, followed by infusion of 5-15mg/hr
      • Metoprolol 5mg IVP x 3 followed by 50mg PO
  • Synchronized cardioversion (50-100J)
    • Provide sedation prior to synchronized cardioversion if patient is hemodynamically stable
• Atrial flutter
  • Stable: Consider rate control to HR < 110 bpm
  • Unstable: Synchronized cardioversion; start at 50J

Narrow Irregular Tachycardia

• Multi-focal atrial tachycardia (MAT)
  • Treat underlying cause (hypokalemia, hypomagnesemia)
  • Consider diltiazem
  • Avoid beta blockers unless they are already known to be tolerated, as airway disease often co-morbid
  • If not symptomatic and rate < 110/120 bpm, may not require treatment (e.g., patient with MAT secondary to COPD)
• Sinus tachycardia with frequent PACs
  • Treat underlying cause
• A fib / A Flutter with variable conduction (see also Atrial Fibrillation with RVR)
  • Check if patient has taken usual rate-control meds
    • If missed dose, may provide dose of home medication and observe for resolution
  • Determine whether patient is better candidate for rate control or rhythm control
    • Rate control preferred with:
      • Persistent A fib
      • Less symptomatic patients
      • Age 65 or older
      • Hypertension
      • No heart failure
      • Previous failure to cardiovert
      • Patient preference
    • Rhythm control preferred with:
      • Paroxysmal or new A fib
      • More symptomatic patients
      • Age < 65 years
      • Heart failure clearly exacerbated by A fib
      • No history of rhythm control failure
      • Patient preference
  • Rate control with:
    • Diltiazem
    • Metoprolol
    • Amiodarone (good in setting of hypotension, CHF)
    • Digoxin (good in setting of CHF)
  • Rhythm conversion with:
    • Synchronized Cardioversion (120-200 J)
      • Best performed on patients with new onset A fib or patients fully therapeutically anti-coagulated for > 3 weeks
    • Procainamide per Ottawa Aggressive ED Cardioversion Protocol

Wide complex tachycardia

ACLS: Wide Regular Tachycardia

• If pulseless: shock (unsynchronized 200J)
  • See Adult Pulseless Arrest
• If unstable: shock (synchronized 100J)
  • Hypotension, altered mental status, shock, ischemic chest discomfort, acute heart failure
• If stable:
  • Meds
    • Procainamide
      • 20-50mg/min; then maintenance infusion of 1-4mg/min x6hr
      • Treat until arrhythmia suppressed, QRS duration increases >50%, hypotension, Max 17mg/kg or 1 gram
      • Avoid if prolonged QT or CHF
    • Amiodarone
      • 150mg over 10min (repeat as needed); then maintenance infusion of 1mg/min x6hr
    • Adenosine
      • May be considered for diagnosis and treatment only if rhythm is regular and monomorphic
  • Synchronized Cardioversion (100J)

ACLS: Wide Irregular Tachycardia

DO NOT use AV nodal blockers as they can precipitate V-Fib

1. A fib with preexcitation
   • 1st line - Electric Cardioversion
   • 2nd line - Procainamide, amiodarone, or sotalol
2. A fib with aberrancy
3. Polymorphic V-Tach / Torsades De Pointes
   • Give IV MgSO4
   • Emergent defibrillation (NOT synchronized)
   • Correct electrolyte abnormalities (esp hypoK, hypoMg)
   • Stop prolonged QT meds

See Also

• ACLS (Main)
• Wide complex tachycardia
• Narrow complex tachycardia
• SVT
• PALS: Tachycardia

External Links

• DDxOf: Simplified ACLS Algorithms