Wide-complex tachycardia

Background

  • 3 wide complexes in a row is considered ventricular tachycardia
    • Non-sustained if lasts < 30 seconds
    • Sustained if lasts >30 seconds

Etiology[1][2][3]

  • Due to true ventricular tachycardia in 80% of cases
    • For patients with underlying cardiac disease, increases to > 90%
  • Consider:

Clinical Features

Differential Diagnosis

Narrow-complex tachycardia

Wide-complex tachycardia

Assume any wide-complex tachycardia is ventricular tachycardia until proven otherwise (it is safer to incorrectly assume a ventricular dysrhythmia than supraventricular tachycardia with abberancy)

^Fixed or rate-related

Evaluation

Ventricular tachycardia

Management

Wide Regular Tachycardia[4]

Pulseless: see Adult pulseless arrest

  • Unstable: Hypotension, altered mental status, shock, ischemic chest discomfort, acute heart failure
  • Stable:
  • Medications
    • Procainamide (first-line drug of choice)
      • 20-50mg/min until arrhythmia suppressed (max 17mg/kg or 1 gram); then, maintenance infusion of 1-4mg/min x 6hr
        • Alternative administration: 100 mg q5min at max rate of 25-50 mg/min[5]
      • Stop if QRS duration increases >50% or hypotension
      • Avoid if prolonged QT or CHF
      • Favored over Amiodarone in PROCAMIO trial; termination of tachycardia in 67% of procainamide group vs 38% of amiodarone group, adverse cardiac events 9% vs 41%, respectively [6]
    • Amiodarone (agent of choice in setting of AMI or LV dysfunction)
      • 150 mg over 10min (15 mg/min), followed by 1 mg/min drip over 6hrs (360 mg total)[7]
      • Then 0.5 mg/min drip over next 18 hrs (540 mg total)
      • Oral dosage after IV infusion is 400 -800 mg PO daily
    • Consider adenosine
    • Synchronized Cardioversion (100J)

Wide Irregular Tachycardia

DO NOT use AV nodal blockers as they can precipitate V-Fib
Pulseless: see Adult pulseless arrest

Recurrent

  • ≥3 episodes within 24 hours considered electrical storm and may require alternate treatment (i.e. beta blockade, sedation, ablation)

Other considerations

  • True Vtach generally has rate >120bpm. If rate <120bpm or refractory to other therapy, consider other causes
  • When in doubt, use cardioversion for treatment of regular WCT. In irregular WCT, consider Afib with WPW in which Procainamide is the treatment of choice
  • In very wide complex (>0.2 msec) and <120 bpm in a patient with significant history, consider giving calcium chloride to treat hyperkalemia
  • Consider Acidosis
  • Sodium channel blockade (e.g. from benadryl, TCA, or cocaine toxicity) may cause very wide complex (>0.2msec) tachycardia with rate <120bpm

Disposition

  • Admit all patients (even if converted to normal sinus rhythm in ED)

See Also

External Links

References

  1. Gupta AK, Thakur RK. Wide QRS complex tachycardias. Med Clin North Am. 2001;85(2):245–66– ix–x.
  2. Akhtar M, Shenasa M, Jazayeri M, Caceres J, Tchou PJ. Wide QRS complex tachycardia. Reappraisal of a common clinical problem. Ann Intern Med. 1988;109(11):905–912.
  3. Stewart RB, Bardy GH, Greene HL. Wide complex tachycardia: misdiagnosis and outcome after emergent therapy. Ann Intern Med. 1986;104(6):766–771.
  4. American Heart Association. Web-based Integrated Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care – Part 7: Adult Advanced Cardiovascular Life Support. ECCguidelines.heart.org
  5. Procainamide. GlobalRPH. http://www.globalrph.com/procainamide_dilution.htm.
  6. Ortiz M, Martín A, Arribas F, et al. Randomized comparison of intravenous procainamide vs. intravenous amiodarone for the acute treatment of tolerated wide QRS tachycardia: the PROCAMIO study. Eur Heart J. 2017 May 1;38(17):1329-1335
  7. Amiodarone. GlobalRPH. http://www.globalrph.com/amiodarone_dilution.htm.