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Ventricular Tachycardia Management in the Adult
Aka: Ventricular Tachycardia Management in the Adult, Torsades de Pointes, Torsades
- See Also
- Ventricular Tachycardia Management in the Child
- Unstable Tachycardia
- Narrow Complex Tachycardia
- Wide Complex Tachycardia
- Indications: Wide Complex Tachycardia in Adults
- Tachycardia (typically >150 bpm) AND
- Wide QRS Complex (duration at least 0.12 sec)
- Precautions: SVT with aberrancy
- Manage Wide Complex Tachycardia as Ventricular Tachycardia
- Algorithms (e.g. Griffith, Brugada, Bayesian) are inadequate
- Cannot distinguish VT from SVT with aberrancy (or RBBB) - miss rates of 6-7% at best
- Jastrezbski (2012) Europace 14(8): 1165-71 [PubMed]
- Szelenyi (2013) Acad Emerg Med 20(11): 1121-30 [PubMed]
- Consequence of treating Ventricular Tachycardia as SVT (e.g. with Calcium Channel Blocker) can be lethal
- In contrast, treating SVT with aberrancy with an Antiarrhythmic (e.g. Procainamide) is unlikely to cause harm
- Adenosine use in Wide Complex Tachycardia is also controversial
- Ventricular Tachycardia will convert to sinus rhythm with Adenosine in 5-10% of cases
- Conversion with Adenosine leads to incorrect conclusion that the underlying rhythm was SVT with aberrancy
- May result in missed VT diagnosis
- Misses associated telemetry admission, Antiarrhythmics and electrophysiology evaluation
- Amal Mattu recommends not using Adenosine in Wide Complex Tachycardia
- Risk of masking potentially lethal VT in up to 10% of cases
- References
- Mattu in Herbert (2014) EM:Rap 14(7): 4-5, 13-14
- Approach: General
- ABC Management with IV-O2-Monitor is paramount in all cases
- No pulse
- Treat as Pulseless Ventricular Tachycardia
- Unstable (Hypotension, ALOC, ischemic Chest Pain or acute CHF)
- Treat as Unstable Ventricular Tachycardia
- Administer Synchronized Cardioversion
- Stable
- Assess QRS Complex morphology
- Treat per protocols below
- Monomorphic Ventricular Tachycardia
- Polymorphic Ventricular Tachycardia
- Approach: Wide Complex Tachycardia (key question is 'regular or irregular')
- Unstable Wide Complex Tachycardia
- Synchronized Cardioversion (or asynchronized, Defibrillation if not responding)
- Stable Wide Complex Tachycardia (see each approach described in sections below)
- Irregular Wide Complex Tachycardia
- Regular Wide Complex Tachycardia
- Approach: Irregular Wide Complex Tachycardia (stable)
- Polymorphic Ventricular Tachycardia
- INITIAL Steps
- Immediate Defibrillation (non-Synchronized Cardioversion)
- Differentiation based on QT Interval is directed at prevention of recurrent Arrhythmia
- Prolonged QT interval (on baseline EKG): Torsades de Pointes
- Give Magnesium 2 grams IV
- May be repeated in 5-15 minutes
- May be continued as infusion Magnesium 3 to 20 mg/min IV for Prolonged QTc
- Correct other Electrolyte abnormalities (5H5T)
- Stop all medications that prolong QT Interval
- Reverse toxic ingestions and Poisonings
- Consider overdrive pacing to Heart Rate of 100 bpm
- Avoid Isoproterenol (used historically)
- Normal QT Interval (on baseline EKG)
- Myocardial Ischemia (most common)
- Beta Blockers
- Emergent cardiac catheterization for revascularization
- Consider Amiodarone 150 mg IV
- Catecholaminergic Ventricular Tachycardia
- Consider Beta Blockers
- Brugada Syndrome
- Consider Isoproterenol
- Pre-excited Atrial Fibrillation (antegrade conduction via accessory pathway, e.g. WPW)
- Avoid AV Nodal blockers (Beta Blockers, Diltiazem, Verapamil, Digoxin, Adenosine)
- Consult with local experts
- Rapid Heart Rate typically requires electrical cardioversion
- Consider Amiodarone 150 mg IV
- Atrial Fibrillation with aberrancy
- Treat as Narrow Complex Tachycardia only if can rule-out pre-excited Atrial Fibrillation
- Approach: Regular Wide Complex Tachycardia (stable)
- INITIAL: Adenosine (or go to below under Ventricular Tachycardia)
- AVOID if polymorphic or irregular Wide Complex Tachycardia (can degenerate to VF)
- Some experts recommend avoiding Adenosine in all cases of Ventricular Tachycardia (see precautions above)
- Dose: 6 mg IV (may repeat with up to two 12 mg IV doses)
- Effect
- SVT (or aberrancy): converts or at least slows rhythm for interpretation
- VT: no effect (unless irregular, in which case could degenerate into VF)
- Ventricular Tachycardia (assume until proven otherwise)
- Synchronized Cardioversion if unstable or refractory to measures below
- Recommended agents for chemical cardioversion
- Procainamide
- Preferred if not contraindicated
- Zipes (2006) Circulation 114(10): e385-484 [PubMed]
- AVOID in Prolonged QT or CHF
- Loading Dose 50 mg/min
- Target: Until successful, Hypotension, or QRS widens >50%
- May slow rate to 20 mg/min (or stop and restart slowly) if QRS Widening or QT Prolongation occurs during infusion
- Maximum: Cummulative dose 17 mg/kg (or ~1 gram)
- Maintenance: 1-4 mg/min
- Post-cardioversion Antiarrhythmic infusion may be replaced with Beta Blocker instead (see below)
- Amiodarone
- Preferred in CHF or Prolonged QT (but effective in only 20% of cases)
- Dose 150 mg IV over 10 minutes
- Maintenance: 1 mg/min for 6 hours
- Post-cardioversion Antiarrhythmic infusion may be replaced with Beta Blocker instead (see below)
- Sotalol
- AVOID in Prolonged QT
- Dose 1.5 mg/kg up to 100 mg over 5 minutes
- Post-Cardioversion (chemical or electrical) management
- Beta Blocker (Metoprolol or Esmolol)
- Consider starting after successful cardioversion (not before due to negative inotropy)
- Suppresses Ventricular Tachycardia associated Catecholamine surges
- Consider in place of Antiarrhythmic infusions listed above
- References
- Mattu in Majoewsky (2013) EM:Rap 13(9): 7
- Cardiopulmonary Resuscitation Guidelines
- http://www.circulationaha.org
- (2010) Guidelines for CPR and ECC [PubMed]
- (2000) Circulation, 102(Suppl I):86-9 [PubMed]