Electrical storm
Background
- Definition: 3 or more episodes of sustained ventricular tachycardia, ventricular fibrilation, or ICD shocks within 24 hours
- Most have underlying structural heart disease, but also seen in those with structurally normal hearts (i.e. Brugada syndrome, Long QT syndrome)
- Type 2 Diabetes is protective
Risk factors [1]
- CAD
- HFrEF
- QT prolongation
Causes
- Ischemia
- Electrolyte derangement
- Iatrogenic (i.e. QT prolonging medications)
- Hyperthyroidism
- Infection/Fever
- Brugada syndrome
- Short QT syndrome, long QT syndrome
- Early repolarization syndrome, especially in inferior leads
Clinical Features
- Presentation as:
- Cardiac arrest
- Palpitations
- (Pre)Syncope
- ICD patient complaining of shock(s)
- Type of Ventricular Arrhythmias [2] [3]
- Monomorphic VT 86-97%
- Primary VF 1-21%
- Mixed VT/VF 3-14%
- Polymorphic VT 2-8%
Differential Diagnosis
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)
- Regular
- Monomorphic ventricular tachycardia
- PSVT with aberrant conduction:
- PSVT with bundle branch block^
- PSVT with accessory pathway
- Atrial flutter with bundle branch block^
- Sinus tachycardia with bundle branch block^
- Accelerated idioventricular rhythm (consider if less than or ~120 bpm)
- Metabolic
- Irregular
- Atrial fibrillation/atrial flutter with variable AV conduction AND bundle branch block^
- Atrial fibrillation/atrial flutter with variable AV conduction AND accessory pathway (e.g. WPW)
- Atrial fibrillation + hyperkalemia
- Polymorphic ventricular tachycardia
^Fixed or rate-related
ICD malfunction
Evaluation
- ECG or clinical history for those with ICDs
Management
Emergency Department
- Follow current ACLS guidelines if pulseless
- Analgesia / sedation for all patients
- ACC recommends repletion of K to 4.5 in all cases [4]
- Amiodarone 1st line antiarrhythmic (preferred over lidocaine) for most cases[5]
- Efficacy of lidocaine highest if actively ischemic
- Beta blockade: Minimize epinephrine use as much as possible
- Consider sympathetic blockade as first line over ACLS antiarrhythmics
- Especially in patients that are high risk CAD
- 67% vs. 5% survival in 49 patient study, respectively for esmolol/propranolol vs. ACLS antiarrhythmic[6]
- Patients who survived initial ES event did well over 1 yr follow up
- Metoprolol 2.5-5mg IV q2-5 min to max of 15mg
- Propranolol 0.15mg/kg IV over 10 minutes followed by 3-5mg q6h; may be effective even if metoprolol fails
- More efficacious than metoprolol, terminated VT at 3 hours vs. 18 hours with metoprolol [7]
- Esmolol 300-500 mcg/kg load over 1 minutes follwed by infusion at 25-50 mcg/kg/min initial dose
- Consider sympathetic blockade as first line over ACLS antiarrhythmics
- Exceptions to above are:
- Torsades with known long QT
- Magnesium sulfate 1-2 grams IV over 1-2 minutes
- Potassium repletion
- If bradycardic between episodes, pace at 90-120 or start Isoproterenol 2 mcg/min and titrate to HR 90-100
- Consider bolus dose 0.02-0.06mg isoproterenol, then infusion
- Brugada syndrome[8]
- Isoproterenol infusion is 1st line
- Quinidine may be of benefit[9]
- Due to its Ito channel blockade
- Sodium channel blockade may be harmful, however (avoid other Class I antiarrhythmics)
- Torsades with known long QT
- Consider isoproterenol in electrical storm in the following situations:
- Recalcitrant idiopathic ventricular fibrillation, not associated with structural heart, electrical, coronary heart disease
- Benign early repolarization with J waves[10]
- Idiopathic ventricular fibrillation with complete right bundle branch block
- Consider isoproterenol carefully as it has been used to induce ventricular tachycardia by EPs[11]
Inpatient
- Emergent revascularization if ischemic
- Ablation
- Left sympathetic ganglionic blockade
- Deep sedation / general anesthesia
- IABP / ECMO
- Palliative care as this could represent impending terminal failure
Disposition
- Admit
See Also
External Links
References
- ↑ Brigadeau F et al. Clinical predictors and prognostic significance of electrical storm in patients with implantable cardioverter defibrillators. Eur Heart J 2006;27:700-7.
- ↑ Credner SC, Klingenheben T, Mauss O, et al. Electrical storm in patients with transvenous implantable cardioverter-defibrillators: incidence, management and prognostic implications. J Am Coll Cardiol 1998; 32:1909
- ↑ Hohnloser SH, Al-Khalidi HR, Pratt CM, et al. Electrical storm in patients with an implantable defibrillator: incidence, features, and preventive therapy: insights from a randomized trial. Eur Heart J 2006; 27:3027
- ↑ Zipes DP et al. ACC/AHA/ESC 2006 Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death. J Am Coll Card 2006;48(5):e247-346.
- ↑ Eifling M, Ravazi M, Massumi A. The Evaluation and Management of Electrical Storm. Tex Heart Inst J 2011;38(2):111-21
- ↑ Nademanee K et al. Treating Electrical Storm: Sympathetic Blockade Versus Advanced Cardiac Life Support–Guided Therapy. Circulation. 2000; 102: 742-747.
- ↑ Chatzidou, S., Kontogiannis, C., Tsilimigras, D. I., Georgiopoulos, G., Kosmopoulos, M., Papadopoulou, E., … Rokas, S. (2018). Propranolol Versus Metoprolol for Treatment of Electrical Storm in Patients With Implantable Cardioverter-Defibrillator. Journal of the American College of Cardiology, 71(17), 1897–1906.
- ↑ Jongman JK et al. Electrical storms in Brugada syndrome successfully treated with isoproterenol infusion and quinidine orally. Neth Heart J. 2007 Apr; 15(4): 151–155.
- ↑ Belhassen B et al. Efficacy of Quinidine in High-Risk Patients With Brugada Syndrome. Circulation. 2004; 110: 1731-1737.
- ↑ Aizawa Y et al. Electrical storm in idiopathic ventricular fibrillation is associated with early repolarization. J of Am Coll of Card. Vol 62, No 11, 2013.
- ↑ de Meester A et al. Usefulness of isoproterenol in the induction of clinical sustained ventricular tachycardia during electrophysiological study. Acta Cardiol. 1997;52(1):67-74.