Importance of ECGs, Management of Unstable Patients, and Sedation in Ventricular Tachycardia

Show Notes

Background/Overview of VT:

• Definition: What makes it a storm 
  • Three or more sustained episodes of VF, VT, or appropriate ICD shocks in a 24-hour period
• Pathophysiology: Understanding the origin and mechanism
  • Sympathetic drive/adrenergic surge
  • Underlying pathology: Sodium channelopathies, infiltrative disease like cardiac sarcoidosis, etc.
• RF’s / trigger / population (reversible cause in ~25% of patients)
  • MI
  • Electrolyte Derangements (emphasis on potassium and magnesium)
  • New/worsening heart failure
  • Catecholamine Surge
  • Drugs (stimulants, cocaine, amphetamines, etc)
  • QT Prolongation
  • Thyrotoxicosis

Clinical Presentation:

• Symptoms of VT: spectrum of symptoms – from palpitations to syncope to cardiac arrest
• Differentiating VT from other potential ER presentations.

Diagnostics in ER:

• Electrocardiogram (ECG): Recognizing VT patterns.
  • Monomorphic vs polymorphic (Torsades) may change management
  • Wide QRS
  • Fusion best
  • Capture beats
  • Concordance 
  • AV-dissociation
• Lab tests: Potassium, magnesium, troponins, TFTs, etc.

Acute Management in the ER:

• Hemodynamically stable vs. unstable V
  • Unstable = cardioversion
  • Sedation
    • Catecholamine surge should be considered 
    • No ideal agent 
    • Etomidate or propofol can be considered 
    • Ketamine may worsen irritability 
• Pharmacological treatments:
  • Amiodarone
    • Class III antiarrhythmic 
    • Most studied in VT storm 
    • First line
  • Beta Blockers
    • Propranolol
    • B1 and B2 activity 
• Non-pharmacological approaches:
  • Immediate synchronized cardioversion
  • IABP / ECMO considered for HD unstable patient
  • Cath lab if ischemic etiology suspected 
  • Stellate Ganglion Block

Take Home Points

• Definition: VT Storm is commonly defined as three or more sustained episodes of ventricular fibrillation, ventricular tachycardia, or appropriate ICD shocks within a 24-hour period.
• Varied Presentation: Patients may experience a range of symptoms from palpitations to severe hemodynamic instability.
• ECG and Diagnosis: Initial ECG may not show VT; continuous cardiac monitoring or device interrogation may be required for diagnosis.
• VT Identification: Look for wide QRS, rate over 100, fusion beats, capture beats, and AV dissociation to identify VT.
• Management in Hemodynamic Instability: Cardiovert if the patient shows signs of hemodynamic instability.
• Sedation Considerations: Be cautious with sedation, especially with ketamine, as it may worsen cardiac irritability in these already adrenergic state patients.
• Medication Choices: Typically, amiodarone and propranolol are used to manage VT Storm.
• Cardiology Involvement: Involve cardiology early on, as treatment may extend beyond medications.