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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
- Amiodarone
- 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.