Acute treatment and prevention of ventricular tachycardia
THE CONTEXT
Ventricular tachycardia (VT) requires prompt restoration of sinus rhythm, usually followed by preventive therapy. Acute treatment depends on haemodynamic tolerance.
Acute treatment
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Synchronised DC cardioversion is the treatment of choice when systolic blood pressure is below 90 mmHg or the arrhythmia is poorly tolerated.
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For well-tolerated VT, intravenous amiodarone may be given as a bolus followed by continuous infusion.
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Intravenous lidocaine is another option, but may depress left ventricular function and cause hypotension or acute heart failure.
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Correct hypokalaemia, hypomagnesaemia, acidosis and hypoxia when present.
Drug prevention
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β-blockers prevent VT by reducing ventricular automaticity. Amiodarone can be added when further control is needed.
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Class Ic anti-arrhythmic drugs should not be used for VT prevention in coronary artery disease or heart failure because they depress myocardial function and may increase dangerous arrhythmias.
Devices and catheter ablation
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An implantable cardiac defibrillator is recommended when left ventricular function is poor or VT is associated with haemodynamic compromise.
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Catheter ablation can interrupt the focus or circuit in resistant focal or scar-mediated VT.
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Catheter ablation is the treatment of choice for VT in a normal heart and can often be curative.