Definition
- Heart rate > 100 beats per minute
- QRS duration > 0.12 sec (3 small squares )
If the patient is unstable, or you are feeling uncertain, do not over-complicate your management. Follow the management algorithm below. Call for expert help.
Differential Dx
- Ventricular tachycardia
- Monomorphic VT
- Polymorphic VT
- Torsade de Pointes
- Special cases e.g. idiopathic and RVOT
- SVT with with aberrancy
- SVT with pre-existing BBB
- Atrial or AV-nodal re-entry tachycardia with pre-excitation (rare)
- Much more commonly in EM, If QRS >200ms or rate is <120, think hyperkalaemia or drug (e.g. TCAD) overdose and consider Ca++ ± bicarb



Broad complex tachy. & instability
- Chest pain or SoB
- Poor peripheral perfusion
- SBP <90 mmHg
- Pulmonary congestion
- Altered consciousness
The following are adverse
- HR > 150 /min
- Polymorphic VT
- Irregular broad tachy. (?AF with alternative pathway)
- QRS >200ms (one big square) or rate <120 - think toxidrome (e.g. TCAD) or hyperkalaemia