Torsades de Pointes

SVT

Peri-arrest rhythms: tachycardia

The 2015 Resuscitation Council (UK) guidelines have simplified the advice given for the management of peri-arrest tachycardias. Separate algorithms for the management of broad-complex tachycardia, narrow complex tachycardia and atrial fibrillation have been replaced by one unified treatment algorithm

Following basic ABC assessment, patients are classified as being stable or unstable according to the presence of any adverse signs:

• shock: hypotension (systolic blood pressure < 90 mmHg), pallor, sweating, cold, clammy extremities, confusion or impaired consciousness
• syncope
• myocardial ischaemia
• heart failure

If any of the above adverse signs are present then synchronised DC shocks should be given. Up to 3 shocks can be given; after this expert help should be sought.

Treatment following this is given according to whether the QRS complex is narrow or broad and whether the rhythm is regular or irregular. The full treatment guidelines can be found at the Resuscitation Council website, below is a very limited summary:

Broad-complex tachycardia

Regular

• assume ventricular tachycardia (unless previously confirmed SVT with bundle branch block)
• loading dose of amiodarone followed by 24 hour infusion

Irregular

• seek expert help. Possibilities include:
  • atrial fibrillation with bundle branch block - the most likely cause in a stable patient
  • atrial fibrillation with ventricular pre-excitation
  • torsade de pointes

Broad-complex tachycardia. It can be difficult to distinguish between ventricular tachycardia and supraventricular tachycardia with aberrant conduction (e.g. LBBB). This patient did not respond to adenosine and was cardioverted. The final presumed diagnosis was that of ventricular tachycardia secondary to severe ischaemic heart disease. - e Image used on license from Dr Smith, University of Minnesota