Tuesday August 25, 2009
Adenosine for wide-complex tachycardia: Efficacy and safety


Objectives: To determine whether adenosine is useful and safe as a diagnostic and therapeutic agent for patients with undifferentiated wide QRS complex tachycardia. The etiology of sustained monomorphic wide QRS complex tachycardia is often uncertain acutely.


Design: A retrospective observational study with emergency visits at nine urban hospitals. Consecutive patients treated with adenosine for regular wide QRS complex tachycardia between 1991 and 2006.

A positive response: was defined as an observed change in rhythm including temporary atrioventricular conduction block or tachycardia termination.

A primary adverse event: was defined as emergent electrical or medical therapy instituted in response to an adverse adenosine effect.

A rhythm diagnosis was made in each case. The characteristics of adenosine administration as a test for a supraventricular as opposed to ventricular tachycardia were determined, and the adverse event rates were calculated.


Results:

• A total of 197 patients were included: 104 (90%) of 116 and two (2%) of 81 supraventricular tachycardia and ventricular tachycardia patients demonstrated a response to adenosine, respectively.
• The odds of supraventricular tachycardia increased by a factor of 36 after a positive response to adenosine.
• The odds of ventricular tachycardia increased by a factor of 9 when there was no response to adenosine.
• The rate of primary adverse events for patients with supraventricular tachycardia and ventricular tachycardia was 0 (0%) of 116 and 0 (0%) of 81 respectively.
  
  

Conclusions: Adenosine is useful and safe as a diagnostic and therapeutic agent for patients with regular wide QRS complex tachycardia.



Reference:

Adenosine for wide-complex tachycardia: Efficacy and safety- Critical Care Medicine: September 2009 - Volume 37 - Issue 9 - pp 2512-2518