V Tach Mimics
                                =============

þ Ventricular Tachycardia Mimics ("Slow V.Tach.") 
 - Ventricular tachycardia: ventricular rhythm with rate > 120 BPM 
 - Beware the diagnosis of VT in the patient with heart rate < 120 BPM!! 
   If HR< 120, consider 
  + Hyperkalemia 
  + Type lA medication toxicity TCA toxicity 
  + Cocaine toxicity Reperfusion arrhythmia 
    (accelerated idioventricular rhythm, AP AlVR) 
 - Treatment of these arrhythmias with traditional medications (lidocaine, amiodarone, 
   etc.) may induce asystole 
   [McLean, et al (Ann Emerg Med, 2000)]
    
I cases of WCT due to hyperkalemia misdiagnosed as VT 

Treatment with lidocaine induced asystole 
Hyperkalemia potentiates the sodium channel blocking effect of lidocaine 


Treatment of post-thrombolytic AIVR with lidocaine (and other 
antiarrhythmics?) may also induce asystole 


Safest treatment, when in doubt, is sodium bicarbonate or electncal cardioversion