Wide QRS tachycardia refractory to pharmacologic interventions and cardioversion.

The case of a 43-year-old man with an idiopathic wide QRS tachycardia resistant to adenosine, lidocaine, procainamide, and multiple electric shocks is described. The tachycardia eventually stopped after a pacing wire was introduced in the right ventricle, inducing a run of rapid ventricular tachycardia. The possible causes of resistance to medications and cardioversion, and alternative treatment modalities are reviewed.