Adenosine sensitive ventricular tachycardia occurs in structurally normal hearts and arises from the right ventricular outflow tract (pulmonary infundibulum). This gives it a left bundle branch block morphology on the 12-lead ECG.

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Adenosine can terminate this rhythm as the name implies, however ablation is the treatment of choice and success rates are high. Beta-blocker therapy is moderately effective to treat this rhythm. Unlike other forms of ventricular tachycardia, adenosine sensitive ventricular tachycardia is usually hemodynamically stable.

Verapamil sensitive ventricular tachycardia is a form of idiopathic ventricular tachycardia that occurs with a structurally normal heart arising from the left posterior fascicle. This manifests as a right bundle branch block pattern on the ECG with a left axis deviation. Verapamil can acutely terminate the rhythm as the name implies. Ablation is the therapy of choice.