Successful catheter fulguration of the His bundle in a postoperative Mustard patient after unsuccessful fulguration of ectopic atrial foci.

Incessant supraventricular tachycardia (SVT) resistant to pharmacological agents may cause cardiac dysfunction requiring more aggressive therapy. We present the case of a 12-year-old postoperative Mustard patient who developed biventricular heart failure due to an atrial ectopic tachycardia resistant to amiodarone. Using endocavitary direct current fulguration techniques, catheter ablation of the His bundle was successfully performed after unsuccessful attempts at ablation of the ectopic atrial foci. After placement of a permanent transvenous rate responsive ventricular pacemaker, the patient's clinical status and cardiac function improved. Endocavitary fulguration of the His bundle is technically feasible after the Mustard procedure and should be considered for treatment of selective cases of pharmacologically resistant SVT.