tokens: In the postoperative patient with tetralogy of Fallot with symptomatic ventricular arrhythmias , it is concluded that electrophysiologic study is useful in reproducing clinical episodes of VT and in selecting effective antiarrhythmic medication ; a small number of patients with ventricular premature complexes alone will have inducible sustained VT during electrophysiologic study ; prognosis of these patients may be improved by treatment that results in prevention of VT induction ; and in patients with right ventricular hypertension , VT is likely to be refractory to drug treatment .