even patients without a definable electrophysiologic substrate for sustained vt or vf remained at risk for arrhythmia recurrence if treated with alternative antiarrhythmic medications : 40 % of such patients who continued to receive an antiarrhythmic agent different from that being administered when their clinical vt or vf occurred had recurrent spontaneous ventricular tachyarrhythmias during follow-up .
C0003811
arrhythmia
C0042510
vf