Fetal arrhythmias are not uncommon in pregnancy. The diagnosis can be established on routine ultrasound scan. Fetal supraventricular tachycardia (SVT) is the most common cause of fetal tachycardia. If left undiagnosed and untreated, these fetuses may develop cardiac failure, hydrops fetalis and eventually death. We report two fetuses diagnosed antenatally to have fetal SVT. Both fetuses were in cardiac failure and were successfully treated with maternal administration of antiarrhythmic medications. Digoxin, and in severe instances, a combination with flecanaide significantly improved fetal outcomes and prevented fetal mortality. The long term prognosis of such patients are good.