Ventricular dysrhythmias in pregnancy Amiodarone should be considered a last choice in pregnancy. It is the only class D antiarrhythmic, and even short infusions can be associated with fetal hypothyroidism, IUGR, fetal bradycardia, and prematurity. Lidocaine or procainamide are preferred. Also, cardioversion/defibrillation/pacing is considered safe in any stage of pregnancy.