Cardiac arrhythmias during pregnancy.

Arrhythmias of the pregnant patient are rare. In most cases, the therapeutic agent chosen should be much the same as that in the nonpregnant patient, and an understanding of the pharmacology of the antiarrhythmic agents is necessary for rational use in the pregnant patient with an arrhythmia. Substantial experience has been accumulated using some of the older agents for treatment of arrhythmias in pregnancy. As newer agents become available, there may be indications for their use in pregnancy; however, we recommend initially using well-known drugs until more experience is gained with the newer ones. The choice of an agent should be made only after thorough evaluation of the patient's symptoms, accurate diagnosis and an analysis of potential benefit versus potential risk to the mother or fetus.