Treatment of arrhythmias during pregnancy.

During pregnancy, significant changes occur in the hormonal and hemodynamic state of women that make arrhythmias more likely to occur. Palpitations are frequently reported, but are usually found to be associated with sinus tachycardia. The incidence of paroxysmal supraventricular tachycardia is increased during pregnancy, whereas atrial fibrillation and ventricular tachycardia are rarely seen. Women with long QT syndrome experience significantly more cardiac events in the postpartum period, making beta-blocker therapy most important during this time. Acute treatment of arrhythmias for pregnant women is much the same as that for nonpregnant patients. However, chronic drug therapy during pregnancy should be reserved for only the frequent, hemodynamically significant arrhythmia episodes.