Arrhythmias are the most common cardiac complication encountered during pregnancy in women with and without structural heart disease [1-3]. Arrhythmias may manifest for the first time during pregnancy or pregnancy can trigger exacerbations in women with known pre-existing arrhythmias [1,4-6].
The prevalence, clinical presentation and management of ventricular arrhythmias will be reviewed. Cardiac arrest during pregnancy, general management of ventricular arrhythmias and cardiac arrest, electrocardiographic characteristics of ventricular arrhythmias, and issues relating to supraventricular arrhythmias during pregnancy are discussed in detail elsewhere. (See "Cardiopulmonary arrest in pregnancy" and "Approach to the diagnosis and treatment of wide QRS complex tachycardias" and "Advanced cardiac life support (ACLS) in adults" and "ECG tutorial: Ventricular arrhythmias" and "Supraventricular arrhythmias during pregnancy".)
Women with established arrhythmias or structural heart disease are at highest risk of developing arrhythmias during pregnancy. Due to surgical advances, the number of women of childbearing age with congenital heart disease has increased and this group of women is at particularly high risk for arrhythmias (figure 1) [1,2,7-11]. (See "Pregnancy in women with congenital heart disease: General principles".) Since arrhythmias are frequently associated with acquired or structural heart disease, any woman who presents with an arrhythmia during pregnancy should undergo clinical evaluation for structural heart disease (including an electrocardiogram and a transthoracic echocardiogram). (See 'VT in women with structural heart disease' below.)
In general, the approach to the treatment of arrhythmias in pregnancy is similar to that in the non-pregnant patient. However, due to the theoretical or known adverse effects of antiarrhythmic drugs on the fetus, antiarrhythmic drugs are generally reserved for the treatment of arrhythmias associated with significant symptoms or hemodynamic compromise [12-14]. Treatment strategies during pregnancy are hampered by the lack of randomized trials in this cohort of women. Choice of therapy, for the most part, is based on limited data from animal studies, case reports, observational studies, and clinical experience.
MECHANISM OF ARRHYTHMOGENESIS IN PREGNANCY
The exact mechanism of increased arrhythmia burden during pregnancy is unclear but has been attributed to hemodynamic, hormonal, and autonomic changes related to pregnancy.