Fetal Arrythmias. Before and after Birth. A Leeds Experience from 2000-2012

Objective: To review the management of fetal arrhythmias during pregnancy and follow these fetuses in later life to monitor final outcome.

Method: Retrospective review on a database of 139 pregnant women and follow up of their babies in cases here details were available. Arrhythmias were grouped together based on their type. Antenatal management of arrhythmias and progress of babies into later childhood was documented.

Results: Patients were subclassified into heart blocks (n27, live birth n17), atrial flutter (n7, live birth n6), supraventricular tachycardia (SVT) ( n38, live birth n15), ectopics (30), arrhythmia with abnormal heart structure (17), and others (18). No antenatal treatment was used to improve heart rate in bradyarrhythmia and postnatal treatment was an artificial pace maker in majority of live births at some stage of childhood. In tachyarrhythmias the rate was controlled with digoxin or flecanide and amiodarone was used in refractory cases. A tachyarrhythmia may resolve spontaneously after birth but may need a combination of anti arrhythmics to control rate. If a baby has an SVT in neonatal period than he is more likely to require radio frequency ablation later in life as compared to the one`s who do not have SVT in neonatal period. These babies can be symptom free and come off anti arrhythmics in early years of life.

Conclusion: In case of a live birth with heart block, majority of babies will need a pacemaker at some stage of their life with good quality of life provided that they do not have complications of pacemaker insertion. Tachyarrhythmias can be managed with antiarrhythmic therapy in utero and have a favorable outcome later on in life provided the rate can be controlled in utero.