Skip to Main Content

++

Introduction

++

Interventions developed during the past three decades have dramatically altered the course of selected fetal anomalies and conditions. Reviewed in this chapter are fetal disorders amenable to treatment with either maternal medication or surgical procedures. The treatment of fetal anemia and thrombocytopenia is reviewed in Chapter 15, and the treatment of some fetal infections is discussed in Chapters 64 and 65.

++

Medical Therapy

++

Fetal pharmacotherapy, administered to the mother and transported transplacentally, can be used to treat an array of serious conditions. Two well-described examples are fetal tachyarrhythmia treatment with medications such as digoxin, and corticosteroid therapy to prevent virilization of female fetuses with congenital adrenal hyperplasia. More recently, a course of corticosteroid therapy—the same used to promote lung maturity before preterm birth—has been used to stabilize the growth of large fetal lung masses and avoid fetal surgery.

++
Arrhythmias
++

Fetal cardiac rhythm disturbances may be broadly categorized as tachyarrhythmias, heart rates > 180 beats per minute (bpm); bradyarrhythmia, heart rate < 110 bpm; and ectopy, typically premature atrial contractions. Fetal M-mode sonography (Bradyarrhythmia) should be performed to determine the atrial and ventricular rate to clarify the relationship between atrial and ventricular beats, thereby diagnosing the rhythm disturbance type.

++
Premature Atrial Contractions
++

This is by far the most common arrhythmia. Premature atrial contractions are identified in 1 to 2 percent of pregnancies and are generally a benign finding (Hahurij, 2011; Strasburger, 2010). They represent immaturity of the cardiac conduction system and typically resolve either with advancing gestation or in the neonatal period. Although they may be conducted, they are more commonly blocked, and with handheld Doppler or fetoscope, they sound like a dropped beat. Premature atrial contractions are not associated with major structural cardiac abnormalities, but they sometimes occur with an atrial septal aneurysm. As shown in Figure 10-24 (M-Mode), M-mode evaluation demonstrates that the dropped beat is a compensatory pause following the premature atrial contraction. They may occur as frequently as every other beat, known as blocked atrial bigeminy. This results in an auscultated fetal ventricular rate as low as 60 to 80 beats per minute. Unlike other causes of bradycardia, this carries a benign prognosis and does not require treatment (Strasburger, 2010).

++

Approximately 2 percent of fetuses with premature atrial contractions are later identified to develop supraventricular tachycardia (SVT) and require urgent treatment to prevent development of hydrops (Copel, 2000; Srinivasan, 2008). Given the importance of identifying such tachycardia, the fetus with premature atrial contractions is often monitored with heart rate assessment every 1 to 2 weeks until ectopy resolution.

++
Tachyarrhythmias
++

The two most common are supraventricular tachycardia and atrial flutter. SVT is characterized by an abrupt increase in the fetal heart rate to 180 to 300 bpm with 1:1 atrioventricular concordance. The typical range is 200 to 240 ...

Want remote access to your institution's subscription?

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.

Ok

About MyAccess

If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.