Fetal Dual Doppler Echocardiography

Abstract

Dual Doppler echocardiography is a recently developed technique performed using an instrument with two separate sample gates, allowing simultaneous recording of signals from two locations. We describe the use of dual Doppler echo cardiography to assess fetal cardiac rhythm. Fetal arrhythmias are common and encountered in 1 to 2% pregnancies. They often resolve spontaneously and do not require treatment, but sometimes lead to severe morbidity and mortality. Fetal arrhythmias are responsive to fetal therapy and require appro priate management through accurate diagnosis. Pulsed wave Doppler and Mmode echocardiography are widely used to assess fetal cardiac rhythm. Both methods have advantages and limitations, which are influenced by fetal position, image resolution, and the complexity of the arrhythmia. We developed a new technique that records pulsed wave Doppler signals in the hepatic vein (HV) and the descending aorta (DAo) simultaneously using dual Doppler. This method is less influenced by fetal position and the complexity of the arrhythmia, and the images have better resolution than those acquired using conventional Doppler methods in most cases. Although, electrical parameters, such as the QT interval cannot be evaluated, dual Doppler recording of flows in HV and DAo is an efficient and effective method for assessing fetal cardiac rhythms, allowing precise diagnosis of cardiac arrhythmias.