Three-dimensional imaging of the fetal heart: Current applications and future directions

During the past 25 years fetal echocardiography has evolved from a research tool to a clinical tool used by obstetricians, maternal–fetal medicine specialists, radiologists, and pediatric cardiologists. Each group of physicians faces different tasks. The non-pediatric cardiologist is primarily involved with screening for heart defects in low-risk patients while the pediatric cardiologist is charged with the delineation of complex fetal heart defects. Both tasks can be challenging. With the introduction of 3D and 4D fetal echocardiography, a number of modalities are available to assist the non-cardiologist when performing the screening examination of the fetal heart that includes evaluation of the four-chamber and the outflow tract views of the fetal heart. These include the “spin” technique and the evaluation of tomographic imaging planes. Using similar techniques the pediatric cardiologist can render 3D and 4D views of the heart that are equivalent to anatomical models of the heart, as well as examine 2D image planes derived from 3D and 4D datasets that assist in identifying the nine image planes that have been defined for fetal echocardiography.