Applications of intravascular scanning and transesophageal echocardiography in congenital heart disease: tradeoffs and the merging of technologies.

This chapter will review the evolving role of intravascular ultrasound imaging and transesophageal echo in the care of children, infants and adults with congenital heart disease. The technologies relevant to congenital heart disease applications differ from those involving coronary disease since the intravascular structures imaged often involve visualization of large vessels and cardiac chambers. On the other hand, the requirements for transesophageal echo in children with congenital heart disease involve intraoperative (surgical) and imaging procedures in the catheterization laboratory which are performed for monitoring interventional catheterization therapy. As such, whereas the intravascular devices needed for pediatric cases involve lower frequency and sometimes larger catheters, the requirements for transesophageal echocardiography require higher frequency and smaller esophagoscopes. Applications of intravascular imaging including sizing of congenital stenoses, dilation of coarctation and valvular stenoses, imaging of intrapulmonary thrombi and monitoring of placement of ASD 'button' devices in the heart will be reviewed. The intraoperative transesophageal uses for monitoring infant surgery include procedures for tetralogy repair, transposition repair and repair of AV septal defects and other complex congenital heart disorders. Both of these 'invasive' methods of echocardiography have an important and evolving role in the management of congenital heart disease in children and infants.