Multiplane Transesophageal Echocardiography for Congenital Heart Disease

With the introduction of the first transverse mounted miniature single plane probes for pediatrics, it was immediately apparent that the evaluation of congenital defects also required a transducer aligned to provide longitudinal imaging ~1anes.l.~ A significant problem in pediatrics is that when biplane probes are created, the transverse and longitudinal scanning transducers are stacked one above the other on the transesophageal echocardiography (TEE) shaft. This is done to allow an equivalent and adequate number of elements to be grouped in each plane. In order to scan the same area of the heart with both transverse and longitudinal planes, however, a major repositioning of the probe is required. This is particularly disruptive during examination of the small hearts of young babies. This discontinuity in imaging hinders the comprehension of three-dimensional anatomy. Matrix construction probes, in which longitudinal and transverse mounted elements are interdigitated, have been developed, but are not commercially a~ailable.~ As the normal heart does not sit transversely and longitudinally aligned in the chest, “off axis” views obtained by leftor rightward lateral flexion of the entire articulated segment of the probe tip are required.6 The heart of the infant sits even more obliquely in the chest than in the adult. In the small esophagus of the child, very little lateral flexion is possible and the articulated segment of the probe is often 5-6 cm above the actual transducer reducing further the angulation achievable. Deep transgastric imaging techniques have been developed that allow longitudinal imaging of both left and right ventricular outflow track7 Although being equivalent to subcostal imaging, the outflow tracts are displayed only in the far field of the transducer, and therefore,