Miniaturized transesophageal echocardiography in newborn infants

Background and Methods: A miniaturized 5.5 to 10 MHz, phased-array, single longitudinal plane transducer mounted on a 3.3-mm diameter catheter (miniaturized transesophageal echocardiography [TEE]) may overcome mechanical limitations of standard pediatric transesophageal probes. We evaluated whether the miniaturized TEE probe could define clinically relevant anatomy in 17 infants who weighed less than 6 kg. Results: Twenty-two studies were performed in 17 infants without complication, weighing 2.1 to 5.6 kg. Twenty of twenty-two studies were diagnostic. Pediatric biplane TEE was not possible in 13 studies. Lack of horizontal plane imaging with miniaturized TEE made evaluation difficult in patients with atrioventricular septal defect. Conclusion: Miniaturized TEE provided diagnostic intraoperative TEE in the majority of infants studied and may allow broader and safer application of TEE to neonates and small infants.