[Value of the subxiphoid approach in 2-dimensional echocardiography for the diagnosis of ductus arteriosus in premature infants and infants].

The preliminary results of our experience with the "inverted" subxiphoid approach for 2D echocardiographic visualisation of patent ductus arteriosus (PDA) in premature neonates and infants are reported. Eight premature ventilated neonates weighting 870 to 1,200 g with an isolated PDA were examined by this technique using a mechanical sector scanner and a 7.5 MHz transducer; three views were obtained (left ventricular outflow tract or "long axis"; an oblique view through the two atria and aortic arch; short axis view of the ventricles). A PDA was directly visualised in 6 of the 8 patients. It was possible to measure its diameter and observe its tortuous or rectilinear trajectory; the outcome of Indomethacin therapy or surgical ligature could also be evaluated. In the 2 patients in whom the PDA was not visualised, there were no clinical symptoms or echocardiographic signs of shunt: these PDA were therefore probably extremely small. In the neonate and infant, it is relatively easy to demonstrate a PDA by this approach. The PDA can also be followed up in "ductus dependent" congenital heart disease during treatment with Prostaglandin E. In conclusion, the subxiphoid approach represents an interesting alternative for the visualisation of PDA, especially in premature neonates in whom the suprasternal and parasternal views are often difficult to obtain.