Echocardiographic evaluation of the ductal morphology in patients with refractoriness to lipo-prostaglandin E-1 therapy

Background: Lipo-prostaglandin (PG)E-1 is effective at lower doses and has fewer side effects than PGE(1)-cyclodextrin (CD). Previous studies, however , have suggested that some patients show refractoriness to lipo-PGE(1) in t he course of treatment. The present paper examines: (i) whether such cases can be predicted by examining the ductal morphology before and 24 h after t he start of lipo-PGE(1) infusion; and (ii) whether PGE(1)-CD dilates the du ctus arteriosus in patients with refractoriness to lipo-PGE(1). Methods: The ductal morphology was evaluated with two echo indices, such as minimal and minimal plus maximal intraluminal diameters of the ductus. Two -dimensional echocardiography was performed in 24 patients with ductus-depe ndent congenital heart disease. The two echo indices were measured before a nd 24 h after lipo-PGE(1) infusion and also at least twice per week until s urgery. Results: In 19 of 24 patients, ductal patency was maintained until surgical treatment (group A). The remaining five patients (21%) showed ductal closu re during the course of the lipo-PGE(1) therapy (group B). There were no si gnificant differences between the two groups, in either the maximal or mini mal diameters, which were examined before and 24 h after treatment. In the five patients of group B, lipo-PGE(1) was replaced with a relatively high d osage of PGE(1)-CD (50-100 ng/kg per min), resulting in good ductal patency until surgery. Conclusions: Patients with refractoriness to lipo-PGE(1) therapy could not be predicted from initial intraluminal diameters of the ductus using echoca rdiography. Therefore, serial echocardiographic examinations are important to detect early findings of ductal closure. In addition, PGE(1)-CD is still useful as back-up therapy in such patients.