Milrinone Re-Dilates the Ductus Arteriosus in Patients with Ductus Arteriosus-Dependent Congenital Heart Diseases

Abstract

Treatment of patent ductus arteriosus is crucial for the survival of patients with ductus arteriosus (DA)-dependent congenital heart diseases. Prostaglandin E₁ (PGE₁) agents are commonly used to keep the DA open; however, maintaining an appropriately sized DA is difficult. We saw a patient with hypoplastic left heart syndrome (HLHS) and critical pulmonary stenosis (cPS) whose DAs had become narrow and were re-dilated by milrinone. The patient with HLHS had bilateral pulmonary artery banding and was awaiting the Norwood procedure. The diameter of the DA instantly decreased from 6.4 mm to 3.0 mm at 18 days of age during the administration of lipo-PGE₁. Although the administration of CD-PGE₁ was begun instead of lipo-PGE₁, the DA remained narrow. Therefore, we initiated the administration of milrinone at a dosage of up to 0.2 µg/kg/min. The DA quickly re-dilated to a sufficient size and remained open until the Norwood procedure. The patient with cPS was scheduled for percutaneous transluminal pulmonary valvuloplasty (PTPV). The diameter of the DA decreased from 3.7 mm to 1.2 mm at 3 days of age. The agent used was changed from lipo-PGE₁ to CD-PGE₁, but the DA remained narrow. As a result, we began administering milrinone and gradually increased the dosage to 0.4 µg/kg/min. The DA dilated after the initiation of milrinone treatment and remained open until the scheduled PTPV date. A narrow DA is a critical problem for patients with DA-dependent congenital heart disease, and additional treatments are required to avoid DA closure. Milrinone is another option besides PGE₁ agents to re-dilate the DA.