By P. Syamasundar Rao, MD
Ductus arteriosus is a vascular structure that connects the main pulmonary artery with the descending thoracic aorta. In the fetus, the ductus arteriosus diverts deoxygenated blood from the pulmonary artery into the descending aorta and from there to the placenta for oxygenation.1,2 It closes spontaneously at birth,1,2 and is considered patent if it persists beyond 72 hours of life.3 The incidence of Patent Ductus Arteriosus (PDA) is 0.05% in full-term infants,4,5 and constitutes 10% of all Congenital Heart Defects (CHD). The incidence of PDA is high in preterm babies; the earlier the gestational age, the higher the incidence.3-6 The ductus remains open in 90% of babies born at 24 weeks gestation, in 80% of babies born between 25 to 28 weeks gestation and in 10% of infants born between 30 and 37 weeks gestation.6 The patency rates are also related to birth weight; 80% in babies weighing less than 1,200g and 40% in infants weighing less than 2,000g have PDAs.4 The adverse effects of PDA in preterm babies have been addressed in previous reviews.4,5,7,8 The clinical, roentgenographic and biomarker profiles are helpful in evaluating the significance of PDA in the premature; however, echocardiography appears to be the prime modality for detection and quantification of PDA in preterm infants. The purpose of this paper is to review the role of Echo-Doppler studies in the assessment of PDA in the premature infants.
To read the full article, please go to the April 2018 Issue of CCT, where it was originally published.