Recent Strategies and Outcomes of Transcatheter Closure for Patent Ductus Arteriosus

Patent ductus arteriosus (PDA) is a congenital heart disease defined as the arterial connection between the pulmonary artery and the aorta. The ductus arteriosus is an essential structure that shunts blood away from the lungs during fetal life, and only becomes abnormal if it remains patent more than three months after birth in term infants. Spontaneous delayed closure of the ductus arteriosus occurred in 79% of infants during the neonatal period. The overall incidence in infants born prematurely is about 16 times higher than the incidence in full term infants. The rate of PDA in extremely premature neonates is close to 30%. Preterm infants with symptomatic heart failure secondary to persistent patency of the ductus arteriosus may be treated by surgical ligation or medically with conservative treatment such as indomethacin or ibuprofen. Medical intervention is usually the treatment of choice due to the risks involved with surgical ligation. Early surgical ligation was supported as the optimal therapy for PDA because it ensured definitive ductal closure with minimal morbidity and mortality in theses high risk infants. Diagnosis of PDA is usually based on clinical examination and transthoracic echocardiography. Now that color Doppler imaging has been introduced, it is possible to accurately assess even a tiny PDA. PDAs are usually classified as small, moderate or large by size measurement, and as type A (conical ductus), B (window like ductus), C (tubular ductus), D (ductus with multiple narrowing) or E (elongated ductus) by its configuration on an angiogram of the aortic arch. The traditional approach of PDA closure, either with surgery or, more recently, with transcatheter techniques, has been the mainstay of treatment. And management of PDA has continued to progress as innovative technologies have become available. Thus, the outcome and goals for PDA closure have changed and depend on the treatment modality. Indeed, strategies for management of PDA continue to evolve.