From the Guidelines
A patent ductus arteriosus (PDA) can close spontaneously, particularly in full-term infants, with approximately 50-60% experiencing spontaneous closure by 1 year of age. The ductus arteriosus is a vascular connection between the aorta and pulmonary artery that is present in fetal life, and it typically closes shortly after birth 1. However, in some individuals, it remains patent, with a prevalence of about 0.3% to 0.8% in term infants, and is twice as common in females as males 1.
Spontaneous Closure
The likelihood of spontaneous closure decreases with lower gestational age, and in premature infants, spontaneous closure occurs less frequently. The biological mechanism behind closure involves the vessel responding to increased oxygen tension after birth, which triggers contraction of smooth muscle in the ductal wall, followed by anatomical remodeling and permanent closure.
Clinical Implications
For those whose ductus remains patent in adulthood, catheter-based or surgical intervention consideration depends on the symptoms and physiological expression of the lesion 1. Follow-up of these patients as adults is important for all, although timing and testing will vary among individuals. Many PDAs are now closed in infancy or childhood with catheter-based or surgical approaches, and the clinical and physiological manifestations of the PDA are dependent on the size of the vessel and the relative systemic and pulmonary vascular resistances 1.
Management
If a PDA doesn't close spontaneously, medical interventions such as NSAIDs (indomethacin or ibuprofen) may be used to promote closure, or in persistent cases, surgical or catheter-based closure may be necessary. The 2018 AHA/ACC guideline for the management of adults with congenital heart disease provides recommendations on who should perform surgeries, cardiac catheterization, and other procedures in these patients, as well as diagnostic evaluation and follow-up intervals 1.
From the Research
Spontaneous Closure of Patent Ductus Arteriosus
- The ductus arteriosus can undergo spontaneous closure in some premature infants, as mentioned in the study by 2.
- According to the study by 3, spontaneous closure of the PDA has been reported in up to 40-67% of very low birth weight (VLBW) infants by 7 days.
- The study by 4 also suggests that patency of the ductus arteriosus may be a physiological manifestation of extreme prematurity and may not necessarily need to be therapeutically closed.
Factors Influencing Spontaneous Closure
- The incidence of patent ductus arteriosus (PDA) is inversely proportional to the gestational age, as stated in the study by 3.
- The study by 5 found that in many preterm low-birth-weight infants, the ductus arteriosus fails to close spontaneously.
- The use of cyclo-oxygenase inhibitors such as indomethacin and ibuprofen can promote closure of the PDA, but spontaneous closure can still occur in some cases, as mentioned in the study by 2.
Management of Patent Ductus Arteriosus
- The management of PDA in premature infants is a subject of controversy, with different approaches including prophylactic treatment, therapeutic treatment, and conservative management, as discussed in the study by 4.
- The study by 6 reviews the treatment options for PDA, including pharmacological treatment with indomethacin or ibuprofen, and surgical ligation.
- The study by 3 proposes a more rational approach to the management of PDA, including a trial of conservative management during the first week, followed by selective use of anti-inflammatory drugs.