During the fetal life, small portion of the RV output passes to the lung through the pulmonary artery, while the greater portion is shunted to the descending aorta through the fetal ductus arteriosus (1) which is a connection between the left pulmonary artery and descending thoracic aorta just distal to the left subclavian artery.
With transition from intrauterine to extrauterine life, physiological changes occur resulting in left to right reversal of the shunt through the ductus arteriosus. Increased oxygenation after birth results in calcium and potassium channel activity ending in ductus closure(2).
Patent ductus arteriosus (PDA ) is a congenital heart disease(CHD) represents 6-11% of all CHDs (3) and results from failure of closure of the ductus beyond the third month of age(4).
However, there are a subset of patients who survive to adulthood undiagnosed, and it is present in adulthood with various clinical presentations. The clinical presentation, hemodynamics, and management of PDA presentation in adults depend on various factors, primarily the size of PDA, magnitude of shunting, and status of pulmonary vasculature (5).