"The<unk> or PDA, is a remnant of the distal sixth aortic arch and connects the pulmonary artery at the junction of the main pulmonary artery and the origin of the left pulmonary artery to the proximal descending aorta just after the origin of the left subclavian artery.<unk> (PDA) is a congenital heart defect when a child's<unk><unk>  fails to close after birth, producing a heart murmur described in 1898 by Gibson as the classic machinery murmur." from Wikidoc article:Patent<unk><unk>
Patent ductus arteriosus 
Persistent truncus arteriosus
Atrioventricular septal defect
Atrioventricular canal defect
Ductus arteriosus aneurysm
Tricuspid atresia
Atrial septal defect sinus venosus
Atrial septal defect