True statement about Ductus Aeriosus is :

Answer is D (May cause machinery murmur by its patency) Shunt murmur in patent ductus aeriosus is a continuous machinery murmur. Anatomic closure of Ductus aeriosus may take upto three months. Physiological closure (mediated by bradykinin) occurs almost immediately after bih by contraction of its muscular wall. Anatomic closure occurs by proliferation of intima, and may take from 1-3 monthsQ (& not in 24 hrs). Ductus aeriosus after obliteration forms ligamentum aeriosum.Q (& not the ligamentum venosum) - Closure of the ductus venosus forms the Ligamentum venosum. - Closure of distal pa of umbilical aeries --)forms medial umbilical ligament. Q - The proximal pa of umbilical aery remains patent as the "superior vesical aery". Q - Closure of umbilical vein -forms the ligamentum teres hepatis. Q Prostaglandins maintain patency of ductus aeriosus, and do not induce it to close "In neonates with congenital hea defects, till surgery is undeaken, PGE1 (Alprostadil) is used to maintain patency of ductus aeriosus".- Prostaglandins maintains patency of ductus aeriosus NSAIDs - help in early closure of ducts aeriosus Ductus aeriosus may cause a machinary murmur by its patency. "Shunt murmur is a continuous machinery murmur". The murmur is best heard at the 2nd left intercostal space and is also well heard below the left clavicle, where it maintains its continuous machinery character.