Absent pulmonary valve is a rare defect in which the pulmonary valve is either missing or poorly formed. The pulmonary valve allows oxygen-poor blood to travel from the heart to the lungs. When the pulmonary valve is missing, the branch pulmonary arteries are very enlarged and press down on the airways in the lung, causing breathing problems.
Update Date 2/17/2014
Updated by: Kurt R. Schumacher, MD, Pediatric Cardiology, University of Michigan Congenital Heart Center, Ann Arbor, MI. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.