Complications

A small patent ductus arteriosus might not cause complications. Larger, untreated defects could cause:

• High blood pressure in the lungs. Too much blood circulating through the heart's main arteries through a patent ductus arteriosus can lead to pulmonary hypertension, which can cause permanent lung damage. A large patent ductus arteriosus can lead to Eisenmenger syndrome, an irreversible type of pulmonary hypertension.
• Heart failure. A patent ductus arteriosus can eventually cause the heart to enlarge and weaken, leading to heart failure, a chronic condition in which the heart can't pump effectively.
• Heart infection (endocarditis). People who have structural heart problems, such as a patent ductus arteriosus, are at a higher risk of an inflammation of the heart's inner lining than are people who have healthy hearts.