What if PDA doesn't close?

What Happens If a PDA Doesn’t Close?

When a patent ductus arteriosus (PDA) remains open beyond the newborn period, the consequences can be serious if left untreated. This small blood vessel, which should naturally close shortly after birth, connects the aorta and pulmonary artery. When it stays open, it creates abnormal blood flow between these two major vessels, placing extra strain on the heart and lungs.

One of the primary concerns is ventricular hypertrophy, where the heart’s left ventricle thickens from working overtime to pump excess blood. Over time, this can lead to congestive heart failure, especially in infants and young children. Another long-term risk is pulmonary vascular disease, where increased blood flow to the lungs damages the pulmonary arteries. In severe cases, this may progress to Eisenmenger syndrome, a condition where the direction of blood flow reverses due to high lung pressures, causing oxygen-poor blood to circulate through the body.

Children with untreated PDA may also experience poor physical growth, as their bodies struggle to meet increased metabolic demands. They’re at higher risk for infective endocarditis (IE), a dangerous infection of the heart lining or valves, often triggered by everyday bacteria. Additionally, the persistent blood flow through the ductus can lead to structural changes like aneurysmal dilatation or even ductal calcification, making future closure more complex.

While small PDAs may cause minimal symptoms, larger ones demand timely medical or surgical intervention. Early detection and treatment—through medication, catheter-based procedures, or surgery—can prevent these complications and allow for normal heart function and development. Ignoring a PDA may seem harmless at first, but the long-term toll on the cardiovascular system underscores the importance of proactive care.