What happens if PDA is not treated?

What Happens If a Patent Ductus Arteriosus (PDA) Goes Untreated?

When a baby is born, a small blood vessel called the ductus arteriosus — which was essential during fetal development — usually closes on its own within the first few days of life. But when it remains open, it’s known as a patent duct. In some cases, especially with very small PDAs, the condition might cause no noticeable symptoms and may not require immediate treatment.

However, if a larger PDA is left untreated, it can lead to serious health issues over time. The main concern is the abnormal flow of blood between the heart and lungs, caused by the persistent connection between the aorta and the pulmonary artery. This extra volume of blood circulating into the lungs can lead to increased pressure — a condition known as pulmonary hypertension.

Pulmonary hypertension is not something to ignore. Over time, the added strain on the lungs and the heart’s left side can weaken the heart muscle and increase the risk of heart failure. Children with untreated large PDAs may also experience frequent respiratory infections, poor growth, and fatigue during physical activity.

Additionally, an unrepaired PDA can raise the long-term risk of endocarditis — an infection of the inner lining of the heart — especially if there’s persistent turbulent blood flow through the abnormal vessel. That’s why early diagnosis and monitoring are so important, even if symptoms seem mild at first.

While some small PDAs may close on their own or remain harmless, larger ones typically require medical or surgical intervention to prevent complications. The good news is that treatment options — including medications, catheter-based procedures, or surgery — are highly effective when timed appropriately. Regular follow-ups with a cardiologist ensure that any changes are caught early, helping to protect heart and lung health well into adulthood.