What causes Eisenmenger syndrome?

What causes Eisenmenger syndrome?

Uncorrected structural defects in the heart cause Eisenmenger syndrome. Most people with this condition were born with a ventricular septal defect (hole between the two lower chambers of their heart). This hole allows more blood to flow into the lungs than is normal, causing pulmonary hypertension (increased pressure in the lung’s arteries).

After time, pulmonary hypertension damages the blood vessels in the lungs. This damage causes the blood flow to reverse direction and go back out to the body without receiving oxygen in the lungs. In order to avoid serious complications, patients may have to limit exercise and strenuous activities.

Besides ventricular septal defect, other congenital heart problems that can cause Eisenmenger syndrome include:

• Atrial and atrioventricular septal defect – a combined hole in the upper two chambers of the heart
• Patent ductus arteriosus – failure of the passage between the pulmonary artery (blood vessel leading to the lungs) and the aorta (the body’s main artery) to close after a baby is born
• Truncus arteriosus – only one blood vessel leads out of the heart instead of the normal two