Eisenmenger Syndrome and Pulmonary Hypertension

Eisenmenger syndrome, a type of congenital heart defect, causes severe pulmonary hypertension. It most commonly results from a large hole in the heart between the two lower heart chambers (ventricles), called a ventricular septal defect (VSD), or a hole in the upper chambers (atria) of the heart called an atrial septal defect (ASD).

This "hole in the heart" forces blood to circulate abnormally in your heart. Oxygen-carrying blood (red blood) mixes with oxygen-poor blood (blue blood). The blood then returns to your lungs instead of going to the rest of your body, increasing the pressure in the pulmonary arteries and causing pulmonary hypertension.