Hello,
The very small risk of a patent foramen ovale (PFO) (unless if it is large) occurs when there is a blood clot (or air bubble, or deoxygenated blood) traverses through the PFO from right atrium to the left atrium.
Normally the pressure in the left atrium is greater than the right atrium, hence there is no clinical risk.
However, when there is a reversal of left/right pressures, there is a small possibility that any blood clot or air bubbles or deoxygenated blood might traverse from right atrium to left atrium. When this occurs, it might cause some neurological or cardiac symptoms.
Situations or actions such as deep sea diving or straining with breath holding might transiently cause right atrial pressure to be greater than the left, resulting in this flow reversal of right to left atrial flow.
When an infant is traveling by airplane, the risk of a blood clot forming in the venous vessels is unlikely (unless there is a hereditary blood clotting problem), so the risk of blood clot flowing from right to left atria is almost non-existence.
Air bubble forming in the body system does not happen in air travel, although this may occur during deep sea diving which is not relevant for infants.
Lastly, even when if there is a small amount of deoxygenated blood flowing from right to left atria, it is of no consequence generally, unless the infant has an associated serious congenital heart or lung diseases.
Hence, there is no problem for an infant with PFO to travel by air. (unless there are associated underlying conditions that I have mentioned, such as hereditary blood clotting problems, or severe congenital heart or lung diseases).
Dr Chee Tek Siong
