At which age does heart failure occur for a person whom has an undetected asd and pfo?

Do not know: It could occur at many different ages depending on the person and the size of the asd. Perhaps a cardiologist can help us here with more information..

Increases with age: "heart failure" is defined as heart disease that creates an inability to meet the bodies demands for oxygen. In asd, there are multiple factors that can contribute to this. In isolated asd, this is extremely rare in the first ten years of life, but by age 40, in one degree or another, exists in the majority of patients with large asd. Pfo (and small asds) do not cause heart failure.

Depends: On the size of the defect. A pfo should never lead to heart failure. Similarly, a small ASD should never/rarely lead to heart failure. Medium and large asds can lead to hear failure, bu the time varies per person. Irreversible changes occur in lung arteries by ~8 years of age with large asds, but heart failure may not develop for years or even decades later.