Question

What problems would occur if a newborn’s foramen ovale failed to close?

Answer 1

Foramen ovale is the opening in the interatrial septum of the fetal heart which allows the flow of blood from right atrium to the left atrium bypassing the non functional lungs in fetus. Generally, foramen ovale closes after birth and gets converted into fossa ovalis of adult heart. In around 20%-25% of newborns, foramen ovale remains open (patent) called patent foreman ovale.

Generally, patent foramen ovale remains asymptomatic throughout the life but in rare cases it can cause paradoxical embolic stroke, hypoxemia, migraine with aura and decompression sickness in deep sea divers.

In few individuals with patent foramen ovale, if a blood clot develops in the venous system, it can get dislodged and travel from right side of the heart to the left side through patent foramen ovale. From the left side of the heart, this embolus gets pumped into the systemic circulation and might enter the brain causing stroke.

In some cases, significant amount of deoxygenated blood can pass from the right atrium to the left atrium bypassing the lungs through patent foramen ovale causing hypoxemia.

In individuals with patent foramen ovale, during deep sea diving decompression sickness can occur due to air blood clot with enters the systemic circulation through patent foramen ovale.