Divers should consider screening for Patent Foramen Ovale (PFO)
What is PFO?
PFO is a small opening between the upper chambers of the heart (atria) that normally closes shortly after birth. However, in some individuals, it remains open, allowing blood to flow between the atria.
Why is PFO relevant to divers?
For divers, PFO poses a risk due to the changes in pressure during dives. When a diver ascends, the pressure changes can cause nitrogen bubbles to form in the bloodstream (decompression sickness). If a PFO is present, these bubbles can bypass the lungs’ filtering mechanism and travel directly to the brain, heart, or other organs, potentially causing:
- Decompression sickness (DCS)
- Arterial gas embolism (AGE)
- Stroke
Who should consider screening?
Routine screening for PFO in divers without symptoms are not indicated. However the following patients may be considered for screening:
- Recurrent or severe DCS or AGE
- Unexplained neurological symptoms (e.g., stroke, seizures, or migraines)
- Family history of PFO, atrial septal defects or stroke
- Other heart conditions (e.g., atrial septal defects)
Screening methods
Screening typically involves:
- Transesophageal echocardiography (TEE)
- Transthoracic echocardiography (TTE)
- Contrast echocardiography (bubble study)
- Transcranial Doppler with bubbles
What if I have PFO?
If you’re diagnosed with PFO, your doctor may recommend:
- Closure of the PFO (percutaneous or surgical)
- Modified diving practices (e.g., shallower dives, slower ascents)
- Avoiding technical diving or high-risk diving activities
Consult a cardiologist or a diving medicine specialist to discuss your individual risk factors and determine if screening is necessary.