Patent Foramen Ovale (PFO)

The Patent Foramen Ovale is a channel a couple of inches wide, which is normally present in everyone whilst we are still in the womb.

At birth, the entrance to the channel is covered by a membrane which is reinforced in early childhood, and does not allow blood (or bubbles) to pass through.

Often (30-40% of people), at birth or in later life, the membrane face can lift, and move  blood (and blood clots or bubbles) that are on the right side of the heart to the left side (right-left shunt).

The Ravenna Hyperbaric Centre has a unique approach to  the process of diffusion, because it uses a procedure that identifies potential "holes" that may be helping blood to transfer  from the right to the left side of the circulatory system (heart, lung, other).

For this reason, the course of treatment proposed by the Ravenna Hyperbaric Centre includes following visits  and tests.

Step 1

Investigations to check for a predisposition to produce thrombi and emboli

  • Complete blood cell and platelet counts, haptoglobin, total protidemia, serum iron, serum creatinine, glucose, ALT, AST, urinalysis, total cholesterol, HDL cholesterol, triglycerides, uric acid, ESR, CRP, fibrinogen, ANA, anti-ENA, C3, C4, protein S, antithrombin III, activated protein C resistance, homocysteine, CEA, GICA, Ca 19-9, hepatitis markers, rheumatoid factor, FT4, TSH, PT, PTT and INR
  • genetic test for the detection of genes related to factor V Leiden, factor II coagulation (prothrombin) and the MTHFR gene (methylenetetrahydrofolate reductase).
  • capillaroscopy (to exclude abnormalities correlated to a rheumatic disease)
  • thyroid ultrasound (to rule out thyroid disease, possibly autoimmune)
  • tests for occult blood in the stools (do not eat meat during the week preceding the examination; preferably repeating the test three times, at a spacing of one month between one examination and the others).



Blood gas analysis and ultrasound

  • sampling of arterial blood (blood gas) whilst breathing in pure oxygen at a high flow rate (normal value> 400 mm Hg)
  • testing the head, with an ultrasound, for the possible passage through a "shortcut" of small, harmless bubbles injected into the arm via a drip (transcranial Doppler ultrasound with sonographic contrast; normal value <20 bubbles as a total of the counts on both sides of the skull) .


Step 3

Ultrasound (if Step 1 is positive)

  • test, again using ultrasound, for a "hole" in the heart (patent foramen ovale, searching via trans esophageal electrocardiography (examination performed at the Ravenna Cardiology Hospital). It is important to assess whether the extent of the shunt is compatible with the values ​​recorded in Step 1


Step 4

Radiological investigation

  • Step 4 is activated when the result of Step 2 is not consistent with the values ​​recorded in Step 1: only in such cases is a radiological procedure (pulmonary angiography) required to exclude the presence of other "holes" in the lung or elsewhere (extra cardiac right/ left shunt).

The Ravenna Hyperbaric Centre offers a test package for assessing the presence and severity of the right / left shunt.

All examinations (transcranial Doppler ultrasound, oxygen test, diving medical assessment by Dr. Pasquale Longobardi) are carried out at the Centre in a single day (Tuesday).

For information, contact the Secretary (+39 0544-500152).