Benthos
Contributor
Did you ever get a bubble echo for the PFO? A drysuit can be very effective at squeezing down all your peripheral vasculature. This increases the amount of blood that is returned to the heart which can increase the pressure in the right side of the heart. This then creates a pressure gradient for flow through a PFO to the left heart (allowing bubbles to bypass the lungs and be returned to the body.) Perhaps the only thing you did different was wear a drysuit? I'm not sure if any studies have been done to see if drysuits increase venus return to the right heart or not but the principle is the same as "the pneumatic anti shock garment" so I don't see why it wouldn't. On the other hand the test for the pfo is expensive, invasive and not without risk so thats something to consider too.