I'll add my recent data point. I had what is being called Pulmonary Edema in Key Largo, diving on the wreck Duane. It now looks like I have occasional Atrial Fibrillation. I've never before noticed it, but it got measured for a few hours while I was on heart monitoring electronics in the hospital, starting about 1-1/2 days after the dive. Even though the nurses told me my heart was not operating properly, I felt normal. It looks like at depth, not enough blood was flowing into my brain. My breathing felt normal, and in fact the dive computer logging shows a pretty constant rate of air consumption the entire dive.
Over a period of time during the dive, I became aware of a loss of things feeling "right" or "normal" and a then a definite loss of coordination. I was going through a doorway and my gear bumped into the opening 3 times. My immediate thoughts were, "This is serious, I should normally just zip through that opening". There was probably some blurring of vision, as I found it difficult to read my computer. I'm not sure of this as it is a new computer to me with much smaller text than my old one (Oceanic VT3 vs US Divers Scan 4)
It was near the end of the dive time anyway, so I sort of abruptly signaled my buddy to go up. As it was on a wreck, there was an ascent line. I went up at a normal rate on the ascent line behind a crowd of other divers. About that time, I remember thinking that the people ahead of me are not going fast enough, I need to get to the surface sooner. The next day, my buddy told me that I let go of the ascent line and made a controlled swim to the surface.
On the surface, I was observed with my mask on my forehead (typical for me) but unconscious. I was hauled onto the dive boat and given oxygen. I have no memory from letting go of the ascent line until 25 minutes later receiving oxygen.
I was diving at around 102ft on EAN32. Max depth was 105ft. and total dive duration was 22 minutes. According to the profile stored on my dive computer, I didn't come near to any limits except PO2 was about 1.40 at that depth. I was wearing a borrowed shorty wet suit. I have 50 years experience scuba diving, having taken my first class and started in 1961 on a "J" valve, dual hose regulator, and no BCD. I am 67 years old.
Medically, I have hypertension and take medication. I also have thickened heart muscle in left ventricle. That morning, I took my usual Atenolol, Benicar, and Simvastatin (for hypertension and cholesterol control) PLUS a sudafed and Bonine.
