Of course! And that's often the case with diving accidents. So many of them are ruled heart attacks.
I'm not speaking about this accident, but in general, there are lots of heart attacks for a variety of reasons. First, lots of divers are out of shape. If you exert yourself at depth, or if you dive a poorly serviced regulator, you'll build up CO2. If you're stressed, you'll also build up CO2. The body's response to CO2 in the brain is to raise your blood pressure.
The end result is your heart is working harder and this may lead to a heart attack.
So, quite often deaths get ruled as heart attacks, and that isn't very useful information for divers.
Instead, it helps to look at factors that contributed to the death.
Was the diver obese? Out of shape?
Was the diver trim and streamlined in the water or was he working much harder than he should have been?
Was the diver wearing too much lead (over-weighted)?
Was the diver experienced enough for the dive or would he have been stressed?
Was the diver's equipment well fitting and serviced?
All those things are factors that contribute to increased CO2 and ultimately to heart attacks underwater, and IMO it's much more useful to look at these contributing factors, ie the factors that actually led up to the cause of death, rather than look at the exact cause of death.
