The two men were on board a Hobie Wave sailboat that capsized and both men were thrown into the water.  Due to a cardia arrhythmia, one died and fell overboard.  With the weight not being on board, it may have been enough for the wind to capsize the boat, causing the operator to fall off; or,  the boat may have capsized, causing both men to fall overboard.  While in the water the passenger may have had cardiac arrhythmia and died.
Putnam                        