Regarding the injury and death, the reports just don't add up.
- There was a lot of blood -- the window looks clean.
- There was a heart attack.
- The victim of the heart attack died.
- The passenger who got sucked out died of her injuries.
- It has also been proposed that the fuselage got pierced in a position different from the window, so the injury and blood would have been elsewhere.
All in all, this could be one person or three who had this happen to them.
Someone who has lost blood due to traumatic injury may suffer a cardiac arrest - or enter a state called PEA (pulseless electrically activity).
In the absence of a pulse, trained first aiders would likely start CPR and, if available, attach an AED (automated external defibrillator). Depending on the nature of the arrest the AED will decide whether or not to administer a shock.
All this activity would lead many bystanders to describe what they are witnessing as a "heart attack".