It was pretty surreal. I was sleeping when the incident started and they asked for medical personnel.
I woke up and there were a bunch of people standing in the aisle. I wasn't sure at first what was going on as I had missed the call for medical personnel. I could then tell they were working on someone in an aisle seat or the floor. There wasn't a lot of panic. I noticed across the middle set of seats in the other aisle was another flight attendant with a pen and paper writing down I'm assuming everything she saw happening.
The shock paddles then were brought up the aisle. It seemed right after that I heard someone ask for blankets. When they asked for blankets, I figured this was not that serious and the guy was just sick and not feeling well and they were going to make him feel better by warming him up.
Next thing I know, wrapped in the blankets, they carry the guy down the aisle to the back of the plane (I was sitting in the 3rd row from the back). I was perplexed why they didn't take the poor guy to first class to help him recover. I hadn't seen the guy but assumed it was a man for some reason.
Maybe 10 or 15 minutes later, a big American guy from the back comes up and starts talking to the guy in front of me. He says something along the lines of how he didn't expect that on the flight, and how "there wasn't anything they could do", the guy "never had a chance", something about "blockage" and they just delayed declaring him officially dead for a long time. Now that he was declared dead they said we would just keep flying straight to Dallas (this was a Seoul-Dallas direct flight and when this happened we were roughly half-way in and over the Pacific).
For the next 5 or 6 hours things went along as normal. There was a blanket left covering the aisle next to the guy's seat. The people sitting in the two seats next to him stayed in their seats.
The man had no family on the plane which made it even more surreal because there wasn't any grieving. We just kept flying as the guy was lying in the back galley of the plane with the curtains closed.
About 25 minutes before we landed they started clearing out the 2 rows of the plane behind me. Not a lot of communication as to what was going on. Then the brought out the body wrapped in blankets and strapped him in the last row for the landing. They had to secure him in case of a rough landing. His feet wrapped in the blankets stuck out into the aisle.
Also at this point, the flight attendants went to his row and started gathering his bag underneath his seat. They asked the two people seated next to him if they knew if he had an overhead bag.
We landed, they said something because of a medical situation, we would be going to a different terminal. When we pulled up there was a fire truck nearby and medical/police in the terminal.
I bet 2/3 of the plane didn't know what happened.
In the customs line, a lady on the flight who was trying to help the man with medical attention said he died of a blood clot. When they tried to do chest compressions blood just shot out everywhere (thus the blanket left on the floor) so there wasn't much that could be done. She said he was an elderly gentleman.
The situation was pretty bizarre. I guess people must die on planes quite a bit. It was strange we just kept on flying but there was nothing else we could do.
I googled, Deep vein thrombosis, to see if a clot could just kill you on the plane, but will leave that one for the doctors.