My mom suffered a massive stroke where she was left without use of 1/2 of her body (she was paralized on one side of her body), she was unable to speak, unable to care for herself AT ALL. She lived this way for 3 1/2 years, receiving 24-hour care from her family and independently-paid nurses the majority of time (she was in two sub-standard nursing homes for a bit before we pulled her out).
Anyway, I was with her when she suffered a massive heart attack. She seized up and moved BOTH of her arms up toward her chest area. This is particularly noteworthy, because she moved one of her arms that was paralyzed, and which she'd been unable to move for 3 1/2 years.
I knew she was dying, but we (my wonderful sisters and I) had made a calculated decision that, if mom's health deterioted in any way, we would NOT do anything to assist her situation. No EMT, no ambulance, no nothing. She did not die immediately, but did linger on for a few days until she did pass. During this time, we did relent and had her transferred to the hospice unit at the hospital, but we withheld medication and food from her. She passed after three days.
After caring for her for 3.5 years, and being a witness to her general unhappiness at her physical limitations, I can say that it was a great blessing when she died.
I am so glad that I did not call 911 when she suffered her last heart attack.