My mother lived into her 90s, much earlier, my wife and I were called to the hospital, they felt she would soon pass away (she didn't) and we noticed she was wearing a DNR Wristlet (Do Not Resuscitate). I asked her if she knew what it meant, she did.

Despite the Wristlet, later that night, they gave her a Pacemaker. She instantly turned around, she was a different person. She had a Pacemaker with a Defibrillator, and it fired once when it shouldn't have. Apparently her afib had influenced the bottom of the heart so much that the Defibrillator thought it was needed. To prevent this, they Ablated the AV Node, there was then no way for the Atrial Fibrillation to influence the Ventricles. At that point she was Pacemaker Dependent.

She lived for 5 or more years after that, healthy as can be expected (she had other issues), and she passed away from something unrelated to the heart and pacemaker.

It was my understanding that for Afib that doesn't respond to medication, and ablation, that pacemakers are used and the AV Node is ablated, that way the ventricles no longer respond to the rapid chaotic rates of the Atrium. Ask your doctor about your AV Node, is in intact or has it been ablated. Rarely, there's another way Atrial Signals make it to the Ventricles, I believe they're called Accessory Pathways, they'd have to be ablated too, but they're not common.