Don't give up because you're in hospice. My father is 86 years old with a history of two MI's and a 5 way bypass. In early November he went into the hospital with an infection and had a third devastating heart attack. He survived with an EF% between 25% and 30% and was sent to a rehab center before going home to be given home care. He continued to decompensate and was changed to hospice care as it was the feeling of all involved that his time was limited. Everyday I expected to be his last then suddenly he got more energy back. The dementia started clearing and he began walking again, then fully taking care of himself and today we paid the bills together, went for a ride and a cup of coffee and we're ready to start talking about going back on home care so things happen.
About your condition, the dizziness is most likely due to low blood pressure which could be a result of the AFIB. My dad developed AFIB for the first time from the last MI. There are drugs available to boost your blood pressure, you should discuss that with your Doctor ASAP.