Can svt trigger episodes of delirium in dementia patients? will svt/arrhythmia and dementia/alzheimer worsen each other over time?

A cardiac arrhythmia, whether rapid or very slow rate, can worsen confusion and I think could cause delirium in dementia cases. I don't believe that increasing dementia necessarily brings on more episodes of arrhythmia but the recurrent arrhythmias can worsen dementia by their effect on cerebral circulation and the brain injuries that could ensue.

Primary cardiac events can often result in secondary neurological symptoms which can be transient unless a stroke ensues as a complication. This doesn't cause Alzheimer's, but if dementia is already present, brain infarctions can cause vascular dementia, and the combined co-morbidities cause dramatic cognitive deterioration.