someone i know of developed AF after a near fatal episode of sepsis.
she had an echocardiogram and other tests, and saw a nurse specialist in haemophilia centre. they deal with more than that, but that's what it's called, somewhat alarmingly.
anyway the nurse there was very helpful and he explained that it would be wise for her to take rivaroxaban, so as to head off risk of stroke or heart attack.
she also takes something for high blood pressure, and many other medications as she has multiple morbidities and is mostly bed-bound.
she has been told to avoid stress, and when her family are lambasting her, as they often do, i've told her to say that medical advice is she must avoid stress, and just end the call.