Post CABG AF is usually self-limiting and therapy with amio should only be kept on for a couple of months maximum. There are other medications with less side effects that can be tried if the AF persists. You are correct that the risk of complications is related to the dose and the duration of exposure. Other than pulmonary fibrosis which is very rare, complications, such as liver problems or tyroid problems, are much more frequent and shoud be sought after with blood work testing.
Many thanks to the MD who answered my question. Very helpful!