AF after cardiac surgery leads to excess mortality and morbidity. Colchicine was used in several studies to lower the incidence AF but the results were generally disappointing. There was no benefit in reducing AF and there was a high incidence of GI side effects especially diarrhea, often leading to stopping the medication. However, a recently published meta-analysis showed that colchicine reduced AF, but again warned of the high incidence of GI side effects. The maintenance dose of colchicine used in these studies was 1 mg daily it is hypothesized that low dose colchicine (0.5 not 1 mg colchicine) might lower AF after cardiac surgery without the prohibitive GI side effects Patients will be randomized to colchicine vs. placebo started the day before surgery and continued until hospital discharge.
The primary efficacy endpoint will be the incidence of AF. The primary safety endpoint will be the GI side effects
