Statistical analysis of interim data showed no advantage of colchicine

The prior End-AF study by the same group showed that 1 mg of colchicine didn't decrease the incidence of AF after cardiac surgery. The current study, End-AF Low Dose Study, will test 0.5 mg colchicine vs. placebo in preventing AF after cardiac surgery.

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

Inclusion Criteria:

• All patients aged 18 years or above undergoing elective cardiac surgery.
• Sinus rhythm and no previous AF
• Agreed to sign informed consent.

Exclusion Criteria:

• Known severe liver disease or current transaminases >1.5 times the upper normal limit
• Current serum creatinine >2.5 mg/dL
• Known myopathy or elevated baseline preoperative creatine kinase
• Known blood dyscrasias or significant gastrointestinal disease
• Pregnant and lactating women
• Known hypersensitivity to colchicine
• Current treatment with colchicine for any indications
• Emergency surgery

Our Group's website will share data. Researchgate will share data. Eventual results will be announced to medical community through local presentations, and international congresses and publications.