The drug colchicine reduced the incidence of post-pericardiotomy syndrome and post-surgery atrial fibrillation by nearly half in a placebo-controlled, randomized study.

Colchicine, often used to treat gout, greatly reduced the incidence of atrial fibrillation after heart surgery, according to late-breaking research presented at the American Heart Association's Scientific Sessions 2011. The Italian study is also published in Circulation: Journal of the American Heart Association.

"This is the first time that colchicine has been shown to prevent atrial fibrillation," said Massimo Imazio, M.D., lead author of the study and a cardiologist at Maria Vittoria Hospital in Turin, Italy. "The findings are clinically significant and provide evidence that colchicine may represent a cheap, safe option for the prevention of the post-pericardiotomy syndrome and post-operative AF."

AF is the most frequent complication after heart procedures such as coronary artery bypass grafting, valve surgery or combined bypass/valve surgery. It may affect more than 50 percent of patients after cardiac surgery. Post-pericardiotomy syndrome is a potential cause of the condition, and colchicine may reduce incidence of this syndrome as well as postoperative AF by half, Imazio said.

The study included 336 heart surgery patients from six centers in northern Italy. Their average age was 66 and 69 percent were men.

Study participants received either colchicine or placebo, beginning three days after heart surgery and continuing for one month. Neither patients nor investigators knew who received active drug or placebo.

One month after heart surgery, colchicine had cut the incidence of AF nearly in half - 12 percent of those taking colchicine had AF compared to 22 percent of patients given a placebo.

Furthermore, colchicine patients were hospitalized three fewer days - 21 versus 24 - than those who received a placebo.

Side effects were minimal and similar between the two groups. But colchicine patients were slightly more likely to experience gastrointestinal intolerance, the most common side effect.

The study had a relatively small sample size and scientists started the medicine three days post-surgery. So, before changing recommendations, future large-scale studies should initiate colchicine treatment earlier, ideally before surgery, since postoperative AF often occurs in the early days after surgical intervention.

"In that way, you might also be able to prevent atrial fibrillation in the first few days after the cardiac operation," Imazio said.

Colchicine is a plant-derived substance from the drug class of alkaloids, which also includes morphine and caffeine. It is not currently approved in North America or Europe for pericarditis, post-pericardiotomy syndrome or for atrial fibrillation prevention.

Co-authors are Antonio Brucato, M.D.; Paolo Ferrazzi, M.D.; Maria Elena Rovere, M.D.; Anna Gandino, M.D.; Roberto Cemin, M.D.; Stefania Ferrua, M.D.; Riccardo Belli, M.D.; Silvia Maestroni, M.D.; Caterina Simon, M.D.; Edoardo Zingarelli, M.D.; Alberto Barosi, M.D.; Fabrizio Sansone, M.D.; Davide Patrini, M.D.; Ettore Vitali, M.D.; Rita Trinchero, M.D.; David H. Spodick, M.D.; and Yehuda Adler, M.D.

The Maria Vittoria Hospital, ASLTO2, in Torino, Italy, funded the study for the Italian National Healthcare System.