Does sodium nitroprusside decrease the incidence of atrial fibrillation after myocardial revascularization? A pilot study

Background - Atrial fibrillation ( AF) often occurs after coronary artery bypass grafting and can result in increased morbidity and mortality. In the present pilot study, our aim was to investigate whether sodium nitroprusside (SNP), as a nitric oxide donor, can reduce the frequency of post - coronary artery bypass grafting AF. Methods and Results - To investigate the effectiveness of SNP in the prophylaxis of AF, we conducted a prospective, randomized, placebo-controlled clinical study on 100 consecutive patients in whom we performed elective and initial CABG operations. A control group of 50 patients were treated with placebo ( dextrose 5% in water), whereas the SNP group ( n = 50 patients) was treated with SNP ( 0.5 mu g center dot kg(-1) center dot min(-1)) during the rewarming period. High-sensitivity C-reactive protein levels were measured before surgery and 5 days postoperatively. All patients were monitored postoperatively with telemetry. Baseline characteristics were similar in both treatment groups. AF occurred in 12% of the SNP group and 27% of the control group. The occurrence of AF was significantly lower in the SNP group (P = 0.005). The duration of AF in the SNP group was significantly shorter than that in the control group (5.33 +/- 1.86 and 7.55 +/- 1.94 hours, respectively; P = 0.023). C-reactive protein levels were higher postoperatively in the control group than in the SNP group ( P < 0.05). Postoperative AF significantly prolonged postoperative hospital stay ( P < 0.05). Conclusions - The incidence of postoperative AF in the SNP group was reduced significantly. Further studies are needed to better delineate the anti-AF profile of SNP.