Does Sodium Nitroprusside Decrease the Incidence of Atrial Fibrillation After Myocardial Revascularization?

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 microg x kg(-1) x 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.