Rivaroxaban versus warfarin in postoperative atrial fibrillation: Cost-effectiveness analysis in a single-center, randomized, and prospective trial.

OBJECTIVES

Postoperative atrial fibrillation is the most common clinical complication after coronary artery bypass graft surgery. It is associated with a high risk of both stroke and death and increases the length of hospital stay and costs. This study aimed to evaluate anticoagulants in postoperative atrial fibrillation.

METHODS

A single-center, randomized, prospective, and open-label study. The trial was conducted in Heart Institute at University of São Paulo, Brazil. Patients who developed postoperative atrial fibrillation were randomized to anticoagulation with rivaroxaban or warfarin plus enoxaparin bridging. The primary objective was the cost-effectiveness evaluated by quality-adjusted life years, using the SF-6D questionnaire. The secondary end point was the combination of death, stroke, myocardial infarction, thromboembolic events, infections, bleeding, readmissions, and surgical reinterventions. The safety end point was any bleeding using the International Society on Thrombosis and Haemostasis score. Follow-up period was 30 days after hospital discharge.

RESULTS

We analyzed 324 patients and 53 patients were randomized. The median cost-effectiveness was $1423.20 in the warfarin group versus $586.80 in the rivaroxaban group ( = .002). The median cost was lower in the rivaroxaban group, $450.20 versus $947.30 ( < .001). The secondary outcome was similar in both groups, 44.4% in warfarin group versus 38.5% in the rivaroxaban group ( = .65). Bleeding occured in 25.9% in the warfarin group versus 11.5% in the rivaroxaban group ( = .18).

CONCLUSIONS

Rivaroxaban was more cost-effective when compared with warfarin associated with enoxaparin bridging in postoperative atrial fibrillation after isolated coronary artery bypass grafting.