Objective: To predict the effect of nesiritide on clinical outcomes based on the renal function change demonstrated in the Nesiritide Administered Peri-Anesthesia (NAPA) in patients undergoing cardiac surgery trial. Methods: We built a decision analytical model to replicate the NAPA trial with 1000 hypothetical patients in both nesiritide and placebo arms. The incident rates of dialysis, hospital death, and their composite were predicted based on the renal function data obtained from the NAPA trial. All analyses were further repeated for two subgroups stratified by the presence of preoperative renal dysfunction (RD). Results: The base-case analyses significantly favored nesiritide for the three clinical end points. In the total NAPA sample, the absolute risk reductions (ARRs) for dialysis, hospital death, and their composite across 100 simulated trials were 1.3%, 3.3%, and 4.1%, respectively. The improvement was more pronounced in the preoperative RD subgroup with the three ARRs of 4.1%, 7.1%, and 9.4%, respectively. The beneficial effect diminished in the normal preoperative renal function (NRF) subgroup with the three ARRs of 0.6%, 3.0%, and 3.4%, respectively. The best case analyses confirmed the robustness of the base-case results in the total NAPA sample and RD subgroup, but not in the NRF subgroup. Conclusion: If the demonstrated renal preservation can be extrapolated, nesiritide may reduce dialysis and hospital death in cardiac surgery patient with preoperative RD, but to a much lesser extent or not in patients with normal preoperative renal function. [ABSTRACT FROM AUTHOR]