Serum uric acid as a simple risk factor in patients with rheumatic heart disease undergoing valve replacement surgery

Background: We evaluated the relationship between admission serum uric acid (SUA) and in-hospital and oneyear mortality after valve replacement surgery (VRS) for patients with rheumatic heart disease (RHD). Methods: One-thousand five-hundred thirty-six consecutive patients with RHD undergoing VRS were divided into 4 groups based on the quartiles of SUA on admission. The association between SUA and adverse outcomes was analyzed. Results: The in-hospital mortality (2.1% vs 2.6% vs 5.3% vs 7.7%, p < 0.001) and postoperative acute kidney injury (AKI) (52.0% vs 52.6% vs 61.6% vs 63.3%, p = 0.001) increased from the lowest to the highest SUA quartiles. SUA levels were negatively correlated with eGFR value (r = 0.426, p < 0.001) and positively correlated with C-reactive protein value (r = 0.103, p < 0.001). ROC analysis showed that SUA had good predictive value for in-hospital death (AUC = 0.665, p < 0,001) and was similar to Euro score (Z = 0.966, p = 0.334). Multiple logistic regression analysis showed that SUA was independently associated with in-hospital (OR = 1.21, 95% CI: 1.06, 1.37, p = 0.004) and one-year mortality (HR = 1.17, 95% CI: 1.05, 1.29, p = 0.003). Kaplan Meier analysis demonstrated that the cumulative rate of one-year mortality after surgery was higher in patients with SUA > 7.3 mg/dl (Log-rank = 21.1, p < 0.001). Conclusions: Admission SUA could be used as a preoperative risk assessment factor in RHD patients who underwent VRS.