The prognostic role of postoperative serum creatinine(within 24 hours)for in-hospital and one-year mortality in middle-aged and aged patients with rheumatic heart disease

Background Increased serum creatinine(SCr)was common after cardiac surgery and associated with poor outcomes.However,the prognostic role of postoperative SCr level measured on the morning of the first day was unclear in middle-aged and aged patients with rheumatic heart disease(RHD)undergoing valve replacement surgery(VRS).Methods Consecutive middle-aged and aged patients(age≥45 years)diagnosed with RHD undergoing at least one valve replacement were enrolled.Patients were routinely taken into the intensive care unit(ICU)for special care within 1 hour after VRS.SCr was measured at ICU admission and on the first day morning(within 24 hours).Association of postoperative SCr level with in-hospital and one-year mortality was analyzed.Results 3919 patients were finally included and divided into 4 groups according to the quartiles of postoperative SCr level on the first day morning:<1.0 mg/d L(n=1064),1.0-1.2 mg/d L(n=892),1.2-1.5 mg/d L(n=956)and≥1.5 mg/d L(n=1007).SCr level measured on the first day morning following surgery was an independent predictor for in-hospital mortality(adjusted OR:3.42,95%CI:2.52-4.63,P<0.001)and 1-year mortality(adjusted HR:2.99,95%CI:2.32-3.86,P<0.001).SCr level measured at this time had a greater predictive power for inhospital mortality than that measured at the time of ICU admission after surgery(P<0.001).Cumulative one-year mortality was significantly higher in patients with upper postoperative SCr quartiles on the first day morning(Logrank:125.75,P<0.001).Conclusions Postoperative SCr level measured on the first day morning could serve as an early and powerful prognostic marker for in-hospital and one-year mortality in middle-aged and aged RHD patients undergoing VRS.Attention should be paid to RHD patients with increased postoperative SCr level within24 hours after surgery.