Association of Preoperative Renal-Resistive Index With Long-term Renal and Cardiovascular Outcomes After Cardiac Surgery

Abstract

ObjectiveTo investigate the association of elevated preoperative renal resistive index (RRI) with persistent renal dysfunction, major adverse kidney events (MAKE) and major adverse cardiovascular events (MACE) after cardiac surgery. DesignObservational cohort study. SettingUniversity hospital. ParticipantsNinety-six adult patients undergoing cardiac surgery. InterventionsRRI measurement the day before surgery. Measurements and Main ResultsFifty-eight patients (60%) had elevated RRI ≥0.70. Five years after surgery, persistent renal dysfunction (sustained decline in estimated glomerular filtration rate ≥25%) had occurred in 25 patients (26%), MAKE (persistent renal dysfunction, renal replacement therapy, or death) in 34 (35%), and MACE (myocardial infarction, unstable angina, decompensated heart failure, stroke, or cardiovascular death) in 28 (29%). RRI was higher in patients who developed persistent renal dysfunction (median, 0.78 [interquartile range, 0.74-0.82] vs. 0.70 [0.66-0.77], p = 0.001), MAKE (0.77 [0.72-0.81] vs. 0.68 [0.65-0.76], p = 0.002), and MACE (0.77 [0.72-0.81] vs. 0.70 [0.66-0.77], p = 0.006). Patients with elevated RRI had a significantly higher cumulative incidence of all long-term outcomes. After adjustment for baseline renal function and heart failure, elevated RRI was associated with persistent renal dysfunction (hazard ratio [HR], 5.82 [95% confidence interval, 1.71-19.9]), MAKE (HR, 4.21 [1.59-11.1]), and MACE (HR, 2.81 [1.03-7.65]). ConclusionsElevated preoperative RRI is associated with persistent renal dysfunction, MAKE and MACE after cardiac surgery. Preoperative RRI may be used for long-term risk assessment in patients undergoing cardiac surgery.