Prognostic Impact of Mildly Impaired Renal Function in Patients Undergoing Multivessel Coronary Revascularization

Abstract

Background: The long-term prognostic impact of mildly decreased renal function in patients undergoing coronary revascularization is still unknown.

Objectives: The goal of this study was to investigate the long-term prognostic impact of mildly decreased renal function and comparative outcomes after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) in such a risk group of patients.

Methods: From the Asan Medical Center-Multivessel Revascularization registry, 10,354 eligible patients who underwent coronary revascularization were classified into 3 groups (stage I [n = 3,735]: normal renal function; stage II [n = 5,122]: mild dysfunction; and stage III [n = 1,497]: moderate dysfunction) according to estimated glomerular filtration rate. The primary outcome was the composite of death, spontaneous myocardial infarction, or stroke. Propensity score matching was used to assemble a cohort of patients with similar baseline characteristics.

Results: After propensity matching, the risk for primary composite outcome was not different between the stage I and the stage II group (HR: 1.12; 95% CI: 0.97-1.30). However, the risk of the primary outcome was significantly higher in the stage III group than in the stage I group (HR: 1.50; 95% CI: 1.22-1.84). The relative effect of PCI vs CABG for the primary outcome was similar in the matched cohort of each renal function group of stages I, II, and III.

Conclusions: In patients with multivessel disease after revascularization by PCI or CABG, the presence of mildly decreased renal function was not significantly associated with an increased risk of the primary composite outcome and mortality. Comparative outcomes after PCI and CABG were similar in the borderline-risk group.