Improved Renal Function After Percutaneous Coronary Intervention in Non-Dialysis Patients With Acute Coronary Syndrome and Advanced Renal Dysfunction

Background: The deterioration of renal function is a strong prognostic predictor in patients with coronary artery disease. Although percutaneous coronary intervention (PCI) has sometimes resulted in improved renal function (IRF) in acute coronary syndrome (ACS) patients, its clinical implications have not been fully elucidated. This study aimed to investigate the prevalence and predictors of IRF after PCI and its relationship with long-term renal outcomes. Methods: In this retrospective observational cohort study, we examined data from 177 ACS patients with non-dialysis advanced renal dysfunction (estimated glomerular filtration rate [eGFR] < 30 mL/min/1.73 m²) who underwent PCI. Patients with and without IRF were compared in terms of baseline demographic, clinical, and procedural characteristics and renal outcomes. IRF was defined as a 20% increase in eGFR from baseline at 7 or 30 days after the index PCI. Results: IRF was observed in 66 (37.3%) patients. ST-elevation myocardial infarction and shock during PCI were independent predictors of IRF. Patients were followed up for a median of 695 days. Kaplan-Meier analyses demonstrated that patients with IRF had the lower incidence of initiation of permanent dialysis than those without IRF (Log-rank P = 0.015). Conclusions: IRF was relatively common in non-dialysis patients with ACS and advanced renal dysfunction who underwent PCI. ST-elevation myocardial infarction and shock, which may be indicative of hemodynamic instability during PCI, were independent predictors of IRF. Further, IRF was associated with favorable renal outcomes. Hemodynamic stabilization may be important for improving the short-term and long-term renal outcomes of high-risk patients.