The impact of chronic kidney disease on outcomes following percutaneous coronary interventions versus coronary artery bypass grafting in patients with complex coronary artery disease: 5-year follow-up of the SYNTAX trial.

Aims: The aim of this study was to investigate short-term and five-year follow-up results from patients randomised to coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) with paclitaxel-eluting stents in the SYNTAX trial, focusing on patients with chronic kidney disease (CKD). Methods and results: Baseline glomerular filtration rate estimates (eGFR) were available in 1,638 patients (PCI=852 and CABG=786). The Kidney Disease: Improving Global Outcomes (KDIGO) threshold was used to define staging of CKD. At five years, death was significantly higher in patients with CKD compared to patients with normal kidney function after PCI (26.7% vs. 10.8%, p<0.001) and CABG (21.2% vs. 10.6%, p=0.005). Comparing PCI with CABG, there was a significant interaction according to kidney function for death (p(int)=0.017) but not the composite endpoint of death/stroke/MI (p(int)=0.070) or MACCE (p(int)=0.15). In patients with CKD, the rate of MACCE was significantly higher after PCI compared with CABG (42.1% vs. 31.5%, p=0.019), driven by repeat revascularisation (21.9% vs. 8.9%, p=0.004) and all-cause death (26.7% vs. 21.2%, p=0.14). In patients with CKD who also had diabetes, PCI versus CABG was significantly worse in terms of death/stroke/MI (47.9% vs. 24.4%, p=0.005) and all-cause death (40.9% vs. 17.7%, p=0.004). Conclusions: During a five-year follow-up, adverse event rates were comparable between PCI and CABG patients with moderate CKD but significantly higher compared to the patients with impaired or normal kidney function. The negative impact of CKD on long-term outcome following PCI appears to be stronger when compared to CABG, especially in the CKD patients with diabetes and extensive coronary disease.