Combined Impact of Chronic Kidney Disease and Contrast Induced Acute Kidney Injury on Long-term Outcomes in Patients with Acute Lower Limb Ischaemia.

INTRODUCTION: Acute lower limb ischaemia (ALI) is the sudden onset of decreased arterial perfusion with imminent threat to limb viability. Contrast induced acute kidney injury (CI-AKI) is one of the complications that increases mortality in patients who undergo contrast imaging in coronary procedures. The goal of this study is to evaluate the impact of chronic kidney disease (CKD) and CI-AKI on long-term clinical outcomes in patients with ALI undergoing lower limb revascularisation.

METHODS: A total 1017 consecutive patients with acute lower limb ischaemia who were admitted between July 1, 2006, and January 1, 2017, were retrospectively reviewed. Patients who had end stage renal disease, those who had end stage heart and malignant disease and died within 7 days of limb revascularisation, and those who did not undergo angiography were excluded. Thus 546 patients were included in the final analysis. Patients were classified as with or without CKD and were then subdivided according to the presence or absence of the development of CI-AKI, defined as an increase in serum creatinine of ≥0.5 mg/dL or by ≥25% from the baseline value within the first 72 h after contrast exposure. The primary end point was all cause mortality and secondary major adverse limb event (MALE).

RESULTS: Both CKD and CI-AKI were associated with the highest rate of all cause mortality (chi square = 55.77, d.f. = 1, p < .01, log rank test) and MALE (chi square = 79.07, d.f. = 1, p < .01, log rank test). The presence of CKD and CI-AKI were significant risk factors associated with long-term all cause mortality (HR = 2.61, p < .01) and MALE (HR = 2.87, p < .01).

CONCLUSION: In patients with ALI undergoing lower limb revascularisation, both CKD and CI-AKI were significantly associated with poor long-term outcomes compared with either CKD or CI-AKI alone. Further studies are required to assess this association and to confirm the combined effect of CKD and CI-AKI on long-term clinical outcomes.