Acute Kidney Injury After Mechanical Thrombectomy for Stroke in Patients With Pre-Existing Renal Impairment

Acute kidney injury (AKI) is a common but often underrecognized complication in ischemic stroke patients undergoing mechanical thrombectomy, particularly among those with pre-existing renal impairment. This study evaluated the incidence, risk factors, and clinical impact of AKI in this high-risk population.

This retrospective, two-center study involved 310 patients who underwent MT for ischemic stroke and presented with impaired renal function at baseline (eGFR < 60 mL/min/1.73 m²). AKI was defined according to the Kidney Disease: Improving Global Outcomes (KDIGO) criteria and categorized as post-contrast AKI (PC-AKI), which occurred within 48 h following contrast administration, and late-onset AKI (L-AKI), which developed later during hospitalization. We analyzed the clinical and laboratory factors that might predispose patients to the development of AKI and compared the clinical profiles of those with PC-AKI and L-AKI.

Acute kidney injury occurred in 91 patients, including 49 with PC-AKI and 42 with L-AKI. Patients who developed AKI were more likely to have pre-existing chronic kidney disease, prior NSAIDs use, and higher serum glucose and potassium levels at admission. Additionally, AKI was associated with longer hospitalization, increased in-hospital and 3-month mortality, and less favorable clinical outcomes overall. The independent predictors of AKI included NIHSS > 15 (OR: 3.441), WBC count (OR: 1.128), female sex (OR: 0.311), and the comorbidity burden (OR: 2.414).

Acute kidney injury represents a frequent and clinically relevant complication following MT in patients with pre-existing renal impairment. Early recognition and the implementation of preventive strategies are essential, particularly in patients with established risk factors for AKI.