The Extent of Aortic Atherosclerosis Predicts the Occurrence, Severity, and Recovery of Acute Kidney Injury After Transcatheter Aortic Valve Replacement

Abstract

Background: Acute kidney injury (AKI) can be a major complication of transcatheter aortic valve replacement (TAVR). Atheroembolization of debris during catheter manipulation has been considered as a potential factor causing AKI. This study investigates the impact of aortic atheroma burden on AKI post-TAVR and evaluates the potential of preoperative multislice computed tomographic (MSCT) imaging for the assessment of AKI in these patients.

Methods and results: Preoperative multislice computed tomographic images were analyzed in 278 patients with symptomatic severe aortic stenosis who underwent TAVR. AKI was defined as an absolute increase in serum creatinine ≥0.3 mg/dL. Aorta vessel and lumen areas in each 1-mm cross-sectional image were measured. Percent atheroma volume above (PAV_{above renal arteries}) and below (PAV_{below renal arteries}) renal arteries were calculated by the following formula: PAV={Σ (vessel area-lumen area)/Σ(vessel area)}×100. AKI occurred in 92 patients (33.1%) after TAVR. AKI was associated with a greater PAV above (30.4±8.2 versus 21.3±5.8%; P=0.02) but not below (28.9±7.7 versus 25.8±6.1%; P=0.41) the renal arteries. Greater PAV_{above renal arteries} was associated directly with AKI severity ( P=0.008) and inversely with recovery in serum creatinine level from peak to discharge ( r=0.78; P=0.002). Multivariate analysis demonstrated that PAV_{above renal arteries} was a significant predictor of AKI ( P=0.02). Receiver-operating curve analysis identified PAV_{above renal arteries} >29.5% as an optimal threshold to predict AKI.

Conclusions: Suprarenal aortic atheroma burden is associated with the occurrence, severity, and recovery of AKI after TAVR. This highlights the utility of preoperative assessment of aortic atherosclerosis on multislice computed tomography to identify patients at high-risk for AKI.

Keywords: acute kidney injury; aorta; atherosclerosis; renal artery; transcatheter aortic valve replacement.