Transcatheter aortic valve replacement: does kidney function affect outcome?

Abstract

Background: Chronic kidney disease is a significant risk factor for mortality as well as acute kidney injury in cardiac surgery. The impact of contrast agent application on outcome is not well described in patients undergoing transcatheter aortic valve implantation.

Methods: We analyzed data of 270 patients who underwent transcatheter aortic valve implantation (TAVI) between September 2008 and March 2012. Acute kidney injury was defined according to modified risk, injury, failure, loss and end-stage renal failure criteria. Patients on chronic hemodialysis were analyzed separately (n = 15). In 129 (47.8%) patients chronic kidney disease was apparent preoperatively. On average, 83.7 (± 32.4) mL of contrast agent were used per patient.

Results: Postoperatively, 41 patients (15.2%) developed acute kidney injury. In 19 patients (7.1%) transient renal replacement therapy was necessary; no chronic hemodialysis was required. Thirty-day-mortality did not differ between patients with or without chronic kidney disease (7.0% vs 7.1%, p = 0.97). Additionally, chronic kidney disease had no influence on the incidence of postoperative acute kidney injury (12.8% vs 20.2%, p = 0.07) or postoperative hemodialysis (5.0% vs 10.5%, p = 0.08). No correlation between the amount of contrast agent applied and the incidence of acute kidney injury could be verified (p = 0.57).

Conclusions: Preoperative chronic kidney disease does not increase the risk of mortality and acute kidney injury after transcatheter aortic valve implantation. Acute kidney injury after TAVI is associated with an elevated risk of mortality. The amount of contrast agent applied intra-procedurally does not affect the risk of acute kidney injury.

Keywords: 35; AKI; BMI; CKD; COPD; Chronic obstructive pulmonary disease; EuroSCORE; European system for cardiac operative risk evaluation; GFR; ICU; LVEF; NKF; National Kidney Foundation; OPCAB; PAOD; PCI; RRT; SAVR; STS score; Society of Thoracic Surgeons score; TAVI; VARC; Valve Academic Research Consortium; acute kidney injury; body mass index; chronic kidney disease; glomerular filtration rate; intensive care unit; left ventricular ejection fraction; off-pump coronary artery bypass surgery; percutaneous coronary intervention; peripheral arterial occlusive disease; renal replacement therapy; surgical aortic valve replacement; transcatheter aortic valve implantation.