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Purpose: Transcatheter aortic valve implantation (TAVI) for severe aortic stenosis improves survival in patients deemed unsuitable for surgical aortic valve replacement. Adverse outcomes after TAVI have been linked to acute kidney injury (AKI) and strategies to prevent this may improve overall outcomes. We hypothesised that transoesophageal echocardiography (TOE) guidance during transfemoral and apical approaches for TAVI would minimise contrast doses and related AKI.Method: We evaluated the use of TOE guidance using the Philips iE33 platform with the X7-2t matrix array probe. Glomerular filtration rates were estimated (eGFR) using the Cockroft-Gault formula and classification of chronic kidney disease (CKD) based on K/DOQI working group recommendations with class 1 representing normal renal function and class 5 end stage renal failure. AKI was defined as >50% reduction from baseline eGFR. Iopamidol with an equivalent of 370 mg iodine/ml (Niopam 370, Bracco Ltd) was used during angiography. Image acquisition, data storage and analysis were performed in accordance with departmental protocols.Results (standard deviation, range): 56 of 57 patients (98%) with a mean logistic Euroscore of 22% had an Edwards SAPIEN heart-valve system (Edwards Lifesciences) successfully implanted at our institution between 2008 and 2011. Mean age was 82.5 (6.8, 68.1-94) years, 39% were male. Approach was transfemoral in 68%. Before TAVI none of the patients had normal renal function. 14, 61, 23, and 2% of patients were in CKD class 2, 3, 4 and 5 respectively. Mean follow-up was 1.46 years (0.82, 0.19-2.73). Overall survival was 72% with 4 procedural and 6 early deaths (<30 days). TOE guidance was achieved in all TAVI recipients and minimised contrast doses to a mean of 1.8 ml/kg. In 53 patients who survived the initial TAVI procedure, AKI was seen in one patient (2%) and chronic worsening of CKD class in 8 (15%). Of the two patients progressing to CKD class 5, one was already established on haemodialysis while the other died early after TAVI due to multi-organ dysfunction.Conclusion: TOE guidance during TAVI is feasible and minimises contrast use during apical and transfemoral approaches. The risk of AKI appears low when using this technique. This imaging modality may ultimately eliminate the need for nephrotoxic contrast agents and improve TAVI outcomes.