title: Doppler-based renal resistance index for the detection of acute kidney injury and the non-invasive evaluation of paravalvular aortic regurgitation after transcatheter aortic valve implantation.
abstract: OBJECTIVE
  Acute kidney injury (AKI) is a strong but rather late predictor of mortality after transcatheter aortic valve implantation (TAVI). Early clinically useful markers for the detection of AKI and prediction of outcome are needed in order to control and improve management of periprocedural complications after TAVI. The aim of our study was to assess the predictive value of the Doppler-based renal resistance index (RRI), which correlates inversely with effective renal blood flow and creatinine clearance, for AKI in patients undergoing TAVI and to evaluate its association with paravalvular aortic regurgitation (PAR).
  
  
  RESULTS
  TAVI was performed with the Medtronic CoreValve prosthesis in 132 consecutive high-risk patients (mean logistic EuroSCORE: 30.3±18.2%). RRI, serum creatinine and cystatin C level were determined before, and 4 hrs, 24 hrs, 48 hrs, 72 hrs, and 7 days after TAVI. AKI occurred in 32/132 patients (24.2%). While serum creatinine and cystatin C levels decreased at first after TAVI (also in most patients developing AKI), the RRI increased significantly immediately after the procedure from 0.79±0.09 to 0.87±0.12 in patients developing AKI (p=0.003). A RRI >0.85 predicted post-interventional AKI with a sensitivity of 58% and specificity of 86%, and was superior to the serum creatinine level (p<0.001). In addition, an elevated RRI was significantly related to haemodynamic changes after TAVI and was associated with the occurrence of moderate/severe PAR (p<0.001).
  
  
  CONCLUSIONS
  Measurement of the Doppler-based RRI predicts risk for AKI and increased mortality rates at an early post-procedural time point and is related to the occurrence of more-than-mild paravalvular aortic regurgitation after TAVI.
authors.affiliation: Heart Center Bonn, Department of Medicine II, University Hospital Bonn, Bonn, Germany.
authors.forename: Jan-Malte
authors.initials: JM
authors.lastname: Sinning
authors.forename: Viktoria
authors.initials: V
authors.lastname: Adenauer
authors.forename: Anne-Cathérine
authors.initials: AC
authors.lastname: Scheer
authors.forename: Sisa Josefina
authors.initials: SJ
authors.lastname: Lema Cachiguango
authors.forename: Alexander
authors.initials: A
authors.lastname: Ghanem
authors.forename: Christoph
authors.initials: C
authors.lastname: Hammerstingl
authors.forename: Alexander
authors.initials: A
authors.lastname: Sedaghat
authors.forename: Cornelius
authors.initials: C
authors.lastname: Müller
authors.forename: Mariuca
authors.initials: M
authors.lastname: Vasa-Nicotera
authors.forename: Eberhard
authors.initials: E
authors.lastname: Grube
authors.forename: Georg
authors.initials: G
authors.lastname: Nickenig
authors.forename: Nikos
authors.initials: N
authors.lastname: Werner
mesh_terms: D058186:Acute Kidney Injury / Q000175:diagnosis* / Q000401:mortality; D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000601:surgery*; D001022:Aortic Valve Insufficiency / Q000175:diagnosis*; D015415:Biomarkers; D006328:Cardiac Catheterization; D005260:Female; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects*; D006801:Humans; D007668:Kidney / Q000098:blood supply; D008297:Male; D011446:Prospective Studies; D014655:Vascular Resistance / Q000502:physiology*
chemical_list: D015415:Biomarkers