title: Minimally invasive transapical aortic valve implantation and the risk of acute kidney injury.
abstract: BACKGROUND
  The new technique of minimally invasive transapical aortic valve implantation (TAP-AVI) deals with high-risk patients and despite the absence of cardiopulmonary bypass it might lead to renal impairment. The aim of this study was to estimate the risk of the development of acute kidney injury (AKI) after TAP-AVI and to identify possible risk factors with regard to the morbidity and mortality of the patients.
  
  
  METHODS
  Data of 30 consecutive patients undergoing TAP-AVI were recorded and followed up for 8 weeks. Postoperative AKI has been defined according to RIFLE criteria. Two patients on chronic hemodialysis have been followed up.
  
  
  RESULTS
  Of 28 patients, AKI occurred in 16 patients (57%). Statistical analysis revealed no influence on the risk of developing AKI caused by the dose of applicated contrast medium (p = 0.09), the patient's age (p = 0.5), or the existence of diabetes (p = 0. 16). Analysis concerning the relationship between a preexisting coronary heart disease and AKI showed a tendency to be associated with a higher risk of the development of AKI (70% preexisting congenital heart disease in the AKI group versus 50%; p = 0.28). Only a preoperative serum creatinine greater than 1.1 mg/dL was a strong predictor for developing AKI (p < 0.01). Length of stay in the intensive care unit and the complete length of hospital stay revealed no difference with regard to postoperative development of AKI though statistical analysis showed a trend to a higher mortality in the AKI group (27% vs 6%); univariate analysis did not reach statistical significance (p = 0.13).
  
  
  CONCLUSIONS
  The TAP-AVI seems to be a feasible procedure for high-risk patients with a clear risk of developing AKI. Patients at risk should be identified and, if indicated, already preoperatively treated in collaboration with the attending nephrologists.
authors.affiliation: Department of Cardiothoracic Surgery, University Hospital of Cologne, Cologne, Germany. justus.strauch@uk-koeln.de
authors.forename: Justus T
authors.initials: JT
authors.lastname: Strauch
authors.forename: Maximilian P
authors.initials: MP
authors.lastname: Scherner
authors.forename: Peter L
authors.initials: PL
authors.lastname: Haldenwang
authors.forename: Roman
authors.initials: R
authors.lastname: Pfister
authors.forename: Elmar W
authors.initials: EW
authors.lastname: Kuhn
authors.forename: Navid
authors.initials: N
authors.lastname: Madershahian
authors.forename: Parwis
authors.initials: P
authors.lastname: Rahmanian
authors.forename: Jens
authors.initials: J
authors.lastname: Wippermann
authors.forename: Thorsten
authors.initials: T
authors.lastname: Wahlers
mesh_terms: D058186:Acute Kidney Injury / Q000175:diagnosis / Q000209:etiology* / Q000401:mortality; D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000601:surgery*; D001705:Bioprosthesis; D006328:Cardiac Catheterization; D002315:Cardiopulmonary Bypass; D015897:Comorbidity; D003404:Creatinine / Q000097:blood; D004452:Echocardiography; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D008297:Male; D019060:Minimally Invasive Surgical Procedures / Q000379:methods*; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology* / Q000401:mortality; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate
chemical_list: D003404:Creatinine