title: Learning curves for transfemoral transcatheter aortic valve replacement in the PARTNER-I trial: Success and safety.
abstract: OBJECTIVE
  To identify number of cases needed to maximize device success and minimize adverse events after transfemoral transcatheter aortic valve replacement (TF-TAVR), and determine if adverse events were linked to the technical performance learning curve.
  
  
  BACKGROUND
  TF-TAVR is a complex procedure with an incompletely characterized learning curve for clinical outcomes.
  
  
  METHODS
  From 4/2007-2/2012, 1521 patients underwent TF-TAVR in the PARTNER-I trial. Outcomes learning curves were defined as number of cases needed to reach a plateau for device success, adverse events, and post-procedure length of stay. Institutional variation was accounted for by mixed-model non-linear techniques, which were also used to identify contribution of the procedure time learning curve to 30-day major adverse events and length of stay.
  
  
  RESULTS
  Eighty percent device success was achieved after 22 cases; major vascular complications fell below 5% after 70 cases and major bleeding below 10% after 25 cases. It took an average of 28 cases to achieve a consistent low risk of 30-day major adverse events, but institutions entering in the middle of the trial achieved it after about 26. The most significant correlate of 30-day major adverse events and post-procedure length of stay was procedure time (P < 0.0001). However, this association was related to patient and unmeasured variables, not the procedure time learning curve (P = 0.6).
  
  
  CONCLUSIONS
  By end of trial, a consistent low risk of adverse events was achieved after ∼26 cases. However, these improved results were due to change in patient risk profile; outcomes were not linked to the technical performance learning curve. © 2015 Wiley Periodicals, Inc.
authors.affiliation: MedStar Washington Hospital Center, Washington, DC.
authors.forename: Sa'ar
authors.initials: S
authors.lastname: Minha
authors.affiliation: MedStar Washington Hospital Center, Washington, DC.
authors.forename: Ron
authors.initials: R
authors.lastname: Waksman
authors.affiliation: MedStar Washington Hospital Center, Washington, DC.
authors.forename: Lowell P
authors.initials: LP
authors.lastname: Satler
authors.affiliation: MedStar Washington Hospital Center, Washington, DC.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Torguson
authors.affiliation: University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Oluseun
authors.initials: O
authors.lastname: Alli
authors.affiliation: Mayo Clinic, Rochester, Minnesota.
authors.forename: Charanjit S
authors.initials: CS
authors.lastname: Rihal
authors.affiliation: Baylor Scott & White Health, Plano, Texas.
authors.forename: Michael
authors.initials: M
authors.lastname: Mack
authors.affiliation: PARTNER Publications Office.|Cleveland Clinic, Cleveland, Ohio.
authors.forename: Lars G
authors.initials: LG
authors.lastname: Svensson
authors.affiliation: PARTNER Publications Office.|Cleveland Clinic, Cleveland, Ohio.
authors.forename: Jeevanantham
authors.initials: J
authors.lastname: Rajeswaran
authors.affiliation: PARTNER Publications Office.|Cleveland Clinic, Cleveland, Ohio.
authors.forename: Eugene H
authors.initials: EH
authors.lastname: Blackstone
authors.affiliation: Cleveland Clinic, Cleveland, Ohio.
authors.forename: E Murat
authors.initials: EM
authors.lastname: Tuzcu
authors.affiliation: Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Vinod H
authors.initials: VH
authors.lastname: Thourani
authors.affiliation: Cedars Sinai Medical Center, Los Angeles, California.
authors.forename: Raj
authors.initials: R
authors.lastname: Makkar
authors.affiliation: Cleveland Clinic, Cleveland, Ohio.
authors.forename: John
authors.initials: J
authors.lastname: Ehrlinger
authors.affiliation: Cleveland Clinic, Cleveland, Ohio.
authors.forename: Ashley M
authors.initials: AM
authors.lastname: Lowry
authors.affiliation: Cleveland Clinic, Cleveland, Ohio.
authors.forename: Rakesh M
authors.initials: RM
authors.lastname: Suri
authors.affiliation: Mayo Clinic, Rochester, Minnesota.
authors.forename: Kevin L
authors.initials: KL
authors.lastname: Greason
authors.affiliation: PARTNER Publications Office.|Columbia University Medical Center/New York-Presbyterian Hospital, New York, New York.
authors.forename: Martin B
authors.initials: MB
authors.lastname: Leon
authors.affiliation: Mayo Clinic, Rochester, Minnesota.
authors.forename: David R
authors.initials: DR
authors.lastname: Holmes
authors.affiliation: MedStar Washington Hospital Center, Washington, DC.
authors.forename: Augusto D
authors.initials: AD
authors.lastname: Pichard
mesh_terms: D000369:Aged, 80 and over; D001021:Aortic Valve / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000601:surgery*; D004503:Education, Medical, Graduate / Q000379:methods*; D005260:Female; D005263:Femoral Artery; D006350:Heart Valve Prosthesis; D006801:Humans; D059032:Learning Curve; D008297:Male; D012189:Retrospective Studies; D012720:Severity of Illness Index; D065467:Transcatheter Aortic Valve Replacement / Q000193:education* / Q000379:methods; D016896:Treatment Outcome
keywords: adverse events; device success; outcomes learning curves; transcatheter aortic valve replacement; transfemoral