title: Learning Alternative Access Approaches for Transcatheter Aortic Valve Replacement: Implications for New Transcatheter Aortic Valve Replacement Centers.
abstract: BACKGROUND
  Smaller transcatheter aortic valve replacement (TAVR) delivery systems have increased the number of patients eligible for transfemoral procedures while decreasing the need for transaortic (TAo) or transapical (TA) access. As a result, newer TAVR centers are likely to have less exposure to these alternative access techniques, making it harder to achieve proficiency. The purpose of this study was to evaluate the learning curve for TAVR approaches and compare perioperative outcomes.
  
  
  METHODS
  From January 2008 to December 2014, 400 patients underwent TAVR (transfemoral, n = 179; TA, n = 120; and TAo, n = 101)). Learning curves were constructed using metrics of contrast utilization, procedural, and fluoroscopy times. Outcomes during the learning curve were compared with after proficiency was achieved.
  
  
  RESULTS
  Depending on the metric, learning curves for all three routes differed slightly but all demonstrated proficiency by the 50th case. There were no significant differences in procedural times whereas improvements in contrast use were most notable for TA (69 ± 40 mL versus 50 ± 23 mL, p = 0.002). For both TA and TAo, fewer patients received transfusions once proficiency was reached (62% versus 34%, p = 0.003, and 42% versus 14%, p = 0.002, respectively). No differences in 30-day or 1-year mortality were seen before or after proficiency was reached for any approach.
  
  
  CONCLUSIONS
  The learning curves for TA and TAo are distinct but technical proficiency begins to develop by 25 cases and becomes complete by 50 cases for both approaches. Given the relatively low volume of alternative access, achieving technical proficiency may take significant time. However, technical proficiency had no effect on 30-day or 1-year mortality for any access approach.
authors.affiliation: Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri.
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Henn
authors.affiliation: Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri.
authors.forename: Thomas
authors.initials: T
authors.lastname: Percival
authors.affiliation: Cardiovascular Division, Department of Medicine, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri.
authors.forename: Alan
authors.initials: A
authors.lastname: Zajarias
authors.affiliation: Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri.
authors.forename: Spencer J
authors.initials: SJ
authors.lastname: Melby
authors.affiliation: Cardiovascular Division, Department of Medicine, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri.
authors.forename: Brian R
authors.initials: BR
authors.lastname: Lindman
authors.affiliation: Cardiovascular Division, Department of Medicine, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri.
authors.forename: Nishath
authors.initials: N
authors.lastname: Quader
authors.affiliation: Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri.
authors.forename: Ralph J
authors.initials: RJ
authors.lastname: Damiano
authors.affiliation: Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri.
authors.forename: Marc R
authors.initials: MR
authors.lastname: Moon
authors.affiliation: Cardiovascular Division, Department of Medicine, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri.
authors.forename: John M
authors.initials: JM
authors.lastname: Lasala
authors.affiliation: Cardiovascular Division, Department of Medicine, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri.
authors.forename: Ravinder S
authors.initials: RS
authors.lastname: Rao
authors.affiliation: Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Bell
authors.affiliation: Cardiovascular Division, Department of Medicine, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri.
authors.forename: Marci S
authors.initials: MS
authors.lastname: Damiano
authors.affiliation: Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, Missouri. Electronic address: maniarh@wudosis.wustl.edu.
authors.forename: Hersh S
authors.initials: HS
authors.lastname: Maniar
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002300:Cardiac Care Facilities; D002983:Clinical Competence; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006301:Health Services Needs and Demand; D006801:Humans; D033183:Interdisciplinary Communication; D000070516:Intersectoral Collaboration; D053208:Kaplan-Meier Estimate; D059032:Learning Curve; D008297:Male; D061646:Operative Time; D018579:Patient Selection; D011183:Postoperative Complications / Q000209:etiology / Q000401:mortality; D012189:Retrospective Studies; D065467:Transcatheter Aortic Valve Replacement / Q000193:education* / Q000295:instrumentation* / Q000379:methods / Q000401:mortality
chemical_list: D003287:Contrast Media