title: The Midterm Impact of Transcatheter Aortic Valve Replacement on Surgical Aortic Valve Replacement in Michigan.
abstract: BACKGROUND
  We characterized the midterm impact of transcatheter aortic valve replacement (TAVR) on surgical aortic valve replacement (SAVR) volume, patient profiles, and outcomes in Michigan.
  
  
  METHODS
  We analyzed data obtained after SAVR (n = 15,288) and TAVR (n = 1,783) using the Michigan Society of Thoracic and Cardiovascular Surgery Quality Collaborative from 2006 to 2015. During this period, 17 of 33 hospitals developed TAVR programs.
  
  
  RESULTS
  Annual SAVR volume increased by 38.1% at TAVR hospitals and by 20.4% at non-TAVR hospitals, (p trend < 0.001). In TAVR hospitals, the Society of Thoracic Surgeons (STS) Predicted Risk of Mortality (PROM) decreased before (4.7% ± 5.1%) and after (3.5% ± 3.6%) initiation of TAVR (p < 0.001). Rates of 30-day mortality (pre-TAVR, 3.9% vs post-TAVR, 2.7%; p < 0.001) and renal failure (pre-TAVR, 5.2% vs post-TAVR, 3.3%; p < 0.001) but not stroke (pre-TAVR, 1.9% vs post-TAVR, 1.7%; p = 0.47) were lower after TAVR implementation. Length of stay decreased from 9.0 to 8.5 days (p < 0.001). When analyzing high-risk patients undergoing SAVR (ie, PROM >8%), neither mortality, stroke, nor renal failure was different (all p > 0.15). Despite a reduction in the STS-PROM, non-TAVR hospitals did not display changes in mortality, stroke, or renal failure for either the entire or the high-risk SAVR cohorts after initiation of TAVR in Michigan.
  
  
  CONCLUSIONS
  TAVR implementation in Michigan has dramatically increased overall SAVR volume. This phenomenon has occurred with a concomitant decrease in preoperative risk profile and has improved early SAVR outcomes, particularly at TAVR hospitals, but surprisingly not in patients considered at high preoperative risk. As TAVR use increases, these issues may be further clarified and elucidated.
authors.affiliation: University of Michigan Cardiovascular Center, Ann Arbor, Michigan. Electronic address: hjpatel@med.umich.edu.
authors.forename: Himanshu J
authors.initials: HJ
authors.lastname: Patel
authors.affiliation: Southwest Data Consultants, Dallas, Texas.
authors.forename: Morley A
authors.initials: MA
authors.lastname: Herbert
authors.affiliation: Division of Cardiac Surgery, Henry Ford Hospital, Detroit, Michigan.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Paone
authors.affiliation: Division of Cardiac and Thoracic Surgery, Spectrum Health, Grand Rapids, Michigan.
authors.forename: John C
authors.initials: JC
authors.lastname: Heiser
authors.affiliation: Division of Cardiovascular and Thoracic Surgery, William Beaumont Hospital, Royal Oak, Michigan.
authors.forename: Francis L
authors.initials: FL
authors.lastname: Shannon
authors.affiliation: The Michigan Society of Thoracic and Cardiovascular Surgeons Quality Collaborative, Ann Arbor, Michigan.
authors.forename: Patricia F
authors.initials: PF
authors.lastname: Theurer
authors.affiliation: The Michigan Society of Thoracic and Cardiovascular Surgeons Quality Collaborative, Ann Arbor, Michigan.
authors.forename: Gail F
authors.initials: GF
authors.lastname: Bell
authors.affiliation: University of Michigan Cardiovascular Center, Ann Arbor, Michigan.
authors.forename: Richard L
authors.initials: RL
authors.lastname: Prager
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000601:surgery*; D005260:Female; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D065467:Transcatheter Aortic Valve Replacement / Q000379:methods* / Q000401:mortality