title: Severe symptomatic aortic stenosis: medical therapy and transcatheter aortic valve implantation (TAVI)-a real-world retrospective cohort analysis of outcomes and cost-effectiveness using national data.
abstract: Determine the real-world difference between 2 groups of patients with severe aortic stenosis and similar baseline comorbidities: surgical turn down (STD) patients, who were managed medically prior to the availability of transcatheter aortic valve implantation (TAVI) following formal surgical outpatient assessment, and patients managed with a TAVI implant.
  
  
  
  Retrospective cohort study from real-world data.
  
  
  
  Electronic patient letters were searched for patients with a diagnosis of severe aortic stenosis and a formal outpatient STD prior to the availability of TAVI (1999-2009). The second group comprised the first 90 cases of TAVI in South Wales (2009 onwards). 2 years prior to and 5 years following TAVI/STD were assessed. Patient data were pseudoanonymised, using the Secure Anonymized Information Linkage (SAIL) databank, and extracted from Office National Statistics (ONS), Patient-Episode Database for Wales (PEDW) and general practitioner databases.
  
  
  
  90 patients who had undergone TAVI in South Wales, and 65 STD patients who were medically managed.
  
  
  
  Survival, hospital admission frequency and length of stay, primary care visits, and cost-effectiveness.
  
  
  
  TAVI patients were significantly older (81.8 vs 79.2), more likely to be male (59.1% vs 49.3%), baseline comorbidities were balanced. Mortality in TAVI versus STD was 28% vs 70% at 1000 days follow-up. There were significantly more hospital admissions per year in the TAVI group prior to TAVI/STD (1.5 (IQR 1.0-2.4) vs 1.0 IQR (0.5-1.5)). Post TAVI/STD, the TAVI group had significantly lower hospital admissions (0.3 (IQR 0.0-1.0) vs 1.2 (IQR 0.7-3.0)) and lengths of stay (0.4 (IQR 0.0-13.8) vs 11.0 (IQR 2.5-28.5), p<0.05). The incremental cost-effectiveness ratio (ICER) for TAVI was £10 533 per quality-adjusted life year (QALY).
  
  
  
  TAVI patients were more likely to survive and avoid hospital admissions compared with the medically managed STD group. The ICER for TAVI was £10 533 per QALY, making it a cost-effective procedure.
authors.affiliation: Division of Population Medicine, Cardiff University, Cardiff, UK; Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark.
authors.forename: Phillip M
authors.identifier: 0000-0003-1769-251X
authors.initials: PM
authors.lastname: Freeman
authors.affiliation: Division of Population Medicine , Cardiff University , Cardiff , UK.
authors.forename: Majd B
authors.identifier: 0000-0001-8992-9120
authors.initials: MB
authors.lastname: Protty
authors.affiliation: Morriston Hospital , Swansea , UK.
authors.forename: Omar
authors.initials: O
authors.lastname: Aldalati
authors.affiliation: Swansea University , Swansea , UK.
authors.forename: Arron
authors.initials: A
authors.lastname: Lacey
authors.affiliation: Division of Population Medicine , Cardiff University , Cardiff , UK.
authors.forename: William
authors.initials: W
authors.lastname: King
authors.affiliation: University Hospital of Wales , Cardiff , UK.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Anderson
authors.affiliation: Morriston Hospital, Swansea, UK; Swansea University, Swansea, UK.
authors.forename: Dave
authors.initials: D
authors.lastname: Smith