title: Minimally Invasive Versus Conventional Aortic Valve Replacement: A Propensity-Matched Study From the UK National Data.
abstract: OBJECTIVE
  Minimally invasive aortic valve replacement (MIAVR) has been demonstrated as a safe and effective option but remains underused. We aimed to evaluate outcomes of isolated MIAVR compared with conventional aortic valve replacement (CAVR).
  
  
  METHODS
  Data from The National Institute for Cardiovascular Outcomes Research (NICOR) were analyzed at seven volunteer centers (2006-2012). Primary outcomes were in-hospital mortality and midterm survival. Secondary outcomes were postoperative length of stay as well as cumulative bypass and cross-clamp times. Propensity modeling with matched cohort analysis was used.
  
  
  RESULTS
  Of 307 consecutive MIAVR patients, 151 (49%) were performed during the last 2 years of study with a continued increase in numbers. The 307 MIAVR patients were matched on a 1:1 ratio. In the matched CAVR group, there was no statistically significant difference in in-hospital mortality [MIAVR, 4/307,(1.3%); 95% confidence interval (CI), 0.4%-3.4% vs CAVR, 6/307 (2.0%); 95% CI, 0.8%-4.3%; P = 0.752]. One-year survival rates in the MIAVR and CAVR groups were 94.4% and 94.6%, respectively. There was no statistically significant difference in midterm survival (P = 0.677; hazard ratio, 0.90; 95% CI, 0.56-1.46). Median postoperative length of stay was lower in the MIAVR patients by 1 day (P = 0.009). The mean cumulative bypass time (94.8 vs 91.3 minutes; P = 0.333) and cross-clamp time (74.6 vs 68.4 minutes; P = 0.006) were longer in the MIAVR group; however, this was significant only in the cross-clamp time comparison.
  
  
  CONCLUSIONS
  Minimally invasive aortic valve replacement is a safe alternative to CAVR with respect to operative and 1-year mortality and is associated with a shorter postoperative stay. Further studies are required in high-risk (logistic EuroSCORE > 10) patients to define the role of MIAVR.
authors.affiliation: From the *Department of Cardiothoracic Surgery, Guy's and St Thomas' Hospital, London, UK; †Centre for Health Informatics, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK; ‡National Institute for Cardiovascular Outcomes Research, Institute of Cardiovascular Science, University College London, London, UK; §Department of Cardiothoracic Surgery, Manchester Academic Health Science Centre, University Hospital of South Manchester, Wythenshawe, UK; ∥Department of Cardiothoracic Surgery, Morriston Hospital, Morriston, Swansea, UK; ¶Department of Cardiothoracic Surgery North Staffordshire Royal Infirmary, University Hospital of North Staffordshire NHS Trust, Stoke-on-Trent, UK; #Department of Cardiothoracic Surgery, Heart and Lung Centre, New Cross Hospital, Wolverhampton, UK; **Department of Cardiothoracic Surgery, Lancashire Cardiac Centre, Victoria Hospital NHS Trust, Blackpool, UK; ††Department of Cardiothoracic Surgery, Hammersmith Hospital, London, UK; and ‡‡Department of Cardiothoracic Surgery, The Cardiothoracic Centre, Freeman Hospital, Newcastle upon Tyne, UK.
authors.forename: Rizwan Q
authors.initials: RQ
authors.lastname: Attia
authors.forename: Graeme L
authors.initials: GL
authors.lastname: Hickey
authors.forename: Stuart W
authors.initials: SW
authors.lastname: Grant
authors.forename: Ben
authors.initials: B
authors.lastname: Bridgewater
authors.forename: James C
authors.initials: JC
authors.lastname: Roxburgh
authors.forename: Pankaj
authors.initials: P
authors.lastname: Kumar
authors.forename: Paul
authors.initials: P
authors.lastname: Ridley
authors.forename: Moninder
authors.initials: M
authors.lastname: Bhabra
authors.forename: Russell W J
authors.initials: RW
authors.lastname: Millner
authors.forename: Thanos
authors.initials: T
authors.lastname: Athanasiou
authors.forename: Roberto
authors.initials: R
authors.lastname: Casula
authors.forename: Andrew
authors.initials: A
authors.lastname: Chukwuemka
authors.forename: Thasee
authors.initials: T
authors.lastname: Pillay
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Young
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000401:mortality / Q000601:surgery*; D005260:Female; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D017052:Hospital Mortality; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000379:methods*; D057216:Propensity Score; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome