title: The freestyle valve as a right ventricle to pulmonary artery conduit. A systematic review and meta-analysis.
abstract: BACKGROUND
  Reconstruction of the right ventricular outflow tract is the most commonly performed valve repair/replacement procedure in congenital cardiac surgery. There is an ongoing shortage of homografts, and existing bioprosthetic options suffer from substantial rates of structural valve deterioration over time. The Medtronic Freestyle valve is used extensively in the aortic position, but little data is available on its performance in the pulmonary position.
  
  
  METHODS
  A systematic review and meta-analysis of primary studies reporting echocardiographic and clinical outcomes, including reintervention and functional status, associated with the Freestyle valve in the pulmonary position for both Ross and congenital surgery.
  
  
  RESULTS
  13 observational studies including 334 patients with a mean follow-up of 34 months (range 10-98 months) fulfilled the eligibility criteria and were included in the review. Structural valve deterioration occurred in 4.8% (95% confidence interval 0.8-10.6%) of patients. Reintervention was required in 1.1% (95% confidence interval 0.0-3.3%). Freedom from symptoms of heart failure occurred in 97.7% (94.6-99.7%). The results did not change substantially when analysed according to Ross or congenital surgery.
  
  
  CONCLUSIONS
  The Freestyle valve performs well at short-term follow-up and provides a viable alternative when homografts are unavailable. Further long-term studies are required to better assess its role in right ventricular outflow tract reconstruction.
authors.affiliation: Western Australian Cardiothoracic Research and Audit Group, Department of Cardiothoracic Surgery, Royal Perth Hospital, Perth, Western Australia.
authors.forename: Ben
authors.initials: B
authors.lastname: Dunne
authors.affiliation: Western Australian Cardiothoracic Research and Audit Group, Department of Cardiothoracic Surgery, Royal Perth Hospital, Perth, Western Australia.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Suthers
authors.affiliation: Western Australian Cardiothoracic Research and Audit Group, Department of Cardiothoracic Surgery, Royal Perth Hospital, Perth, Western Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Xiao
authors.affiliation: Western Australian Cardiothoracic Research and Audit Group, Department of Cardiothoracic Surgery, Royal Perth Hospital, Perth, Western Australia.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Xiao
authors.affiliation: Western Australian Cardiothoracic Research and Audit Group, Department of Cardiothoracic Surgery, Royal Perth Hospital, Perth, Western Australia.
authors.forename: Edward
authors.initials: E
authors.lastname: Litton
authors.affiliation: Western Australian Cardiothoracic Research and Audit Group, Department of Cardiothoracic Surgery, Royal Perth Hospital, Perth, Western Australia.
authors.forename: David
authors.initials: D
authors.lastname: Andrews
keywords: Ross procedure; freestyle valve; pulmonary valve replacement; right ventricular outflow tract reconstruction; tetralogy of Fallot
references.citation: Lancet. 1966 Dec 31;2(7479):1446-7
references.pmid: 4163445
references.citation: Ann Thorac Surg. 2003 Dec;76(6):1889-94; discussion 1894-5
references.pmid: 14667606
references.citation: Ann Thorac Surg. 2008 Jan;85(1):195-8
references.pmid: 18154809
references.citation: Eur J Cardiothorac Surg. 2013 Jul;44(1):e32-9
references.pmid: 23509232
references.citation: Thorac Cardiovasc Surg. 2009 Aug;57(5):257-69
references.pmid: 19629887
references.citation: Ann Thorac Surg. 2010 Oct;90(4):1295-300
references.pmid: 20868832
references.citation: J Thorac Cardiovasc Surg. 2005 Aug;130(2):282-6
references.pmid: 16077388
references.citation: Eur J Cardiothorac Surg. 2005 Aug;28(2):211-6; discussion 216
references.pmid: 15953733
references.citation: Artif Organs. 2002 Dec;26(12):1055-9
references.pmid: 12460385
references.citation: Ann Thorac Surg. 2011 Feb;91(2):561-5
references.pmid: 21256315
references.citation: J Card Surg. 2011 Nov;26(6):643-9
references.pmid: 21951211
references.citation: Eur J Cardiothorac Surg. 2009 Apr;35(4):600-4; discussion 604-5
references.pmid: 19211257
references.citation: J Thorac Cardiovasc Surg. 1999 Jan;117(1):141-6; discussion 46-7
references.pmid: 9869768
references.citation: Circulation. 2010 Aug 3;122(5):507-16
references.pmid: 20644013
references.citation: Asian Cardiovasc Thorac Ann. 2003 Mar;11(1):58-62
references.pmid: 12692025
references.citation: J Thorac Cardiovasc Surg. 2011 Aug;142(2):351-8
references.pmid: 21281951
references.citation: Eur J Cardiothorac Surg. 2012 Dec;42(6):988-95
references.pmid: 22491670
references.citation: Ann Thorac Surg. 2002 Sep;74(3):684-8
references.pmid: 12238824
references.citation: J Heart Valve Dis. 2006 Sep;15(5):696-701
references.pmid: 17044377
references.citation: Eur J Cardiothorac Surg. 2012 Dec;42(6):927-33
references.pmid: 22621871
references.citation: Eur J Cardiothorac Surg. 2012 Jul;42(1):e1-8
references.pmid: 22561653
references.citation: Eur J Cardiothorac Surg. 2008 Apr;33(4):523-8
references.pmid: 18313319
references.citation: Circ Cardiovasc Interv. 2014 Jun;7(3):374-80
references.pmid: 24867892
references.citation: World J Pediatr Congenit Heart Surg. 2014 Oct;5(4):534-40
references.pmid: 25324250
references.citation: Ann Thorac Surg. 2003 Dec;76(6):1896-900
references.pmid: 14667607
references.citation: Ann Thorac Surg. 2011 Jul;92 (1):183-90; discussion 190-2
references.pmid: 21549348
references.citation: J Heart Valve Dis. 2006 Jan;15(1):92-6
references.pmid: 16480018
references.citation: Ann Thorac Surg. 2001 May;71(5 Suppl):S361-4
references.pmid: 11388224
references.citation: Semin Thorac Cardiovasc Surg. 2001 Oct;13(4 Suppl 1):24-7
references.pmid: 11805945
references.citation: J Heart Valve Dis. 1996 Jul;5(4):418-20
references.pmid: 8858507
references.citation: Circ Cardiovasc Interv. 2012 Dec;5(6):862-70
references.pmid: 23212395
references.citation: Ann Thorac Surg. 2004 May;77(5):1711-6
references.pmid: 15111172