Transcatheter Aortic Valve Implantation - Applications, Populations and Outcomes

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Abstract

Abstract
Treatment of valvular heart disease has entered a new era, in particular with the introduction and more widespread adoption of transcatheter aortic valve implantation (TAVI). Despite excellent long-term results from surgical correction there remain a significant proportion of patients who are denied surgical treatment due to multiple co-morbidities. TAVI now offers a new treatment for patients with severe symptomatic aortic stenosis who would otherwise have a poor prognosis without intervention. We highlight the role for this rapidly evolving technology and, as a an example, present a case scenario with a patient™s journey through a TAVI programme. The limited outcome data are presented and the new state-of-the-art devices are also discussed.

Keywords
Aortic stenosis, transcatheter aortic valve, high-risk, non-coronary intervention, balloon valvuloplasty

Disclosure: The authors have no conflicts of interest to declare.
Received: 16 July 2009 Accepted: 10 August 2009
Correspondence: GW Mikhail, Department of Cardiology, St Mary™s Hospital, Imperial College NHS Trust, Praed Street, London, W2 1NY, UK. E: g.mikhail@btopenworld.com

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Aortic valve stenosis is the most common valve disorder in the general adult population1├óÔé¼ÔÇ£3 and its prevalence increases with age.4,5 If symptomatic and left untreated, it is invariably unilaterally fatal, with mortality rates in patients who are either turned down or decline surgery of 36% at one year, 68% at five years and 82% at 10 years.5,6 In the elderly, who have more co-morbidities such as renal impairment and left ventricular dysfunction, the prognosis is worse. One study demonstrates a 12-fold increase in mortality in octogenarians followed up to 36 months who did not undergo valve replacement. Interestingly, the strongest predictor of mortality in that cohort, by multivariate analysis, was refusal to undergo surgery.7,8 Additionally, a number of studies have also reported that 30├óÔé¼ÔÇ£60% of patients with aortic stenosis are not referred for assessment. This highlights the possible misconceptions of some physicians.5,9

We have seen a paradigm shift in the last five years, namely the emergence of new technologies that can offer alternative percutaneous treatment strategies. This article appraises and informs the reader on the current state-of-the-art devices and techniques available, as well as providing some insights into the newer secondgeneration devices.

References
  1. Nkomo VT, Gardin JM, Skelton TN, et al., Burden of valvular heart diseases: a population-based study, Lancet, 2006;368(9540):1005├óÔé¼ÔÇ£11.
  2. Lung B, Gohlke-Barwolf C, Tornos P, et al., Recommendations on the management of the asymptomatic patient with valvular heart disease, Eur Heart J, 2002;23(16):1252├óÔé¼ÔÇ£66.
  3. Carabello BA, Is it ever too late to operate on the patient with valvular heart disease?, J Am Coll Cardiol, 2004;44(2): 376├óÔé¼ÔÇ£83.
  4. Ross J, Jr., Braunwald E, Aortic stenosis, Circulation, 1968;38(1 Suppl.):61├óÔé¼ÔÇ£7.
  5. Otten AM, van Domburg RT, van Gameren M, et al., Population characteristics, treatment assignment and survival of patients with aortic stenosis referred for percutaneous valve replacement, EuroIntervention, 2008;4(2):250├óÔé¼ÔÇ£55.
  6. Varadarajan P, Kapoor N, Bansal RC, et al., Survival in elderly patients with severe aortic stenosis is dramatically improved by aortic valve replacement: Results from a cohort of 277 patients aged > or =80 years, Eur J Cardiothorac Surg, 2006;30(5):722├óÔé¼ÔÇ£7.
  7. Melby SJ, Zierer A, Kaiser SP, et al., Aortic valve replacement in octogenarians: risk factors for early and late mortality, Ann Thorac Surg, 2007;83(5):1651├óÔé¼ÔÇ£6, discussion 1656├óÔé¼ÔÇ£7.
  8. Kojodjojo P, Gohil N, Barker D, et al., Outcomes of elderly patients aged 80 and over with symptomatic, severe aortic stenosis: impact of patient™s choice of refusing aortic valve replacement on survival, QJM, 2008;101(7): 567├óÔé¼ÔÇ£73.
  9. Vahanian A, Alfieri O, Al-Attar N, et al., Transcatheter valve implantation for patients with aortic stenosis: a position statement from the European Association of Cardio-Thoracic Surgery (EACTS) and the European Society of Cardiology (ESC), in collaboration with the European Association of Percutaneous Cardiovascular Interventions (EAPCI), Eur Heart J, 2008;29(11):1463├óÔé¼ÔÇ£70.
  10. Bailey CP, The surgical treatment of mitral stenosis (mitral commissurotomy), Dis Chest, 1949;15(4):377├óÔé¼ÔÇ£97.
  11. Barrat-Boyes B, Long-term follow-up of aortic valvar grafts, Br Heart J, 1971;(Suppl. 33):60.
  12. Carpentier A, Lemaigre G, Robert L, et al., Biological factors affecting long-term results of valvular heterografts, J Thorac Cardiovasc Surg, 1969;58(4):467├óÔé¼ÔÇ£83.
  13. Vahanian A, Balloon valvuloplasty, Heart, 2001;85(2): 223├óÔé¼ÔÇ£8.
  14. Bonhoeffer P, Boudjemline Y, Saliba Z, et al., Percutaneous replacement of pulmonary valve in a rightventricle to pulmonary-artery prosthetic conduit with valve dysfunction, Lancet, 2000;356(9239):1403├óÔé¼ÔÇ£5.
  15. Cribier A, Eltchaninoff H, Bash A, et al., Percutaneous transcatheter implantation of an aortic valve prosthesis for calcific aortic stenosis: first human case description, Circulation, 2002;106(24):3006├óÔé¼ÔÇ£8.
  16. Serruys PW, Keynote address-EuroPCR 2008, Barcelona, May 14th, 2008. Transcatheter aortic valve implantation: state of the art, EuroIntervention, 2009;4(5):558├óÔé¼ÔÇ£65.
  17. Medtronic announced the 4,000th placement of its CoreValve aortic prosthetic valve. Available at: http://tctmd.com/show.aspx?id=78760
  18. Rankin JS, Hammill BG, Ferguson TB, Jr, et al., Determinants of operative mortality in valvular heart surgery, J Thorac Cardiovasc Surg, 2006;131(3):547├óÔé¼ÔÇ£57.
  19. Goodney PP, O™Connor GT, Wennberg DE, Birkmeyer JD, Do hospitals with low mortality rates in coronary artery bypass also perform well in valve replacement?, Ann Thorac Surg, 2003;76(4):1131├óÔé¼ÔÇ£6, discussion 1136├óÔé¼ÔÇ£7.
  20. Filsoufi F, Rahmanian PB, Castillo JG, et al., Excellent early and late outcomes of aortic valve replacement in people aged 80 and older, J Am Geriatr Soc, 2008;56(2): 255├óÔé¼ÔÇ£61.
  21. Nowicki ER, Birkmeyer NJ, Weintraub RW, et al., Multivariable prediction of in-hospital mortality associated with aortic and mitral valve surgery in Northern New England, Ann Thorac Surg, 2004;77(6): 1966├óÔé¼ÔÇ£77.
  22. Roques F, Nashef SA, Michel P, Risk factors for early mortality after valve surgery in Europe in the 1990s: lessons from the EuroSCORE pilot program, J Heart Valve Dis, 2001;10(5):572├óÔé¼ÔÇ£7, discussion 577├óÔé¼ÔÇ£8.
  23. Surgeons SoT, STS National Database. STS US Cardiac Surgery Database: 1997 Aortic Valve Replacement Patients: Preoperative Risk Variables. Available at: www.ctsnet. org/doc/3031 (accessed 10 May 2006).
  24. Ambler G, Omar RZ, Royston P, et al., Generic, simple risk stratification model for heart valve surgery, Circulation, 2005;112(2):224├óÔé¼ÔÇ£31.
  25. De Belder M, Introducing TAVI in the UK ├óÔé¼ÔÇ£ overcoming the barriers, Cardiology News, 2009;12(5):6├óÔé¼ÔÇ£9.
  26. Wood D, Tops L, Mayo J, et al., Role of Multislice Computed Tomography in Transcatheter Aortic Valve Replacement, Am J Cardiol, 2009;103:1295├óÔé¼ÔÇ£1301.
  27. Thomas M, Transcatheter Aortic Valve Implantation in the United Kingdom: NICE guidance, Heart,1 2009;95:674├óÔé¼ÔÇ£75.
  28. Krajcer Z, Howell M, A Novel Technique Using the Percutaneous Vascular Surgery Device to Close the 22 French Femoral Artery Entry Site Used for Percutaneous Abdominal Aortic Aneurysm Exclusion, Cathet Cardiovasc Interv, 2000;50:356├óÔé¼ÔÇ£60
  29. Cutlip DE, Windecker S, Mehran R, et al., on behalf of the Academic Research C. Clinical End Points in Coronary Stent Trials: A Case for Standardized Definitions, Circulation, 2007;115(17):2344├óÔé¼ÔÇ£51.
  30. Piazza N, Cutlip DE, Onuma Y, et al., Clinical endpoints in transcatheter aortic valve implantation: a call to ARC for standardised definitions, EuroIntervention, 2009;5:29├óÔé¼ÔÇ£31.
  31. Rosengart T, Feldman T, Borger M, et al., Percutanous and minimally invasive valve procedures. A scientific statement from the American Heart Association Council on Cardiovascular Surgery and Anasthaesia, Council on Clinical Cardiology, Functional Genomics and Translational Biology Interdisciplinary Working Group, and Quality of Care and Outcomes Research Interdisciplinary Working Group, Circulation, 2008;117:1750├óÔé¼ÔÇ£67.
  32. Haworth P, Behan M, Hutchinson N, et al., Electrocardiographic Changes After Insertion of CoreValve Aortic Valve Revalving System, EuroIntervention, 2009;5(Suppl E):51.
  33. Low R, Bolling S, Yeo K, Ebner A, Direct Flow Medical Percutaneous Aortic valve: proof of concept, EuroIntervention, 2008;4:256-261.
  34. Bullesfeld L, Gerckens U, Grube E, Percutaneous implantation of the first repositionable aortic valve prosthesis in a patient with severe aortic stenosis, Cathet Cardiovasc Interv, 2008;71:579├óÔé¼ÔÇ£84.