European Journal of Cardio-Thoracic Surgery 0 (2018) 1 LETTER TO THE EDITOR RESPONSE dimension parameters, with no remarkable change in results, which leads us to believe the model was correctly speciﬁed. Altogether, we agree that it is premature to conclude about the superiority a,b a,b a,b,c Rui J. Cerqueira ,Ma´rio Jorge Amorim , Andre´ P. Lourenc¸o and of one valve over another: certainly, a bioprosthesis is more than just its a,b, Adelino Leite-Moreira * haemodynamics. What we can say is that Trifecta shows a stentless-like behav- Department of Surgery and Physiology, Faculty of Medicine, University of iour, which has actually also been demonstrated by Rubens et al.  in a very Porto, Porto, Portugal elegant paper comparing it against a classic stented valve. ~ ~ Department of Cardiothoracic Surgery, Sao Joao Hospital Centre, Porto, Portugal ~ ~ Department of Anaesthesiology, Sao Joao Hospital Centre, Porto, Portugal REFERENCES Received 14 March 2018; accepted 18 March 2018  Ngu JMC, Rubens FD, Burwash IG. Six of one is not half a dozen of the other. Eur J Cardiothorac Surg 2018;doi:10.1093/ejcts/ezy144. Keywords: Aortic valve replacement � Bioprostheses � Haemodynamic  Cerqueira RJ, Raimundo R, Moreira S, Saraiva FA, Andrade M, Salgueiro E et al. Freedom Solo(R) versus Trifecta(R) bioprostheses: clinical and We read with great interest the letter to the editor by Ngu et al.  addressing haemodynamic evaluation after propensity score matching. Eur J V R V R 2 major limitations of our article comparing Freedom Solo and Trifecta bio- Cardiothorac Surg 2018; doi:10.1093/ejcts/ezx472. prostheses . We appreciate the authors’ comments and agree that these  Holzhey D, Mohr FW, Walther T, Mollmann H, Beckmann A, Kotting J should be taken under consideration while interpreting our results. et al. Current results of surgical aortic valve replacement: insights from Our main goal was to perform a comparison of valve performance in a real- the German Aortic Valve Registry. Ann Thorac Surg 2016;101:658–66. world scenario and not speciﬁcally on pure aortic stenosis. Although the  Brookhart MA, Schneeweiss S, Rothman KJ, Glynn RJ, Avorn J, Sturmer T. prevalence of aortic regurgitation in our sample does not seem particularly Variable selection for propensity score models. Am J Epidemiol 2006; high , we admit that inclusion of aortic regurgitation patients might have 163:1149–56. biased the analysis of reverse ventricular remodelling after aortic valve re-  Rubens FD, Gee YY, Ngu JM, Chen L, Burwash IG. Effect of aortic pericar- placement. The suggested subanalysis is undoubtly appropriate and we did in dial valve choice on outcomes and left ventricular mass regression in pa- fact ﬁnd a trend towards a faster decline in left ventricular mass in pure aortic tients with left ventricular hypertrophy. J Thorac Cardiovasc Surg 2016; stenosis patients after aortic valve replacement with the Trifecta bioprosthesis. 152:1291–8.e2. However, our study is underpowered for that matter and this could, therefore, at most, be a question for future works. A second word of caution was raised regarding propensity score model *Corresponding author. Departamento de Cirurgia e Fisiologia, Unidade de building. This is indeed a critical point, since the best way to choose the cova- ~ Investigac¸ao Cardiovascular, Faculdade de Medicina da Universidade do Porto, riates is far from settled. We used a prespeciﬁed list of variables that were Alameda Prof. Herna ˆ ni Monteiro, 4200-319 Porto, Portugal. Tel: +351-22- associated with the outcome but not necessarily with the exposure, as sug- 5513644; fax: +351-22-5513646; e-mail: firstname.lastname@example.org (A. Leite-Moreira). gested by Brookhart et al.  for small datasets. Additionally, several iterations of the propensity score model were tried, with the inclusion of ventricular doi:10.1093/ejcts/ezy145 The Author(s) 2018. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. Downloaded from https://academic.oup.com/ejcts/advance-article-abstract/doi/10.1093/ejcts/ezy145/4962538 by Ed 'DeepDyve' Gillespie user on 12 July 2018 LETTER TO THE EDITOR
European Journal of Cardio-Thoracic Surgery – Oxford University Press
Published: Apr 6, 2018
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