TY - JOUR
T1 - The flaws in the detail of an observational study on transcatheter aortic valve implantation versus surgical aortic valve replacement in intermediate-risks patients
AU - Barili, Fabio
AU - Freemantle, Nick
AU - Folliguet, Thierry
AU - Muneretto, Claudio
AU - de Bonis, Michele
AU - Czerny, Martin
AU - Obadia, Jean Francois
AU - Al-Attar, Nawwar
AU - Bonaros, Nikolaos
AU - Kluin, Jolanda
AU - Lorusso, Roberto
AU - Punjabi, Prakash
AU - Sadaba, Rafael
AU - Suwalski, Piotr
AU - Benedetto, Umberto
AU - Böning, Andreas
AU - Falk, Volkmar
AU - Sousa-Uva, Miguel
AU - Kappetein, Pieter A.
AU - Menicanti, Lorenzo
PY - 2017
Y1 - 2017
N2 - The PARTNER group recently published a comparison between the latest generation SAPIEN 3 transcatheter aortic valve implantation (TAVI) system (Edwards Lifesciences, Irvine, CA, USA) and surgical aortic valve replacement (SAVR) in intermediate-risk patients, apparently demonstrating superiority of the TAVI and suggesting that TAVI might be the preferred treatment method in this risk class of patients. Nonetheless, assessment of the non-randomized methodology used in this comparison reveals challenges that should be addressed in order to elucidate the validity of the results. The study by Thourani and colleagues showed several major methodological concerns: suboptimal methods in propensity score analysis with evident misspecification of the propensity scores (PS; no adjustment for the most significantly different covariates: left ventricular ejection fraction, moderate-severe mitral regurgitation and associated procedures); use of PS quintiles rather than matching; inference on not-adjusted Kaplan-Meier curves, although the authors correctly claimed for the need of balancing score adjusting for confounding factors in order to have unbiased estimates of the treatment effect; evidence of poor fit; lack of data on valve-related death. These methodological flaws invalidate direct comparison between treatments and cannot support authors' conclusions that TAVI with SAPIEN 3 in intermediate-risk patients is superior to surgery and might be the preferred treatment alternative to surgery
AB - The PARTNER group recently published a comparison between the latest generation SAPIEN 3 transcatheter aortic valve implantation (TAVI) system (Edwards Lifesciences, Irvine, CA, USA) and surgical aortic valve replacement (SAVR) in intermediate-risk patients, apparently demonstrating superiority of the TAVI and suggesting that TAVI might be the preferred treatment method in this risk class of patients. Nonetheless, assessment of the non-randomized methodology used in this comparison reveals challenges that should be addressed in order to elucidate the validity of the results. The study by Thourani and colleagues showed several major methodological concerns: suboptimal methods in propensity score analysis with evident misspecification of the propensity scores (PS; no adjustment for the most significantly different covariates: left ventricular ejection fraction, moderate-severe mitral regurgitation and associated procedures); use of PS quintiles rather than matching; inference on not-adjusted Kaplan-Meier curves, although the authors correctly claimed for the need of balancing score adjusting for confounding factors in order to have unbiased estimates of the treatment effect; evidence of poor fit; lack of data on valve-related death. These methodological flaws invalidate direct comparison between treatments and cannot support authors' conclusions that TAVI with SAPIEN 3 in intermediate-risk patients is superior to surgery and might be the preferred treatment alternative to surgery
U2 - https://doi.org/10.1093/ejcts/ezx058
DO - https://doi.org/10.1093/ejcts/ezx058
M3 - Article
C2 - 28531333
SN - 1010-7940
VL - 51
SP - 1031
EP - 1035
JO - European journal of cardio-thoracic surgery
JF - European journal of cardio-thoracic surgery
IS - 6
ER -