A comparison of patient characteristics and 30-day mortality outcomes after transcatheter aortic valve implantation and surgical aortic valve replacement for the treatment of aortic stenosis: a two-centre study

• Published in: EuroIntervention Vol. 5; no. 5; pp. 580 - 588
• Main Authors: PIAZZA, Nicole, VAN GAMEREN, Menno, TAKKENBERG, Jnhanna J. M, VAN DOMBURG, Ron, DE JAEGERE, Peter, SERRUYS, Patrick W, WINDECKER, Stephan, JÜNI, Peter, WENAWESER, Peter, CARREL, Thierry, ONUMA, Yoshinobu, GAHL, Brigitta, HELLIGE, Gerrit, OTTEN, Amber, KAPPETEIN, Arie-Pieter
• Format: Journal Article
• Language: English
• Published: Toulouse Société Europa Edition 01-11-2009
• Subjects: Aged; Aged, 80 and over; Aortic Valve Stenosis - mortality; Aortic Valve Stenosis - surgery; Aortic Valve Stenosis - therapy; Biological and medical sciences; Cardiac Catheterization - adverse effects; Cardiac Catheterization - mortality; Cardiology. Vascular system; Chi-Square Distribution; Confounding Factors (Epidemiology); Endocardial and cardiac valvular diseases; Female; Heart; Heart Valve Prosthesis Implantation - adverse effects; Heart Valve Prosthesis Implantation - mortality; Humans; Logistic Models; Male; Medical sciences; Middle Aged; Netherlands; Odds Ratio; Patient Selection; Propensity Score; Prospective Studies; Risk Assessment; Risk Factors; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Switzerland; Time Factors; Treatment Outcome; Switzerland; Netherlands; Human; transcatheter aortic valve implantation; Aortic stenosis; Prognosis; Adjustment; Mortality; Characteristic; Cardiovascular disease; Implantation; Patient; Risk; Replacement; Treatment; Cardiac valvular disease; Characteristics; Surgery; Risk factor; surgical aortic valve replacement; Day; Aortic valve; Comparative study; risk-adjustment
• ISSN: 1774-024X; 1969-6213
• DOI: 10.4244/EIJV5I5A94

It is unclear whether transcatheter aortic valve implantation (TAVI) addresses an unmet clinical need for those currently rejected for surgical aortic valve replacement (SAVR) and whether there is a subgroup of high-risk patients benefiting more from TAVI compared to SAVR. In this two-centre, prospective cohort study, we compared baseline characteristics and 30-day mortality between TAVI and SAVR in consecutive patients undergoing invasive treatment for aortic stenosis.
We pre-specified different adjustment methods to examine the effect of TAVI as compared with SAVR on overall 30-day mortality: crude univariable logistic regression analysis, multivariable analysis adjusted for baseline characteristics, analysis adjusted for propensity scores, propensity score matched analysis, and weighted analysis using the inverse probability of treatment (IPT) as weights. A total of 1,122 patients were included in the study: 114 undergoing TAVI and 1,008 patients undergoing SAVR. The crude mortality rate was greater in the TAVI group (9.6% vs. 2.3%) yielding an odds ratio [OR] of 4.57 (95%-CI 2.17-9.65). Compared to patients undergoing SAVR, patients with TAVI were older, more likely to be in NYHA class III and IV, and had a considerably higher logistic EuroSCORE and more comorbid conditions. Adjusted OR depended on the method used to control for confounding and ranged from 0.60 (0.11-3.36) to 7.57 (0.91-63.0). We examined the distribution of propensity scores and found scores to overlap sufficiently only in a narrow range. In patients with sufficient overlap of propensity scores, adjusted OR ranged from 0.35 (0.04-2.72) to 3.17 (0.31 to 31.9). In patients with insufficient overlap, we consistently found increased odds of death associated with TAVI compared with SAVR irrespective of the method used to control confounding, with adjusted OR ranging from 5.88 (0.67-51.8) to 25.7 (0.88-750). Approximately one third of patients undergoing TAVI were found to be potentially eligible for a randomised comparison of TAVI versus SAVR.
Both measured and unmeasured confounding limit the conclusions that can be drawn from observational comparisons of TAVI versus SAVR. Our study indicates that TAVI could be associated with either substantial benefits or harms. Randomised comparisons of TAVI versus SAVR are warranted.