First direct comparison of clinical outcomes between European and Asian cohorts in transcatheter aortic valve implantation: the Massy study group vs. the PREVAIL JAPAN trial

Background: The efficacy and safety of transcatheter aortic valve implantation (TAVI) in Asian populations were unknown. The purpose of this study was to compare directly the clinical outcomes of the first Japanese trial and a European single-center experience after TAVI.

Methods and results: Between April 2010 and October 2011, 64 patients were included in the PREVAIL JAPAN multicenter trial which was set up to evaluate the safety and efficacy of the Edwards SAPIEN XT™ (Edwards Lifesciences, Irvine, CA, USA) in high-risk Japanese patients with severe aortic stenosis. Between March 2010 and January 2012, 237 consecutive patients treated with TAVI using the Edwards SAPIEN XT™ prosthesis at Institut Cardiovasculaire Paris Sud were prospectively included in the Massy cohort. We compared the clinical outcomes of these two cohorts. Patients were of similar age (83.4±6.6 years vs. 84.5±6.1 years, p=0.25), but logistic EuroSCORE was higher in the Massy cohort (20.2±11.7% vs. 15.6±8.0%, p<0.01). Body surface area was smaller in the PREVAIL JAPAN cohort (1.41±0.14m(2) vs. 1.72±0.18m(2); p<0.01) as was the annulus diameter (20.4±1.46mm vs. 22.0±1.84mm, p<0.01). The transfemoral approach was used in 57.8% in the Japanese cohort vs. 51.5% in the Massy cohort. Device success was similar (89.1% vs. 94.1%, p=0.21, respectively), as well as 30-day and 6-month survival rates (92.2% vs. 90.7% and 89.1% vs. 83.1%, p=0.71 and p=0.25, respectively). The incidence of major vascular complications was not significantly different between the two groups (9.4% vs. 5.9%, p=0.23, respectively). A higher post-procedural mean pressure gradient was observed in the PREVAIL JAPAN cohort (12.7±11.4mmHg vs. 10.1±3.6mmHg, p=0.01), but satisfactory improvement in 6-month functional status was obtained in both cohorts (76.5% vs. 77.2%, p=0.91).

Conclusions: Clinical outcomes after TAVI in the patients included in the PREVAIL JAPAN trial were acceptable and as safe as that of a single-center European cohort.