Streamlining the Learning Process for TAVI: Insight From a Comparative Analysis of the OCEAN-TAVI and the Massy Registries Taku Inohara, 1 MD, PhD, Kentaro Hayashida, 1 * MD, PhD, FESC, Yusuke Watanabe, 2 MD, Masanori Yamamoto, 3 MD, PhD, FESC, Kensuke Takagi, 4 MD, Fumiaki Yashima, 1 MD, Takahide Arai, 1,5 MD, Hideyuki Shimizu, 6 MD, PhD, Bernard Chevalier, 5 MD, FESC, FACC, Thierry Lefe ` vre, 5 MD, FESC, FSCAI, Keiichi Fukuda, 1 MD, PhD, FACC, FESC, and Marie-Claude Morice, 5 MD, FESC, FACC Backgrounds: To facilitate the learning process of transcatheter aortic valve implantation (TAVI) in Japan, unique supporting systems (e.g., on-site proctor and web-based screen- ing systems) have been developed. Nevertheless, little is known about real-world clinical outcomes after TAVI in Japan compared with their European counterparts. Methods: From the optimized catheter valvular intervention (OCEAN-TAVI, Japan) and the Institut Cardiovasculaire Paris Sud (Massy, France) registries, we evaluated a total of 134 and 178 patients, respectively, who underwent transfemoral TAVI during the same time period. Results: Among the French cohort, about half of the patients (N 5 81, 45.5%) were treated with the Edwards SAPIEN XT. Body surface area was significantly smaller in the Japanese cohort, although operative risks for both cohorts were almost the same. A greater percentage of patients in the Japanese cohort were implanted with 23 mm valves compared with the French cohort (73.1% vs. 23.0%, P < 0.001), reflecting the smaller annulus diameter (21.8 6 1.6 vs. 23.8 6 2.4 mm, P < 0.001). All-cause 30-day mortality (0% vs. 0.6%, P 5 1.000) and 30-day combined safety endpoint based on the Valve Academic Research Consortium 2 (VARC2) criteria (9.7% vs. 11.2%, P 5 0.713) were similar when limiting the analysis to patients treated with the Edwards SAPIEN XT. Conclusions: Despite the unfavorable aortic anatomy of the Japanese patients, their clinical outcomes after transfemoral TAVI were excellent with the same degree of safety as in an experienced European institute. This minimized learning process achieved the use of unique support systems. V C 2015 Wiley Periodicals, Inc. Key words: transcatheter aortic valve implantation; outcome; ethnicity INTRODUCTION The advent of transcatheter aortic valve implantation (TAVI) has drastically changed the therapeutic options available for high-risk surgical and inoperable patients with severe aortic stenosis (AS). Two landmark randomized controlled trials, the Placement of Aortic Transcatheter Valves (PARTNER) and the CoreValve Pivotal Trial High Risk Study, demonstrated a signifi- cant mortality reduction in inoperable patients with severe AS and similar if not superior survival benefits 1 Department of Cardiology, Keio University School of Medi- cine, Tokyo, Japan 2 Division of Cardiology, Department of Internal Medicine, Tei- kyo University School of Medicine, Tokyo, Japan 3 Division of Cardiovascular Medicine, Toyohashi Heart Center, Toyohashi, Japan 4 Interventional Cardiology Unit, New Tokyo Hospital, Chiba, Japan 5 Department of Interventional Cardiology, Institut Cardiovas- culaire Paris Sud, Massy, France 6 Department of Cardiovascular Surgery, Keio University School of Medicine, Tokyo, Japan Conflict of interest: Dr. Hayashida is a proctor for transfemoral- TAVI for Edwards Lifesciences. Dr. Lefe `vre is a proctor for transfemoral-TAVI for Edwards Lifesciences, and is a consultant for Symetis, Directflow and Medtronic. Dr. Chevalier is a consultant for Medtronic. The other authors report no conflict of interest. *Correspondence: Kentaro Hayashida, MD, PhD, Department of Cardiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. E-mail: k-hayashida@umin.ac.jp Additional Supporting Information may be found in the online ver- sion of this article. Received 20 May 2015; Revision accepted 16 September 2015 DOI: 10.1002/ccd.26266 Published online 22 October 2015 in Wiley Online Library (wileyonlinelibrary.com) V C 2015 Wiley Periodicals, Inc. Catheterization and Cardiovascular Interventions 87:963–970 (2016)