飯塚 大介¹, 坂口 大和¹, 牧野 仁人¹, 高橋 茉理瑛¹, 佐野 拓真¹, 田口 重文¹, 倉持 雄彦¹, 桃原 哲也¹, 大内 厚太郎²

Daisuke IIDUKA¹, Yamato SAKAGUCHI¹, Masato MAKINO¹, Marie TAKAHASHI¹, Takuma SANO¹, Shigefumi TAGUCHI¹, Takehiko KURAMOCHI¹, Tetsuya TOBARU¹, Kotaro OUCHI²

¹千葉西総合病院循環器科, ²東京慈恵会医科大学放射線医学講座

¹Department of Cardiology Chiba-Nishi General Hospital, ²Department of Radiology, The Jikei University School of Medicine

キーワード : Navitor, self-expanding transcatheter heart valve, transcatheter aortic valve implantation, transesophageal echocardiography, transvalvular leakage

自己拡張型TAVI（transcatheter aortic valve implantation）弁の一つであるNavitor留置後に生じる経弁逆流（transvalvular leakage：TVL）の報告は限られており，特に経食道心エコー図（transesophageal echocardiography：TEE）により人工弁内逆流を明瞭に描出した超音波学的報告は極めて少ない．今回，89歳女性の症候性重症大動脈弁狭窄症に対し，全身麻酔下・経大腿アプローチでTAVI（Navitor 25 mm）を施行したところ，留置直後に血行動態悪化を伴う重度大動脈弁逆流を認めた．術中TEEによる評価では，弁周囲逆流所見に乏しく，人工弁中央からの幅広い逆流ジェットを認め，TVLが主体であると判断した．後拡張後も逆流の改善は乏しかったが，SAPIEN 3によるTAV-in-TAVの追加治療後に逆流は消失し，血行動態は安定した．本症例では，術中TEEにより人工弁内からの逆流を明瞭に描出することで，逆流機序の理解に寄与し得た．TAVI後の急性TVL発生時において，TEEは逆流の起始や広がりを評価するための有用なモダリティとなり得る．

Reports of transvalvular leakage （TVL） following implantation of the self-expanding transcatheter aortic valve Navitor are limited, and transesophageal echocardiographic （TEE） case reports clearly demonstrating intraprosthetic regurgitation are exceedingly rare. An 89-year-old woman with symptomatic severe aortic stenosis underwent transfemoral transcatheter aortic valve implantation （TAVI） under general anesthesia using a 25-mm Navitor valve. Immediately after deployment, severe aortic regurgitation with hemodynamic deterioration occurred. Intraoperative TEE revealed minimal paravalvular leakage; a broad regurgitant jet originating from the center of the transcatheter valve was clearly visualized, consistent with predominant transvalvular leakage. Balloon post-dilatation resulted in only marginal improvement. Consequently, a valve-in-valve transcatheter procedure using a SAPIEN 3 valve was performed, completely abolishing the regurgitation and rapidly stabilizing hemodynamics. This case demonstrates that intraoperative TEE can be used to reliably identify intraprosthetic regurgitation of transcatheter valves and elucidate the mechanism of acute severe aortic regurgitation following TAVI. In cases of acute TVL after TAVI, TEE is a valuable modality for determining the origin and severity of regurgitation.