Research to develop new therapies targeting the anatomical substrate involved in the onset, maintenance, and recurrence of ventricular fibrillation

• Project/Area Number: 20K08419
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 53020:Cardiology-related
• Research Institution: Juntendo University (2022-2023); Niigata University (2020-2021)
• Principal Investigator: IIJIMA KENICHI 順天堂大学, 医学部, 准教授 (20625587)
• Co-Investigator(Kenkyū-buntansha): 和泉 大輔 新潟大学, 医歯学系, 助教 (30529699) ; 八木原 伸江 新潟大学, 医歯学総合病院, 特任助教 (70750347) ; 南野 徹 新潟大学, 医歯学系, 教授 (90328063)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Project Status: Completed (Fiscal Year 2023)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2022: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2021: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2020: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
• Keywords: 心室細動 / 心臓突然死 / カテーテルアブレーション / 医師主導治験 / 室間溝 / 電気的除細動 / 植込み型除細動器

Outline of Research at the Start

心臓突然死はわが国でも増加傾向にあり、社会的損失の大きい病態である。その多くは心室細動に代表される致死的心室性不整脈により発生する。現在、心臓突然死予防の中心的役割を果たすのは植込み型除細動器（ICD）治療である。ICD治療の有効性は過去の臨床試験からも明らかであるが、近年、その限界も指摘されている。この限界はICDが心室性不整脈の出現を抑制する機能は持たず対症療法に過ぎないこと、また心室性不整脈の停止に際して侵襲の大きい直流通電を用いることに起因している。本研究は心室細動の発症、維持、再発を直接抑制することによる、ICDへの依存度を低下させた新たな心臓突然死の予防法の確立を目指している。

Outline of Final Research Achievements

Since wavebreak at the junction of the right and left ventricular myocardium (ARVI) is essential for the development of ventricular fibrillation (VF), a preclinical study was conducted to evaluate the efficacy and safety of ablation along the ARVI. Linear ablation along ARVI was performed in normal pigs, and 8 pigs and 4 pigs were kept for 1 month after treatment, and the incidence of VF induction in the acute phase was compared before and after ablation. In the acute phase of the experiment, the incidence of VF induction decreased from 88% to 25%. In the mid-term evaluation, VF was not induced in 75% of cases. These results suggest that anatomic linear ablation along the ARVI is a promising and feasible strategy to reduce the incidence of VF induction without complications.

Academic Significance and Societal Importance of the Research Achievements

未だに大きな社会的、医学的課題である心臓突然死の主要な要因である心室細動の治療戦略に新たな選択肢が加えることができる可能性がある。

Research Products

• [Int'l Joint Research] アラバマ大学バーミングハム校(米国)
• [Journal Article] 心室細動に関する基礎知識 (2022)
  • Author(s): 飯嶋賢一
  • Journal Title: 救急医学 Volume: 46 Pages: 394-400
• [Journal Article] Right ventricular insertion promotes reinitiation of ventricular fibrillation in defibrillation failure (2021)
  • Author(s): Kenichi Iijima, Hanyu Zhang, Matthew T Strachan, Jian Huang, Gregory P Walcott, Jack M Rogers
  • Journal Title: Heart Rhythm Volume: 21 Issue: 6 Pages: 995-1003
  • DOI: 10.1016/j.hrthm.2021.01.022
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] Epicardial Linear Ablation on the Anterior Right Ventricular Insertion Suppresses the Induction of Ventricular Fibrillation. (2023)
  • Author(s): Kenichi Iijima
  • Organizer: 第40回国際心臓研究学会
  • Int'l Joint Research / Invited
• [Presentation] Epicardial Linear Ablation on the Anterior Right Ventricular Insertion Suppresses the Induction of Ventricular Fibrillation. A Proof-of-Concept Study of a Novel Anatomical Ablation Strategy for Ventricular Fibrillation. (2023)
  • Author(s): Kenichi Iijima
  • Organizer: 16th Asia Pacific Heart Rhythm Society Scientific Session
  • Int'l Joint Research
• [Presentation] A Proof of Concept Study of a Novel Anatomical Ablation Strategy for Ventricular Fibrillation. (2020)
  • Author(s): Kenichi Iijima, Daisuke Izumi, Yuki Hasegawa, Naomasa Suzuki, Takahiro Hakamata, Yasuhiro Ikami, Sou Otuki, Nobue Yagihara, Tohru Minamino
  • Organizer: 第85回日本循環器学会学術集会
  • Int'l Joint Research