心臓幹細胞は心不全治療に役立つ可能性がある（LBCT-20230）

心臓幹細胞は虚血性心筋症患者において生存可能な心筋、LV収縮能、および機能的能力を
増大させる可能性がある
SCOPIO: Cardiac stem cells increase viable myocardium, LV systolic function, and functional capacity in patients with ischemic cardiomyopathy
術中に患者自身の心臓から心臓幹細胞を分離し後により多数の細胞を再注入することにより、将来心筋梗塞後LV機能不全患者を治療できる可能性があると2012年American Heart Association学会で発表された。Effect of Cardiac Stem Cells In Patients with Ischemic CardiOmyopathy（SCIPIO）トライアルにおいて研究者らは、冠動脈バイパス術を施行された心不全患者33人において心臓組織小片を採取し、c-kit CSCsと呼ばれる心臓幹細胞を分離した。その後彼等はさらに細胞を増殖させ治療に割り当てられた患者20人に注射した。治療を受けた患者20人においてLVEFは4か月後にはCSC注射前の29.0± 1.7%から36.0 ± 2.5%に増加し(P <0.001)、1年後には8.1%増加し続け、2年後には最大12.9%増加した（8人）。治療を受けた患者の瘢痕化した心筋部位の収縮能は4か月後には7.6%改善し、2年後には18.4%増加した。治療を受け心筋核磁気共鳴画像検査を施行された9人の患者において梗塞サイズは有意に減少し、CSCs前には34.9gであったものが4か月後に21.6gとなり、1年後には18.7gとなった。治療を受けなかったコントロール13人においては、1年後の時点で有意な変化はなかった。
Full Text

Cardiac stem cells may one day be an effective treatment for heart failure caused by muscle scarring after a myocardial infarction, according to late-breaking clinical trial results presented at the American Heart Association's Scientific Sessions 2012.

In the Effect of Cardiac Stem Cells In Patients with Ischemic CardiOmyopathy (SCIPIO) trial, heart function and quality of life improved in 20 people treated with their own cardiac stem cells (CSCs).

"This is exciting," said Roberto Bolli, M.D., lead author of the trial, chief of Cardiovascular Medicine and director of the Institute of Molecular Cardiology at the University of Louisville in Kentucky. "The effect of these cells has continued for up to two years, and has gotten stronger. There was also a major reduction in heart scarring."

In 33 patients with heart failure who had undergone coronary artery bypass surgery, researchers removed a tiny piece of heart tissue and isolated heart stem cells called c-kit CSCs. Researchers then grew additional cells to infuse into 20 volunteers assigned to treatment.

Among outcomes found two years after treatment:

  • The 13 untreated control patients had no meaningful improvement in their hearts' pumping ability, contraction of the damaged wall of the heart or quality of life at 1 year.
  • The LVEF on the 20 treated patients increased from 29.0± 1.7% before CSC infusion to 36.0 ± 2.5% 4 months later (P <0.001) and continued to increase 8.1 percent at one year and, for the eight patients who were followed longer, 12.9 percent at two years.
  • Contracting ability of the scarred part of the heart in treated patients improved 7.6 percent at four months, 7 percent at one year and 18.4 percent at two years.
  • Heart muscle scarring in nine treated patients who underwent cardiac magnetic resonance reduced significantly, from 34.9 grams before CSCs to 21.6 grams at four months and 18.7 grams at one year. Viable heart muscle increased by 11.6 grams at four months and 31.5 grams at one year.
  • Quality of life, measured using an inverse scoring system, improved in the treatment group from 44.1 before CSCs to 25.1 at four months, 19.9 at one year and 22.8 at two years.

"We have not seen any deaths among the patients, or any adverse effects that can be ascribed to the stem cells," Bolli said.

Larger, multi-center studies are needed to confirm the findings, Bolli said.

The Jewish Hospital, University of Louisville, and the National Institutes of Health funded the study. Co-authors' names are on the abstract.