日本未熟児新生児学会雑誌　第23巻　第1号　125～134頁（2011年）

日本未熟児新生児学会雑誌　23(1)：125-134；2011　

受付日：平成22．06．09

受理日：平成22．10．14

双胎間輸血症候群の新生児管理におけるTei index評価の意義―2組の一絨毛膜性双胎の生後早期心機能経過―

Myocardial Performance Index（MPI）in Twin-To-Twin Transfusion Preterm Infants

＊1現・たつの市立御津病院　小児科，＊2加古川市民病院　小児科，＊3現・神戸こども初期急病センター

＊1 Department of Pediatrics，Mitsu Municipal Hospital，＊2 Department of Pediatrics，Kakogawa Municipal Hospital，＊3 Kobe Children’s First-aid Center

村瀬真紀＊1・森沢　猛＊2・湊川　誠＊2・海老名俊亮＊2・上村裕保＊2・小林光郎＊2・小寺孝幸＊2・大西徳子＊2・岡野真理子＊2・神岡一郎＊2・石田明人＊3

Masanori MURASE＊1，Takeshi MORISAWA＊2，Makoto MINATOGAWA＊2，Syunsuke EBINA＊2， Hiroyasu UEMURA＊2，Mitsurou KOBAYASHI＊2，Takayuki KODERA＊2，Noriko OONISHI＊2， Mariko OKANO＊2，Ichiro KAMIOKA＊2，Akihito ISHIDA＊3

Key Words：TTTS，myocardial dysfunction，echocardiography，Tei index

　双胎間輸血症候群（TTTS）の新生児管理におけるTei indexの意義について，2組の一絨毛膜二羊膜性（MD）双胎の早期経時的心機能に則して考察した。MD-1（在胎27w，供血児756g，受血児1,146g）においては，受血児の生後24時間以内の左室駆出率（Left ventricular ejection fraction，以下LVEF），左室拍出量（Left ventricular output，以下LVO）は供血児より低値の傾向で，左室・右室のTei indexはパルスドプラ法（PD）においても，組織ドプラ法（TDI）においても，受血児が出生直後異常に高値で，その後低下した。MD-2（在胎27w，供血児820g，受血児1,108g）においては，受血児のLVEF，心拍補正平均左室円周短縮速度（Rate corrected mean velocity of circumferential fiber shortening，以下mVcfc）は生後12時間のみ供血児より低値で，LVOは差がなかった。左室・右室Tei indexはMD-1と同様，PD/TDIいずれも出生直後受血児のみ異常高値であり，症状の改善と共に正常化した。Tei index高値は2組とも，右室において顕著であった。Tei indexはTTTSの生後の循環管理において，従来の指標より有用である可能性が考えられた。

　We evaluated usefulness of myocardial performance index（MPI）in the postnatal management of twin-to-twin transfusion syndrome（TTTS）of monochorionic diamniotic（MD）twins. Two couples of MD twins were serially assessed for early neonatal circulation using two dimensional, M-mode, pulsed-Doppler（PD），and tissue Doppler imaging（TDI）echocardiography. First MD twins were born at 27 weeks of gestation. The donor weighed 756g and the recipient weighed 1,146g. Both values of LVEF and LVO in the recipient were lower than those in the donor before 24 hours of life. PD-MPI values in both left ventricle and right ventricle of the recipient were higher than those in the donor, and TDI-MPI values in both lateral mitral annulus and lateral tricuspid annulus of the recipient were also higher in the first two days. Second MD twins were also born at 27 weeks. The donor weighed 820g and the recipient weighed 1,108g. Both LVEF and mVcfc values were not different between infants except 12 hours of life. Both ventricular PD-MPI values in the recipient were apparently higher and both TDI-MPI values in the recipient were also higher in the first two days. Both PD-MPI and TDI-MPI values might be more useful in assessing early circulatory disturbances of TTTS than other conventional echocardiographic indices.