Idiopathic dilated cardiomyopathy in infant . 「小児拡張型心筋症」について Lecture on pregnancy by Dr. Mizutani,ドクター水谷のお産講座No4

 No4 lecture: Idiopathic dilated cardiomyopathy in infant

 Idiopathic dilated cardiomyopathy in infant is very difficult name to understand the disease. In brief, the heart does not work due to the damage of its muscle and then the heart does not push out the blood into the vessels. Therefore blood
circulation in the body does not work properly. Idiopathic dilated
cardiomyopathy is one of the serious heart diseases.

It is even more serious problem if this disease occurred in the baby. The heart
disease in baby means that the baby cannot live long and the whole life of the
baby will be affected by the disease. Although the etiology of this disease is
still unknown, the disease is identified after the happy birth possibly the damage
of heart muscle during fetal life. Recently as known that obstetricians are
able to monitor the fetus by 4 D echo in the uterus. However the disease is
identified after birth suggesting that fetal life is very important for this disease.
 In other words any medications during pregnancy should be considered in
relation to the possible effects on the fetal heart.

 Drugs used in pregnancy for the treatment of preeclampsia and preterm labor
are known to have toxic effects on fetal (pup’s) heart muscle. They are both
beta-2 stimulant such as terbutaline an ritodoline and magnesium sulfate.
Both drugs are known to be toxic to the pup heart.
 Last year, FDA prohibited the use of terubutaline (beta-2 stimulant) more than
 72 hours for treating preterm labor because of the risk of possible toxic effects
on maternal heart. We are concerned about the negative effects of beta-2
stimulant on fetal heart, since the drug can easily cross over placenta and reach
to the fetus.
 The needs of treatment for preeclampsia and preterm labor obliged us to use
both drugs. Without the use of both drugs we are not able to treat both
preeclampsia and preterm labor and to save the fetus. Obstetricians are in
a dilemma for saving the lives of both mother and fetus simultaneously in
this acute disease conditions.

 From 1970s obstetricians started to use intensively beta-2 stimulants and
from 1990 magnesium sulfate for the treatment of preterm labor.

For preeclampsia, the use of magnesium sulfates started much earlier.
Since both drugs easily cross over placenta and reach to the fetus,
the harmful effects of these drugs on neonatal heart cannot be
underestimated. The neonatal exposure of the drugs in uterus might have
resulted in the development of serious heart disease, namely idiopathic
dilated cardiomyopathy in infant.

 The transplantation of heart is the most effective for the treatment of
idiopathic dilated cardiomyopathy in infant. The advancement of heart
surgery including immunosuppressive drugs and environment of human
organ donor system has recently contributed to the increased number of
infant heart transplantation practices. (Fig1).

 This is good news for both mother and infants of idiopathic dilated
cardiomyopathy. However we must ask ourselves why such infants of
the case have increased recently.

 It is an urgent needs to develop an ideal drug for the treatment of
preeclampsia and preterm labor for the sake of saving the life and
health of mother and her babies .

Fig1 Number of infant heart transplantation by year by age group (world total)


International Society for Heart Transplantation registry 2011

##Hokegard KH et al. (1979) ECG –changes in the fetal lamb during asphyxia in
relation to beta-adrenoreceptor stimulation and blockade .
Acta Physiol Scand 105:195-203.

Ishii M et al.(2009) The effect of recombinant aminopeptidase A(APA) on
hypertension in pregnant spontaneously hypertensive rats(SHRs).
Early Hum Develop85:589-594.
##Mizutani S et al.(2011) A new approach regarding the treatment of
preeclampsia and preterm labor. Life Sci88:17-23.








 この報告と同じ年〈1991年〉に、体外受精で妊娠した(4胎)妊婦が妊娠18週に切迫早産症状のため、テルブタリンの皮下注射で治療を開始し、51日間のテルブタリン治療(総量200mg)の後妊娠28週で4児を帝王切開分娩(A女児1260g、B男児1270g、C男児1270g、D女児1300g )。内3児(A-C)に、生後30時間前後に心不全の症状が現れた。中でもその1児(A)には、心拍数の低下、心拍出不全、低血圧と拡張期圧の上昇、無尿が認められた。他の2例もAよりは軽症であるが同様の症状が現れた。3児ともドブタミン〈合成カテコールアミンで、ドーパミンとは異なりノルアドレナリンを増やさない〉投与で症状が改善した。ところが、D児は全く心不全の症状を示さなかった。



参考文献:T.Thorkelsson,JL Loughead. Long-term subcutaneous terubutaline Tocolysis :Report of possible neonatal toxicity. J Perinatology1991;11:235-238.





ST低下の意味、心筋の内側で(心内膜)で、 部分的に虚血(心内膜虚血)が起きている。



気管支平滑筋にある交感神経のβ2受容体刺激して、収縮していた平滑筋弛緩させ、気管支拡張する作用をもつ薬剤 喘息の発作は気管支の筋肉が痙攣〈収縮〉する状態で、β2刺激剤はその収縮を抑えます。切迫早産では、子宮の筋肉(平滑筋が収縮状態ですので、同じような考え方でβ2剤が使用されています。この薬は長期使用すると、喘息の治療薬と同様に、妊婦の心臓への負担が大きくなります。



Profesor Emeritus Robert Mittendorf, MD,DrPH, FACOG

Loyola University, Obstetric and Gynecology

Ø Wellcome to NPO Society P-LAP








文献:Mittendorf R et al. Is tocolytic magnesium sulfate associated with

increased total paediatric mortality? Lancet 1997;350:1517-1518.

In English


We are honored and delighted to inform you that Professor, Emeritus
Loyola University Chicago
Robert Mittendorf, MD, DrPH is become an Honorary Member of our NPO: Protect neonates and the mother of preterm birth and preeclampsia (gestational hypertension).

It is well-known that Dr.Robert Mittendorf has published many papers concerning to the possible negative effects on the fetus from 1997. In his paper published in Lancet 1997 he has written as follows: We are concerned that MgSO4 used in very preterm labor, mainly as a tocolytic ,may be associated with increased total pediatric mortality.


Mittendorf R et al. Is tocolytic magnesium sulfate associated with

increased total pediatric mortality? Lancet 1997;350:1517-1518.


Robert Mittendorf, MD, DrPH
Professor, Emeritus
Loyola University Chicago
Leadership Council
Harvard School of Public Health
Boston, MA






Fletcher SE. Myocardial necrosis in a newborn after long-term maternal subcutaneous terbutaline infusion for suppression of preterm labor. Am.J.Obstet&Gynecol.1991;165:1401-4.



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