Evaluation of cardiac function in fetuses of mothers with gestational diabetes.

OBJECTIVE: The purpose of this study was to assess fetal cardiac function in normal fetuses (control group) compared to those who are exposed to gestational diabetes mellitus using different echocardiographic measurements, and to explore the application of left atrial shortening fraction in determination of fetal diastolic function with gestational diabetes mellitus. METHODS: A total of 50 women with gestational diabetes and 50 women with a healthy pregnancy were included in the study. Fetal echocardiography was performed and structural as well as functional fetal cardiac parameters were measured. Data were compared between with or without fetal myocardial hypertrophy and the control group. RESULTS: In the study group, out of 50 fetuses of gestational diabetic mothers, 18 had myocardial hypertrophy and 32 had normal septal thickness. Gestational age at time of examination did not differ significantly between the control and gestational diabetes group (p = 0.55). Mitral E/A ratio was lower in gestational diabetes group as compared to the control (p < 0.001). Isovolumetric relaxation and contraction times and myocardial performance index were greater in fetuses of gestational diabetic mothers (p < 0.001). In fetuses of gestational diabetic mothers with myocardial hypertrophy, left atrial shortening fraction was lower as compared to those without myocardial hypertrophy and those of the control group (p < 0.001). CONCLUSIONS: The results of this study suggest that fetuses of gestational diabetic mothers have altered cardiac function even in the absence of septal hypertrophy, and that left atrial shortening fraction can be used as a reliable alternate parameter in the assessment of fetal diastolic function.

Three patients presenting with severe macrosomia and congenital hypertrophic cardiomyopathy: a case series.

BACKGROUND: Macrosomia and hypertrophic cardiomyopathy are two features often associated in neonates of diabetic mothers. We report the cases of three patients with severe macrosomia and critical hypertrophic cardiomyopathy without severely unbalanced maternal diabetes. Only three patients with those two features and no uncontrolled maternal diabetes have been previously reported. CASE PRESENTATION: The first patient was a 39-week-old girl, the second patient was a 39-week-old girl, and the third patient was a 41-week-old boy. The two French girls and the French boy had severe macrosomia and hypertrophic cardiomyopathy, leading to the death of the boy. The outcome of the two girls was favorable, with a standardization of growth curves and ventricular hypertrophy. Their mothers presented with high body mass index but no severe documented maternal diabetes; glycemic imbalance was only suspected on postnatal analyses. There was no hydramnios during pregnancy and no other environmental factor, especially toxic exposure. Their parents are from Mayotte, Guadeloupe, and Guinea-Conakry. The usual genetics causes, Beckwith-Wiedemann syndrome, and chromosomal copy number variation, were also excluded. CONCLUSIONS: This report suggests the implication of other factors in addition to glycemic disorders, including genetic factors, in the occurrence of macrosomia and severe hypertrophic cardiomyopathy in neonates. These three original observations indicate that gynecologists and neonatologists should pay attention to neonates from mothers with a high body mass index and when maternal diabetes is not documented.

The embryological basis of subclinical hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is caused by mutations in sarcomeric proteins, the commonest being MYBPC3 encoding myosin-binding protein C. It is characterised by left ventricular hypertrophy but there is an important pre-hypertrophic phenotype with features including crypts, abnormal mitral leaflets and trabeculae. We investigated these during mouse cardiac development using high-resolution episcopic microscopy. In embryonic hearts from wildtype, homozygous (HO) and heterozygous (HET) Mybpc3-targeted knock-out (KO) mice we show that crypts (one or two) are a normal part of wildtype development but they almost all resolve by birth. By contrast, HO and HET embryos had increased crypt presence, abnormal mitral valve formation and alterations in the compaction process. In scarce normal human embryos, crypts were sometimes present. This study shows that features of the human pre-hypertrophic HCM phenotype occur in the mouse. In an animal model we demonstrate that there is an embryological HCM phenotype. Crypts are a normal part of cardiac development but, along with the mitral valve and trabeculae, their developmental trajectory is altered by the presence of HCM truncating Mybpc3 gene mutation.

Cardiomyopathy in offspring of diabetic rats is associated with activation of the MAPK and apoptotic pathways.

BACKGROUND: Maternal diabetes affects the developing fetal cardiovascular system. Newborn offspring of diabetic mothers can have a transient cardiomyopathy. We hypothesized that cardiomyopathic remodeling is associated with activation of the mitogen activated protein kinase (MAPK) signaling and apoptotic pathways. METHODS: To evaluate the effects of moderate and severe maternal hyperglycemia, pregnant rats were made diabetic with an injection of 50 mg/kg of streptozotocin. Moderately well controlled maternal diabetes was achieved with twice daily glucose checks and insulin injections. No insulin was given to severely diabetic dams. Offspring of moderate and severe diabetic mothers (OMDM and MSDM, respectively) were studied on postnatal days 1 (NB1) and 21 (NB21). Echocardiograms were performed to evaluate left ventricular (LV) dimensions and function. Myocardial MAPK and apoptotic protein levels were measured by Western blot. RESULTS: OMDM had increased cardiac mass at NB1 compared to controls that normalized at NB21. OSDM demonstrated microsomia with relative sparing of cardiac mass and a dilated cardiomyopathy at NB1. In both models, there was a persistent increase in the HW:BW and significant activation of MAPK and apoptotic pathways at NB21. CONCLUSION: The degree of maternal hyperglycemia determines the type of cardiomyopathy seen in the offspring, while resolution of both the hypertrophic and dilated cardiomyopathies is associated with activation of MAPK signaling and apoptotic pathways.

Developmental origins of hypertrophic cardiomyopathy phenotypes: a unifying hypothesis.

The majority of genetic mutations associated with hypertrophic cardiomyopathy (HCM) occur in genes encoding sarcomeric proteins, which are expressed only in cardiomyocytes. However, some manifestations of the HCM phenotype, such as myocardial disarray, interstitial fibrosis, mitral valve abnormalities, and microvascular remodeling, indicate the involvement of other cell lineages. The link between sarcomeric gene defects and these 'extended' HCM phenotypes remains elusive. Based on novel insights provided by cardiac developmental biology, we propose that a common lineage ancestry of the diverse HCM phenotypes not involving the cardiomyocyte can be traced to the pluripotent epicardium-derived cells (EPDCs). During cardiac colonization, EPDCs differentiate into interstitial fibroblasts, coronary smooth-muscle cells, and atrioventricular endocardial cushions as mesenchymal cells. We propose that the cross-talk between healthy EPDCs and abnormally contracting cardiomyocytes might account for the diverse manifestations of HCM, by a putative mechanism of mechanotransduction leading to abnormal gene expression and differentiation.

Deletion of GSK-3beta in mice leads to hypertrophic cardiomyopathy secondary to cardiomyoblast hyperproliferation.

Based on extensive preclinical data, glycogen synthase kinase-3 (GSK-3) has been proposed to be a viable drug target for a wide variety of disease states, ranging from diabetes to bipolar disorder. Since these new drugs, which will be more powerful GSK-3 inhibitors than lithium, may potentially be given to women of childbearing potential, and since it has controversially been suggested that lithium therapy might be linked to congenital cardiac defects, we asked whether GSK-3 family members are required for normal heart development in mice. We report that terminal cardiomyocyte differentiation was substantially blunted in Gsk3b(-/-) embryoid bodies. While GSK-3alpha-deficient mice were born without a cardiac phenotype, no live-born Gsk3b(-/-) pups were recovered. The Gsk3b(-/-) embryos had a double outlet RV, ventricular septal defects, and hypertrophic myopathy, with near obliteration of the ventricular cavities. The hypertrophic myopathy was caused by cardiomyocyte hyperproliferation without hypertrophy and was associated with increased expression and nuclear localization of three regulators of proliferation - GATA4, cyclin D1, and c-Myc. These studies, which we believe are the first in mammals to examine the role of GSK-3alpha and GSK-3beta in the heart using loss-of-function approaches, implicate GSK-3beta as a central regulator of embryonic cardiomyocyte proliferation and differentiation, as well as of outflow tract development. Although controversy over the teratogenic effects of lithium remains, our studies suggest that caution should be exercised in the use of newer, more potent drugs targeting GSK-3 in women of childbearing age.

Pathologic ventricular hypertrophy in the offspring of diabetic mothers: a retrospective study.

AIMS: Diabetes in pregnant women is increasing and with that the complications in their offspring. We studied our population of diabetic mothers (2003-2005) for pathologic ventricular hypertrophy (PVH). METHODS AND RESULTS: In our retrospective study of all 87 diabetic pregnancies (92 neonates), 16 were type 1, 17 were type 2, and 54 were gestational diabetes (GD). Haemoglobin glycated (HbA1c) median was 5.8% (5.3-6.5): 17 with HbA1c above normal 2 with congenital heart disease (CHD) and six with PVH. A total of 75 neonates were normal, five had CHD, and 12 had PVH (1/12 died post-natally, 1/12 stillborn, 2/12 required premature delivery, 8/12 normal). The 16 type 1 pregnancies resulted in three neonates with CHD and in 50% PVH, including one death, one premature Cesarean section because of PVH. The 17 neonates of type 2 pregnancies showed in one CHD and in 25% PVH. Of the 54 GD pregnancies, one had CHD and one had PVH. CONCLUSION: Pregnancies of both type 1 and 2 diabetes carry an increased risk for foetal development of PVH compared with those with GD. The insufficient effect of preventive glycaemia controls leads to conclude that although no definite predictive parameters for malignant outcome can be presented, close monitoring of these pregnancies may prevent perinatal catastrophes.

Ductus venosus flow and myocardial hypertrophy in fetuses of diabetic mothers.

OBJECTIVE: To test the hypothesis that the pulsatility index of ductus venosus (PIDV) is greater in the fetuses of diabetic mothers (FDM) with myocardial hypertrophy (MH) than in the FDM with no MH and in the control fetuses of nondiabetic mothers (FNDM). Comparing the results with mitral and tricuspid diastolic peak flows. METHODS: The cross-sectional study included fetuses with gestational ages ranging from 20 weeks to term, divided into the following 3 groups: 56 FDM with MH (group I), 36 FDM with no MH (group II), and 53 FNDM (group III, control). The Doppler echocardiogram assessed the PIDV through the ratio (systolic velocity - presystolic velocity)/mean velocity. The mitral and tricuspid E and A waves were also assessed. RESULTS: The mean PIDV in groups I, II, and III were 1.13 +/- 0.64, 0.84 +/- 0.38, and 0.61 +/- 0.17, respectively. Using ANOVA and the Tukey test, a statistically significant difference was found in the 3 groups (P = 0.015 between groups I and II; P < 0.001 between groups I and III; and P = 0.017 between groups II and III). The mean mitral E wave was significantly greater in group I (0.39 +/- 0.12 m/s) than in groups II (0.32 +/- 0.08 m/s) (P = 0.024) and III (0.32 +/- 0.08 m/s) (P = 0.023). The mean tricuspid E wave was also greater in group I (0.43 +/- 0.1 m/s) than in group III (0.35 +/- 0.10 m/s) (P = 0.031). CONCLUSION: The PIDV is significantly greater in FDM with MH than in FDM with no MH and in FNDM. Because the PIDV may represent modifications in ventricular compliance, this index may be a more sensitive parameter for assessing fetal diastolic function.

Fluxo no ducto venoso e hipertrofia miocárdica em fetos de mães diabéticas / Ductus venosus flow and myocardial hypertrophy in fetuses of diabetic mothers

OBJETIVO: Testar a hipótese de que o índice de pulsatilidade do ducto venoso (IPDV) é maior nos fetos de mães diabéticas (FMD) com hipertrofia miocárdica (HM) do que em FMD sem HM e em fetos controles de mães não diabéticas (FMND) comparando os resultados com os picos de velocidade dos fluxos diastólicos nas valvas mitral e tricúspide. MÉTODOS: Estudo transversal incluindo fetos com idade gestacional entre 20 semanas até o termo, divididos em 3 grupos: 56 FMD com HM (grupo I), 36 FMD sem HM (grupo II) e 53 FMND (grupo III, controle). O Doppler-ecocardiograma avaliou o IPDV através da razão (velocidade sistólica - velocidade pré-sistólica)/velocidade média. As ondas E e A dos fluxos mitral e tricúspide foram também avaliadas. RESULTADOS: A média do IPDV no grupo I foi de 1,13 ± 0,64, no grupo II, de 0,84 ± 0,38 e no grupo III de 0,61±0,17. Aplicando-se a ANOVA e o teste de Tukey, houve diferença estatisticamente significativa entre os 3 grupos (p= 0,015 entre os grupos I e II, p < 0,001 entre os grupos I e III e p = 0,017 entre os grupos II e III). A média da onda E mitral foi significativamente maior no grupo I (0,39 ± 0,12 m/s) do que nos grupos II (0,32 ± 0,08 m/s) (p=0,024) e III (0,32 ± 0,08 m/s) (p=0,023). A média da onda E tricúspide foi também maior no grupo I (0,43 ± 0,1 m/s) do que no grupo III (0,35 ± 0,10 m/s) (p= 0,031). CONCLUSAO: O IPDV é significativamente maior em FMD com HM do que em FMD sem HM e do que em FMND. Como o IPDV pode representar modificações na complacência ventricular, este índice pode ser um parâmetro mais sensível para a avaliação da função diastólica fetal.

Embryonic gene expression in nonoverloaded ventricles of hereditary hypertrophic cardiomyopathic hamsters.

Current information regarding the molecular and biochemical mechanisms of myocardial hypertrophy, as obtained from isolated cardiomyocytes and/or healthy animals with aortic banding, does not permit dissection of the hierarchical relationship among different steps and triggers of the pathogenic process in vivo. The aim of the present study was to depict the temporal relationship among myocardial structural and functional characteristics, the embryonic gene program, and transforming growth factor (TGF) beta 1 expression in euthyroid hereditary hypertrophic cardiomyopathic hamsters (CMPH). This investigation was performed using Western and Northern blot and in situ hybridization techniques. The results show that in CMPH, the severity of the hemodynamic overload is not related to any modification in structural myocardial characteristics (cardiac mass, cardiomyocyte dimensions, total RNA, and protein content), whereas an early activation of the embryonic gene program occurs in not yet overloaded 90-day-old CMPH (left ventricular end diastolic pressure < 15 mm Hg). In these animals, a 30% to 90% decrease in the alpha myosin heavy chain (alpha MHC) relative content was found in ventricles, whereas beta MHC increased 5-fold. In addition, the alpha skeletal actin expression was enhanced 2-fold versus age-matched controls. No modifications were observed in myosin function evaluated by in vitro motility assay, whereas the administration of L-thyroxine (100 micrograms/kg intraperitoneally daily) to CMPH was able to reinduce the ventricular expression of the alpha MHC isoform (5-fold increase). Conversely, no changes were found in alpha cardiac actin and myosin light chain 2 (MLC2) expression. A close temporal relationship occurred in CMPH ventricles between the re-expression of the embryonic gene program and a 3-fold enhancement of the expression of TGF beta 1. These results indicate that the CMPH provides a useful model for investigating the expression of embryonic genes in hypertrophic ventricles in the absence of mechanical and hormonal stimuli, and that TGF beta 1 is involved in regulating in vivo the "embryonic step" of myocardial hypertrophy. Furthermore, the study offers new insights into the pathophysiologic mechanisms leading to heart failure.

[Leopard syndrome with hypertrophic obstructive cardiomyopathy and cerebral arteriovenous malformation. Report of a case]. / Síndrome de Leopard con cardiomiopatía hipertrófica obstructiva y malformación arteriovenosa cerebral. Informe de un caso.

We report a case of a 27-year-old woman with Leopard syndrome in which we observed the association of hypertrophic obstructive cardiomyopathy with arteriovenous cerebral shunt. This association has not been reported previously in the literature.