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Alternative methods to assess ventricular diastolic function in the fetus are proposed. Fetal myocardial hypertrophy in maternal diabetes was used as a model of decreased left ventricular compliance (LVC), and fetal respiratory movements as a model of increased LVC. Comparison of three groups of fetuses showed that, in 10 fetuses of diabetic mothers (FDM) with septal hypertrophy (SH), the mean excursion index of the septum primum (EISP) (ratio between the linear excursion of the flap valve and the left atrial diameter) was 0.36 +/- 0.09, in 8 FDM without SH it was 0.51 +/- 0.09 (P=0.001), and in the 8 normal control fetuses (NCF) it was 0.49 +/- 0.12 (P=0.003). In another study, 28 fetuses in apnea had a mean EISP of 0.39 +/- 0.05 which increased to 0.57 +/- 0.07 during respiration (P0.001). These two studies showed that the mobility of the septum primum was reduced when LVC was decreased and was increased when LVC was enhanced. Mean pulmonary vein pulsatility was higher in 14 FDM (1.83 +/- 1.21) than in 26 NCF (1.02 +/- 0.31; P=0.02). In the same fetuses, mean left atrial shortening was decreased (0.40 +/- 0.11) in relation to NCF (0.51 +/- 0.09; P=0.011). These results suggest that FDM may have a higher preload than normal controls, probably as a result of increased myocardial mass and LV hypertrophy. Prenatal assessment of LV diastolic function by fetal echocardiography should include analysis of septum primum mobility, pulmonary vein pulsatility, and left atrial shortening.

To test the hypothesis that a correlation exists between the maximum foramen ovale diastolic diameter and the excursion index (EI) of the septum primum in normal fetuses.One hundred and two normal fetuses with gestational ages ranging from 20 to 40 weeks were submitted to echocardiography. The foramen ovale diameter and the "maximal excursion" of the septum primum were measured in a 4-chamber view. The data were analyzed by Pearson's correlation coefficient.The mean foramen ovale (FO) diameter was 5.06 +/- 1.29 mm; the maximal excursion of the septum primum was 5.42 +/- 1.41 mm; the left atrium diameter 11.47 +/- 2.76 mm; the septum primum "excursion index" was 0.48 +/- 0.09. Mean FO/EI ratio was 11.35 +/- 3.94 mm. No FO/EI correlation (r = -0.03) existed, and a weak foramen ovale/left atrium correlation (r = 0.31) was observed, as well as a weak foramen ovale/excursion of septum primum correlation (r = 0.21).Septum primum mobility does not depend on the foramen ovale diameter in normal fetuses, suggesting that the modifications of its diastolic displacement is not influenced by the size of the interatrial opening.

OBJETIVO: Testar a hipótese de que existe correlação entre o diâmetro máximo diastólico do forame oval e o índice de excursão do septum primum em fetos normais. MÉTODOS: Foram examinados, por ecocardiografia, 102 fetos normais de gestantes com idades gestacionais entre 20 e 40 semanas. O diâmetro do forame oval e a excursão máxima do septum primum foram medidos num corte de 4 câmaras. Na análise dos dados utilizou-se o coeficiente de correlação de Pearson. RESULTADOS: A média do forame oval foi de 5,06 ± 1,29 mm; a da excursão máxima do septum primum de 5,42 ± 1,41 mm; a do átrio esquerdo 11,47 ± 2,76 mm e a do índice de excursão 0,48 ± 0,09. A relação média FO/IE foi de 11,35 ± 3,94 mm. Não houve correlação FO/IE (r = -0,03) e observou-se correlação fraca do forame oval com o átrio esquerdo (r = 0,031) e com a excursão do septum primum (r = 0,21). CONCLUSÃO: A mobilidade do septum primum não depende do diâmetro do forame oval em fetos normais, sugerindo que as modificações da sua excursão diastólica não decorram do grau de abertura interatrial. OBJECTIVE: To test the hypothesis that a correlation exists between the maximum foramen ovale diastolic diameter and the excursion index (EI) of the septum primum in normal fetuses. METHODS: One hundred and two normal fetuses with gestational ages ranging from 20 to 40 weeks were submitted to echocardiography. The foramen ovale diameter and the "maximal excursion" of the septum primum were measured in a 4-chamber view. The data were analyzed by Pearson's correlation coefficient. RESULTS: The mean foramen ovale (FO) diameter was 5.06 ± 1.29 mm; the maximal excursion of the septum primum was 5.42 ± 1.41 mm; the left atrium diameter 11.47 ± 2.76 mm; the septum primum "excursion index" was 0.48 ± 0.09. Mean FO/EI ratio was 11.35 ± 3.94 mm. No FO/EI correlation (r = -0.03) existed, and a weak foramen ovale/left atrium correlation (r = 0.31) was observed, as well as a weak foramen ovale/excursion of septum primum correlation (r = 0.21). CONCLUSION: Septum primum mobility does not depend on the foramen ovale diameter in normal fetuses, suggesting that the modifications of its diastolic displacement is not influenced by the size of the interatrial opening.

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.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.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; P0.001 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).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.

OBJETIVO: Testar a hipótese de que a fração de encurtamento atrial esquerda seja menor nos fetos de mães diabéticas do que em fetos de mães sem doenças sistêmicas. MÉTODOS: Foram examinados, por ecocardiografia, 42 fetos de mães com diabetes prévio ou gestacional e 39 fetos normais de mães sem doença sistêmica (controles), com idades gestacionais a partir da 25ª semana até o termo. A fração de encurtamento atrial esquerda foi obtida pelo quociente diâmetro máximo do átrio esquerdo (AE) - diâmetro mínimo AE/diâmetro máximo AE. Os dados foram comparados pelo teste t de Student, com um alfa crítico de 0,05. RESULTADOS: Os filhos de mães diabéticas apresentaram fração de encurtamento atrial esquerda média de 0,39 ± 0,15 e os fetos do grupo controle de 0,51 ± 0,11. Esta diferença foi significativa, com p < 0,001. CONCLUSÃO: A dinâmica atrial esquerda, com diminuição do seu encurtamento global, está acentuada nos filhos de mães diabéticas. Especulamos que este parâmetro possa ser útil na avaliação da função diastólica ventricular esquerda fetal. OBJECTIVE: To test the hypothesis that left atrial shortening fraction is lower in fetuses of diabetic mothers than in fetuses of mothers with no systemic disease. METHODS: Forty-two fetuses of mothers with previous diabetes or gestational diabetes and 39 healthy fetuses of mothers with no systemic disease (controls) underwent echocardiographic examination. Their gestational ages ranged from 25 weeks to term. The left atrial shortening fraction was obtained with the following formula: (left atrial maximum diameter - left atrial minimum diameter)/left atrial maximum diameter. Data were compared using the Student t test, with an alpha level of 0.05. RESULTS: Mean left atrial shortening fractions in fetuses of diabetic mothers and in those in the control group were 0.39±0.15 and 0.51±0.11, respectively. This difference was significant with P < 0.001. CONCLUSION: Left atrial dynamics, with a reduction in global left atrial shortening, is increased in fetuses of diabetic mothers. We speculate that this parameter may be useful in assessing fetal left ventricular diastolic function.

OBJECTIVE: To verify the hypothesis that the pulmonary vein pulsatility index is higher in fetuses of diabetic mothers than it is in normal fetuses of nondiabetic mothers. METHODS: Twenty-four fetuses of mothers with either gestational or previous diabetes (cases), and 25 normal fetuses of mothers without systemic disease (control) were examined. Fetuses were examined through prenatal Doppler and color flow mapping. The pulmonary vein pulsatility index was obtained by placing the pulsed Doppler sample volume over the right superior pulmonary vein and applying the formula (systolic velocity - presystolic velocity)/mean velocity. RESULTS: The mean gestational age of the study fetuses was 30.3±2.7 weeks, and gestational age of the controls was 29±3.3 weeks, with no significant difference in gestational age between groups (p=0.14). Fetuses of diabetic mothers had a mean pulmonary vein pulsatility index of 1.6±1, and those of the control group had an index of 0.86±0.27. CONCLUSION: Fetuses of diabetic mothers had pulmonary vein pulsatility indexes (parameter easily obtained through Doppler echocardiography that may be related to fetal diastolic function) higher than those in fetuses of mothers with normal glycemia.