Isovolumetric Contraction Time Research Articles

Echocardiographic Detection of Subclinical Left Ventricular Dysfunction in Asymptomatic Type Two Diabetes Mellitus

Background: Before systolic dysfunction and symptomatic heart, diabetic cardiomyopathy begins with left ventricular diastolic dysfunction (LVDD). Echocardiographic modalities were used to detect subclinical LV impairment in asymptomatic type 2 diabetics. This study aimed to identify subclinical left ventricular impairment in asymptomatic patients with type two diabetes using several echocardiographic techniques. Methods: In the present prospective cohort study, 30 adults over 18 having type II diabetes mellitus (DM) (Group I) and 20 normal controls (Group II) were studied. Transthoracic echocardiography and 12-lead ECG were performed on all individuals. Results: Pulsed wave Doppler techniques revealed significant variation in transmitral flow velocities between groups, including septal e', lateral mitral annulus early velocity (e'), septal early diastolic peak flow velocity (E)\e', Lateral E\e', and average E\e'. EF was significantly decreased in group I (P < 0.001). With a p-value of 0.001, LVESD was significantly higher in group I. The septal, lateral, and average systolic mitral annulus (S') motions in group II were significantly larger than those in group I. When comparing groups, I and II, the first showed much longer myocardial performance index (MPI) and isovolumetric contraction time (IVCT). The ET for Group I was significantly lower than that of Group II. The study group exhibited significantly greater levels of fasting blood sugar, post-prandial blood sugar, and haemoglobin A1C (HBA1C) compared to the control group (P <0.001). Conclusions: Patients having diabetes mellitus exhibited considerably greater levels of DM history fasting glucose levels, postprandial glucose levels, haemoglobin A1C (HBA1C), E/e´ ratio, LVESD, IVCT, and MPI, while having significantly lower EF and ET relative to the healthy group.

Serial tissue Doppler imaging in the evaluation of bronchopulmonary dysplasia-associated pulmonary hypertension among extremely preterm infants: a prospective observational study.

To evaluate serial tissue Doppler cardiac imaging (TDI) in the evolution of bronchopulmonary dysplasia-associated pulmonary hypertension (BPD-PH) among extremely preterm infants. Prospective observational study. Single-center, tertiary-level neonatal intensive care unit. Infant born <28 weeks gestation. Utility of TDI in the early diagnosis and prediction of BPD-PH and optimal timing for screening of BPD-PH. A total of 79 infants were included. Of them, 17 (23%) had BPD-PH. The mean gestational age was 25.9 ± 1.1 weeks, and mean birth weight was 830 ± 174 g. The BPD-PH group had a high incidence of hemodynamically significant patent ductus arteriosus (83% vs. 56%, p < 0.018), longer oxygen days (96.16 ± 68.09 vs. 59.35 ± 52.1, p < 0.008), and prolonged hospital stay (133.8 ± 45.9 vs. 106.5 ± 37.9 days, p < 0.005). The left ventricular eccentricity index (0.99 ± 0.1 vs. 1.1 ± 0.7, p < 0.01) and the ratio of acceleration time to right ventricular ejection time showed a statistically significant trend from 33 weeks (0.24 ± 0.05 vs. 0.28 ± 0.05, p < 0.05). At 33 weeks, the BPD-PH group showed prolonged isovolumetric contraction time (27.84 ± 5.5 vs. 22.77 ± 4, p < 0.001), prolonged isovolumetric relaxation time (40.3 ± 7.1 vs. 34.9 ± 5.3, p < 0.003), and abnormal myocardial performance index (0.39 ± 0.05 vs. 0.32 ± 0.03, p < 0.001). These differences persisted at 36 weeks after conceptional gestational age. TDI parameters are sensitive in the early evolution of BPD-PH. Diagnostic accuracy can be increased by combining the TDI parameters with conventional echocardiographic parameters. BPD-PH can be recognizable as early as 33-34 weeks of gestation.

A new Doppler index, cerebro-placental-uterine ratio, and fetal cardiac parameters in early onset preeclampsia.

Our aim was to investigate the significance of cerebro-placento-uterine ratio CPUR, a new Doppler index, and fetal cardiac parameters (Mod MPI, EFT) in early-onset preeclampsia (EOPE) and to examine whether these parameters are related to perinatal outcome. Forty participants diagnosed with EOPE (preeclampsia cases diagnosed before 34 weeks of gestation) and 40 healthy pregnant women were included in this study. Demographic data were recorded. Doppler parameters such as middle cerebral artery (MCA), umbilical artery (UA), and uterine artery (Ut-A), and left modified myocardial performance index (Mod-MPI) and epicardial fat thickness (EFT) were measured. Cerebroplacental ratio (CPR) was determined by dividing MCA pulsatility index (PI) by UA PI. CPUR was calculated as the ratio of CPR to mean UtA-PI (CPUR = CPR/UtA-PI). All parameters were compared between the EOPE and control groups. Correlation tests were used to examine the relationship between Doppler parameters and perinatal outcome. p values less than 0.05 were considered statistically significant. The pulsatility index of the middle cerebellar artery, CPUR and CPR values were statistically lower in the EOPE group than in the control group (p = 0.002; p = <0.001; p = <0.001; respectively). No statistical differences were found between groups for isovolumetric contraction time (ICT), isovolumetric relaxation time (IRT), ejection time (ET), left mod-MPI, EFT (p = 0.117; p = 0.093; p = 0.398; p = 0.882; p = 0.202, respectively). Umbilical artery Doppler pulsatility index (PI), mean uterine artery Doppler pulsatility index (PI), were higher in the EOPE group than in the control group (p = 0.006; and p = <0.001, respectively). The CPUR value for predicting EOPE was ≤1.3652 with 74. 4% sensitivity and 94.9% specificity. Positive correlations were found between CPUR, CPR, and some neonatal parameters. CPUR, a new index combining fetal and uterine Doppler indices, may add contribution to predict adverse perinatal outcome and EOPE.

Assessment of fetal cardiac functions in pregnant women with anemia: prospective, case-control study.

To compare the fetal cardiac functions between pregnant women with iron deficiency anemia (IDA) and healthy controls. This single-center, prospective, case-control study was conducted at a tertiary hospital. A total of 150 patients, including 50 patients with IDA and 100 healthy pregnant women at 30-34 weeks of gestation, were included in the study. Of the patients with anemia, 20 had mild anemia, 18 had moderate anemia, and 12 had severe anemia. Pulsed-wave Doppler, M-mode, and tissue Doppler imaging (TDI) were performed to evaluate fetal cardiac functions. The fetal cardiac score was calculated using the systolic, diastolic, and global hemodynamic function parameters. The myocardial performance index and isovolumetric relaxation time were significantly higher in the IDA group than the control group, while isovolumetric contraction time was similar. Among the tricuspid and mitral valve diastolic parameters, the E, A, and E/A values were significantly lower in the IDA group (p<0.001). Mitral and tricuspid annular plane systolic excursions (MAPSE and TAPSE, respectively) were significantly lower in the IDA group (p<0.001). The IDA group also had significantly lower values for the TDI parameters, mitral and tricuspid E', A', S', E'/A' and a significantly higher E/E' ratio (p<0.001). Upon examination of anemia subgroups, a significant decrease was observed in the tricuspid and mitral A, E, and E/A in those with severe anemia (p<0.001). M-mode Doppler analysis revealed significantly lower TAPSE and MAPSE in the patient group with severe anemia. According to the subgroup comparison of TDI findings, the patients with severe anemia had significantly lower tricuspid and mitral E', A', S' and E'/A' (p<0.001) values and a significantly higher E/E' ratio (p<0.001). The fetal cardiac score was significantly higher in the maternal IDA group compared to the control group. A significant negative correlation was found between maternal hemoglobin level and fetal cardiac score (p<0.001). There may be changes in the systolic and diastolic cardiac functions of the fetuses of pregnant women with IDA. This study showed an increased E/E' ratio in the fetuses of pregnant women with IDA, suggesting a decrease in fetal heart maturation. Within the IDA group, fetal cardiac functions were more affected in those with severe anemia. This article is protected by copyright. All rights reserved.

Assessment of fetal cardiac function in early fetal life: feasibility, reproducibility, and early fetal nomograms

BackgroundFetal cardiology has shown a rapid development in the last decades. Fetal echocardiography is not only used for the detection of structural anomalies but also to assess fetal cardiac function. Assessment of the fetal cardiac function is performed mostly at second and third trimester. The study of fetal cardiac function at the end of first timester has not been properly investigated and there is a lack of reference values at early gestational weeks. ObjectiveTo assess whether the measurement of time related parameters of cardiac function in the left ventricle of the fetal heart is feasible and reproducible at the end of the first trimester. If possible, we provide nomograms of these parameters from 11 to 13.6 gestational weeks. Study designWe conducted a prospective observational study from March to September 2022. The study was carried out in two hospitals (Hospital Universitari Dexeus, Barcelona and Hospital VITAHS 9 Octubre, Valencia). The scans were performed by 3 specialists in fetal medicine. Exclusion criteria were: fetal cardiac rhythm abnormalities, abnormal nuchal translucency, abnormal ductus venosus, fetal malformations, stillbirth, estimated fetal weight< 10 centile, diabetes and gestational hypertensive disorders. The cardiac function parameters studied in the left ventricle were: isovolumetric contraction time, isovolumetric relaxation time, ejection time, filling time, cycle time, myocardial performance index, ejection time fraction and filling time fraction. We study the feasibility and intra- and inter-observer reproducibility of this parameters using the interclass correlation coefficient (ICC). Nomograms were made and the percentiles of the values of the different parameters were calculated. Results409 cases were recruited but only 296 could be included in the statistical analysis once exclusion criteria were applied. The intra-observer reproducibility study was excellent (ICC>0.900) and the inter-observer reproducibility study was good (ICC>0.700). Data regression analysis showed that cycle time, filling time, isovolumetric contraction time and filling time fraction increased with gestational age, whereas ejection time fraction decreased with gestational age and myocardial performance index (mean 0.43±0.08), isovolumetric relaxation time (mean 0.04±0.01) and ejection time (mean 0.16±0.01) remained constant from 11 to 13 weeks. ConclusionsThe study of fetal cardiac function is feasible and reproducible at 11 to 13+6 gestational weeks. Nomograms of the studied parameters are provided.

The effect of iron deficiency anemia on myocardial function in pediatrics

BackgroundIron deficiency is one of the most common types of anemia in children. Anemia leads to tissue hypoxia, which activates compensatory mechanisms such as increased cardiac output. Tissue Doppler imaging (TDI) is a useful echocardiographic technique for evaluation of regional and global myocardial systolic and diastolic function. ObjectivesThis study aimed to determine whether iron deficiency anemia (IDA) affects myocardial function in pediatric patients using conventional echocardiography and TDI. MethodsThis case-control study was conducted at an outpatient general pediatric clinic in cooperation with the Cardiology Unit of the Pediatric Department of Fayoum University Hospital from May 2021 to February 2022. The study included 30 cases with IDA and 30 apparently healthy children. The two study groups were matched for age and sex. ResultsThere was an increase in left ventricular end-diastolic diameter (LVEDD), while the control group showed increased ejection time (ET). There was a statistically significant lower mean E/A ratio among cases. There was a positive correlation between serum iron levels, ET, and isovolumetric contraction time (IVCT) among the cases. Additionally, there was a negative correlation between hemoglobin levels and LVEDD in the entire study group. No significant difference was found between the two study groups regarding the Tei index. ConclusionMinimal alterations in LV function parameters may occur due to IDA. A decrease in serum iron levels was significantly associated with further decreases in ET and IVCT. Additionally, there was a statistically significant lower mean E/A ratio among cases.

Feasibility study on evaluating right ventricular diastolic function by new Tei’-Index

ObjectiveDoppler-derived myocardial performance index (Tei) has been used in the evaluation of right ventricular (RV) function. However, the usage in isolated diastolic dysfunction is limited.We sought to find a new Tei’-index that is more appropriate for evaluating isolated diastolic dysfunction (IDD) based on the symmetry of cardiac structure and function. Methods21 patients with impaired RV relaxation were compared to 44 control subjects. Tei and Tei’ including their components, isovolumetric relaxation time (IRT), isovolumetric contraction time (ICT), the ejection time (ET), and RV rapid filling time (RFT) were measured from RV outflow and tricuspid inflow Doppler velocity profiles. ResultsTei-index have no change between IDD group and control subjects (0.21 ± 0.08 vs 0.23 ± 0.07 PNS). The Tei’-index was significantly shortened in IDD group(0.24 ± 0.09 vs 0.32 ± 0.12,p＜0.05).The decrease in Tei’-index was due to the prolongation of both IRT and RFT, and in the abbreviation of ICT. Tei’-index cutoff value of ≥0.31 identified impaired RV relaxation with a sensitivity of 50 % and specificity of 86 %.We also find that the Tei’-index correlated well with doppler measures of diastolic parameters like E/A, E/e’, DT, which suggests its potential use as a noninvasive indicator of the right ventricular (RV) relaxation in patients with heart failure of different causes. ConclusionNew Tei's index is highly effective and specific in the evaluation of early diastolic dysfunction of right ventricle, and can be used as an indicator for the detection of IDD in clinic.

The Importance of Tissue Doppler Imaging and M-Mode Ultrasonography in Fetuses With Preterm Premature Rupture of Membranes: A Case-Control Study.

To compare the cardiac functions of fetuses with preterm premature rupture of membranes (PPROM) between their control groups and investigate its relationship with perinatal outcomes. This prospective study was conducted with 102 pregnant women. Pregnant women with PPROM were divided into two subgroups Group A, between 26 and 30 weeks, and Group B, between 30 and 34 weeks. A control group was formed by randomly including one healthy pregnant woman for each study patient. Sociodemographic, obstetric data, tissue Doppler imaging, and M-mode imaging results were compared. The relationship between echocardiographic parameters and perinatal outcomes was also investigated. Tricuspid annular plane systolic excursion (TAPSE), S', and ET' of systolic cardiac parameters were shortened in both groups compared with their controls. Diastolic function indicator E'/A', and global function indicator myocardial performance index' increased in both groups. Isovolumetric contraction time' did not change between groups. A correlation was found between myocardial performance index', and the length of neonatal intensive care unit stay in Group A and TAPSE and duration of respiratory support and length of neonatal intensive care unit stay in Group B. The fetal cardiac function seems to be affected by PPROM, and these changes are associated with neonatal outcomes. Therefore, administering fetal cardiac function evaluation in pregnancies complicated by PPROM may help physicians establish more appropriate clinical management protocols in this special population.

Evaluation of fetal myocardial performance index in gestational diabetes mellitus.

This study aimed to compare fetal myocardial performance index (MPI) between fetuses of pregnant women with gestational diabetes mellitus (GDM) and healthy controls and to evaluate the relationship between MPI and maternal glucose levels. This was a prospective study of 90 pregnant women, including 50 pregnancies with GDM (27 pregnancies with insulin-regulated GDM and 23 pregnancies with diet-regulated GDM) and 40 healthy controls. Isovolumetric contraction time (ICT) + isovolumetric relaxation time (IRT)/ejection time (ET) were used to calculate the MPI (MPI = [ICT + IRT]/ET). Fetal MPI, PR interval, E/A ratio, maternal plasma glucose levels on the day of MPI measurement, and neonatal outcomes were compared. The fetal left-MPI was significantly higher in the GDM group than healthy controls (0.43 ± 0.04 vs. 0.40 ± 0.06, p = 0.007). The best cut-off level for MPI was >0.41 to predict adverse perinatal outcomes (sensitivity: 70%, specificity: 68%, area under the curve: 0.715, 95% confidence interval: 0.5143-0.8205, p < 0.001). The fetal MPI values showed no correlation with maternal plasma fasting, postprandial glucose, and hemoglobin A1c (HbA1c) levels. Reduced E/A ratio, higher neonatal intensive care unit admissions, and the need for cesarean delivery were detected in the GDM group. Fetal MPI is impaired in women with GDM, and the need for insulin therapy is associated with higher MPI values and adverse neonatal outcomes. Fetal MPI can help detect fetuses with potential adverse outcome risks, owing to impaired fetal cardiac function.

Effect of glycemic control on fetal hearts of pregestational diabetic women by tissue doppler and M-mode imaging.

To determine whether changes in fetal heart function according to glycemic control in pregnant women with Type 1 and Type 2 diabetes using spectral tissue Doppler imaging (TDI) and M-mode imaging. This study included 68 pregestational diabetic women (DM) at 30-32 gestational weeks. All participants were divided into two groups: type 1(n=17) and type 2(n=51), and then these groups were divided into the subgroups as well-controlled and poorly controlled, according to fasting glucose (FG) and 1-h postprandial glucose (PPG) values. Cardiac parameters were compared for well- and poorly-controlled groups with TDI and M-mode imaging. The correlation of cardiac parameters with FG, PPG, and HbA1c values was evaluated. Their roles in predicting neonatal outcomes were also assessed. Thickness measurements, early diastolic annular peak velocity (E'), late diastolic annular peak velocity (A'), tissue isovolumetric relaxation time (IRT'), and tissue myocardial performance index (MPI') were increased in both poorly controlled groups. Tissue ejection time (ET') was significantly reduced in the poorly controlled groups, while tissue isovolumetric contraction time (ICT') was not significantly changed in any group. Tricuspid, mitral, and septal annular plane excursions (TAPSE, MAPSE, and SAPSE, respectively) were significantly decreased in all poorly controlled subgroups. E', E'/A', MPI', IRT', ET', and M-mode imaging parameters significantly correlated with FG notably. Maternal hyperglycemia leads to subtle changes in systolic and diastolic functions both in the interventricular septum and ventricles, so it is essential to ensure glycemic control in both Type 1 and Type 2 DM.

Evaluation of Fetal Cardiac Output and Modified Myocardial Performance Index in Pregnant Women with Idiopathic Polyhydramnios: A Case Control Study from a Tertiary Hospital.

This study aimed to investigate fetal cardiac output and myocardial performance index in pregnant women with idiopathic polyhydramnios and compare them to healthy pregnant women. Thirty patients admitted to Ankara City Hospital at 24-39 weeks of gestation with idiopathic polyhydramnios were included as the study group. Clinical characteristics, fetal cardiac output, and fetal modified myocardial performance index (Mod-MPI) were compared between the groups. The combined cardiac output (CCO), left cardiac output (LCO), right cardiac output (RCO), pulmonary artery velocity time integral (PA-VTI), and aortic VTI were statistically significantly higher in the study group (p=0.003, p=0.028, p=0.002, p=0.000, and p=0.017, respectively).The idiopathic polyhydramnios group had a significantly higher Mod-MPI and isovolumetric contraction time (ICT) and a significantly lower ejection time (ET) compared to the controls (p=000, p=0.003, and p=0.023, respectively). In the idiopathic polyhydramnios group, the aortic max (p=0.009) and aortic VTI (p=0.047) values were significantly lower and the left ventricular outflow tract isovolumetric relaxation time (LVOT-IRT) (p=0.021) was significantly higher in cases where the NICU was required. According to the ROC analysis performed in the idiopathic polyhydramnios group, the optimal cut-off values of aortic max, aortic VTI, and LVOT-IRT in the prediction of the NICU requirement were (57.5, 0.089 and 41.5, respective cut-off value) (p=0.010, p=0.048, p=0.021, respectively). Both fetal cardiac output and Mod-MPI values were altered in fetuses with idiopathic polyhydramnios.

Impact of overweight and obesity in the fetal cardiac function parameters in the second and third trimesters of pregnancy.

To assess the impact of overweight and obesity in the second and third trimesters of pregnancy on fetal cardiac function parameters. We performed a prospective cohort study of 374 singleton pregnant women between 20w0d and 36w6d divided into three groups: 154 controls (body mass index - BMI < 25 kg/m2), 140 overweight (BMI 25-30 kg/m2) and 80 obese (BMI ≥ 30 kg/m2). Fetal left ventricular (LV) modified myocardial performance index (Mod-MPI) was calculated according to the following formula: (isovolumetric contraction time + isovolumetric relaxation time)/ejection time. Spectral tissue Doppler was used to determine LV and right ventricular (RV) myocardial performance index (MPI'), peak myocardial velocity during systole (S'), early diastole (E'), and late diastole (A'). We found significant differences between the groups in maternal age (p < 0.001), maternal weight (p < 0.001), BMI (p < 0.001), number of pregnancies (p < 0.001), parity (p < 0.001), gestational age (p = 0.013), and estimated fetal weight (p = 0.003). Overweight pregnant women had higher LV Mod-MPI (0.046 versus 0.044 seconds, p = 0.009) and LV MPI' (0.50 versus 0.47 seconds, p < 0.001) than the control group. Obese pregnant women had higher RV E' than control (6.82 versus 6.33 cm/sec, p = 0.008) and overweight (6.82 versus 6.46 cm/sec, p = 0.047) groups. There were no differences in 5-min APGAR score < 7, neonatal intensive care unit admission, hypoglycemia and hyperglobulinemia between the groups. We observed fetal myocardial dysfunction in overweight and obese pregnant women with higher LV Mod-MPI, LV MPI' and RV E' compared to fetuses from normal weight pregnant women.

Evaluation of the fetal myocardial performance ındex and Epicardial fat thickness in pregnant women with preterm prelabor rupture of membranes

Objective To assess the epicardial fat thickness (EFT) and modified myocardial performance index (Mod-MPI) measurements in fetuses at pregnant women with preterm prelabor rupture of membranes (pPROM) and compare them to healthy pregnant women’s fetuses. Methods Forty patients who presented to our clinic at 24–36 + 6 gestational weeks and were diagnosed with pPROM were included in the patient group. During the same period, 40 healthy pregnant women at similar gestational weeks were randomly selected as the control group. Results The pPROM and control groups were similar in terms of demographics. In the pPROM group, EFT, Mod-MPI, and isovolumetric contraction(ICT) and relaxation times(IRT) were significantly higher and ejection time (ET) was significantly lower compared to the control group. In addition, Mod-MPI z-scores, IRT z-scores, ICT z-scores were significantly higher and ET z-scores was significantly lower in the pPROM. According to the ROC analysis, the optimal cutoff value of EFT was calculated as 1.55 mm, with 68% sensitivity and 71% specificity (AUC: 0.718, 95% CI: 0.550–0.786, p = .018) for predicting NICU requirement and the optimal cutoff value of EFT was calculated as 1.55 mm with 72% sensitivity and 73% specificity (AUC: 0.726, 95% CI: 0.556–0.896, p = .015) for predicting medication use in the pPROM group. Conclusion This study revealed differences in the EFT and Mod-MPI measurements of the fetuses of pregnant women with pPROM. Considering that EFT is an important energy source for the myocardium, as well as an endocrine structure in which inflammatory and anti-inflammatory markers are secreted, it is recommended to be evaluated in inflammatory conditions such as pPROM.

Down syndrome patients with normal hearts: are they really normal?

Even though congenital heart disease is a common finding in down syndrome (DS) patients, some of them have anatomically normal hearts. However, the term "normal" might not be suitable, as these patients usually suffer from functional cardiac dysfunction. Several research highlighted that despite the absence of anatomical heart defects, subtle cardiac function derangements are present in DS patients. We aim to assess cardiac functions by Two-dimensional echocardiography and tissue Doppler imaging (TDI) in pediatric DS patients who have anatomically normal hearts. One hundred seventy-two patients with karyotyping confirmed DS with anatomically normal hearts and 165 healthy normal control children were enrolled in the current study. Their cardiac functions were assessed using both 2-dimensional echocardiography and TDI. Both patients and controls had structurally and anatomically normal hearts. In DS patients, the right side of the heart showed a significant reduction in both systolic and diastolic functions. Systolic dysfunction was evident by significantly decreased levels of Tricuspid annular plane systolic excursion and systolic wave by TDI. Diastolic dysfunction of the right ventricle was evident by prolonged deceleration time by conventional echocardiography and a significant decrease in annular tissue doppler velocity during early diastole/late diastole ratio by TDI. The E/De ratio was significantly increased. Even with anatomically normal hearts, DS patients should undergo cardiac function assessment by echocardiography & TDI. TDI is superior to conventional echocardiography in detecting subtle cardiac dysfunction especially left ventricular diastolic dysfunction in DS patients. TDI showed a significant decrease in the early/atrial ratio of mitral valve annulus and prolongation of left ventricle isometric relaxation time in DS children. Also, the left ventricle E/De ratio was prolonged denoting elevated filling pressures and diastolic dysfunction. This indicates that the TDI has higher sensitivity to detect diastolic dysfunction than conventional Echocardiography. Biventricular TDI-derived myocardial performance index was found to be significantly increased in DS children.

Comparisons of serum non-transferrin-bound iron levels and fetal cardiac function between fetuses affected with hemoglobin Bart's disease and normal fetuses.

To compare the levels of Non-transferrin bound iron (NTBI) in fetuses with anemia, using Hb Bart's disease as a study model, and those in unaffected fetuses and to determine the association between fetal cardiac function and the levels of NTBI. A prospective study was conducted on pregnancies at risk of fetal Hb Bart's disease. All fetuses underwent standard ultrasound examination at 18-22 weeks of gestation for fetal biometry, anomaly screening and fetal cardiac function. After that, 2 ml of fetal blood was taken by cordocentesis to measure NTBI by Labile Plasma Iron (LPI), serum iron, hemoglobin and hematocrit. The NTBI levels of both groups were compared and the correlation between NTBI and fetal cardiac function was determined. A total of 50 fetuses, including 20 fetuses with Hb Bart's disease and 30 unaffected fetuses were recruited. There was a significant increase in the level of serum iron in the affected group (median: 22.7 vs. 9.7; p-value: 0.013) and also a significant increase in NTBI when compared with those of the unaffected fetuses (median 0.11 vs. 0.07; p-value: 0.046). In comparisons of fetal cardiac function, myocardial performance (Tei) index of both sides was significantly increased in the affected group (left Tei: p = 0.001, Right Tei: p = 0.008). Also, isovolumetric contraction time (ICT) was also significantly prolonged (left ICT: p = 0.00, right ICT: p = 0.000). Fetal LPI levels were significantly correlated inversely with fetal hemoglobin levels (p = 0.030) but not significantly correlated with the fetal serum iron levels (p = 0.138). Fetal LPI levels were also significantly correlated positively with myocardial performance index (Tei) of both sides (right Tei: R = 0.000, left Tei: R = 0.000) and right ICT (R = 0.013), but not significantly correlated with left ICT (R = 0.554). Anemia caused by fetal Hb Bart's disease in pre-hydropic stage is significantly associated with fetal cardiac dysfunction and increased fetal serum NTBI levels which are significantly correlated with worsening cardiac dysfunction. Nevertheless, based on the limitations of the present study, further studies including long-term data are required to support a role of fetal anemia as well as increased fetal serum NTBI levels in development of subsequent heart failure or cardiac compromise among the survivors, possibly predisposing to cardiovascular disease in adult life.

75-g oral glucose tolerance testing does not affect fetal cardiac doppler parameters in low-risk pregnant women

The study aimed to examine whether acute hyperglycemia, caused by the 75-g oral glucose tolerance test (OGTT) can produce fetal cardiac adverse effects that are detectable with fetal cardiac Doppler ultrasound in healthy low-risk pregnancies. Healthy low-risk pregnant women who underwent 75-g OGTT during the gestational period of 24 to 28 weeks were considered eligible and during the test, they were examined with fetal ultrasound at the fasting and 1- and 2-h timepoints. The study findings included the parameters of umbilical artery pulsatility index, uterine artery, fetal heart rate, middle cerebral artery (MCA) peak systolic velocity (MCA-PSV), MCA pulsatility index, and fetal cardiac Doppler parameters including myocardial performance index, left isovolumetric contraction and relaxation times, K-index, filling time, mitral E- and A-wave velocities, and E/A ratio. The data of 53 women without gestational diabetes mellitus were used for statistical analyses. There was no statistical significance among the three-time points of OGTT regarding all the Doppler parameters (p&gt;0.05). The median MCA-PSV measured at the fasting of OGTT was significantly higher than the values measured at the first and second hour of OGTT [28 (22-42) vs. 26 (18-39) and 26 (18-38), respectively; p&lt;0.05]. This increase provided no relationship with other study parameters (p&gt;0.05). Overall, 75-g OGTT does not affect fetal cardiac Doppler parameters in healthy pregnant women except for abnormal findings of MCA-PSV. The results of the current study can provide significant support to clinicians in reducing the hesitations of women with low-risk pregnancies regarding gestational diabetes screening.

Right ventricular myocardial performance index (Tei) in premature infants

The objective of this study was to evaluate the right ventricular myocardial performance index) based on echocardiography in very low birth weight premature neonates, close to hospital discharge. This was a prospective cross-sectional study that included premature neonates with birth weight <1,500 g and gestational age <37 weeks at the Intermediate Neonatal Unit of Bonsucesso Federal Hospital from July 2005 to July 2006. The infants underwent two-dimensional color Doppler echocardiography, being the right ventricular myocardial performance index evaluated close to hospital discharge. We compared the neonatal and echocardiographic variables in neonates with and without bronchopulmonary dysplasia. A total of 81 exams were analyzed. The mean birth (standard deviation) weight and gestational age were 1,140 (235) g and 30 (2.2) weeks, respectively. The incidence of bronchopulmonary dysplasia was 32%. The mean right ventricle myocardial performance index (standard deviation) of the sample was 0.13 (0.06). We found a significant difference in aortic diameter [non-bronchopulmonary dysplasia 0.79 (0.07) vs. bronchopulmonary dysplasia 0.87 (0.11) cm, p=0.003], left ventricle in diastole [non-bronchopulmonary dysplasia 1.4 (0.19) vs. bronchopulmonary dysplasia 1.59 (0.21) cm, p=0.0006], ventricular septal thickness [non-bronchopulmonary dysplasia 0.23 (0.03) vs. bronchopulmonary dysplasia 0.26 (0.05) cm, p=0.032], and "a" measurement [(= sum of the isovolumetric contraction time, ejection time, and isovolumetric relaxation time) when calculating the myocardial performance index (p=0.01)]. Higher "a" interval in neonates with bronchopulmonary dysplasia suggests right ventricle diastolic dysfunction. We conclude that the right ventricle myocardial performance index is an important indicator both of ventricular function and for serial follow-up testing of very low birth weight premature neonates, especially those with bronchopulmonary dysplasia.

849 EFFECTS OF INTRA-AORTIC BALLOON PUMP DELAYED DEFLATION TIMING ON CAROTID BLOOD FLOW AND CARDIAC MECHANICS

Abstract Background Intra-Aortic Balloon Pump (IABP) efficacy is critically affected by the inflation/deflation timing. Balloon deflation may cause a sucking effect, and a steal phenomenon on carotid flow. Delaying IABP deflation reduces the degree of this flow reversal, but at the same time exposes patients to the risk of increased proto-systolic afterload with detrimental effects on the LV. Hypothesis To investigate the effects of a delayed IABP deflation timing on cerebral blood flow and LV hemodynamics. Methods We prospectively evaluated 20 consecutive patients who received transfemoral IABP for cardiogenic shock (CS). Central aortic pressures (augmented diastolic [ADP], end-diastolic [EDP], assisted systolic [ASP] and mean aortic [MAP] pressures) were recorded from the IABP console simultaneously with ultrasound data. First ultrasound and haemodynamic measurements were collected during conventional IABP deflation timing (balloon deflation completed before onset of LV systole by automated ECG gating). Then, IABP deflation was manually delayed to the beginning of the QRS (early LV systole). After adjustment, counterpulsation was performed for a minimum of 2 minutes to achieve steady hemodynamics, then the same ultrasound and haemodynamic measurements were recollected. Results Mean age was 67±13 years, LVEF was 25±11%. At the carotid ultrasound, the delayed deflation increased the net forward velocity time integral (VTI) in the common carotid artery (18±9 vs 15±8 cm; p=0.001), by reducing the end-diastolic backward VTI (1±1 vs 4±2 cm; p&amp;lt;0.001) while having no effect on the overall forward VTI (19±9 vs 19±9 cm; p=0.294). Specifically, the delayed deflation increased the diastolic forward VTI (12±5 vs 10±4 cm]; p&amp;lt;0.001) while decreasing the systolic forward VTI (7±4 vs 9±4 cm]; p&amp;lt;0.005). On central aortic hemodynamics, the delayed deflation decreased the ASP (91±21 vs 97±20 mmHg; p=0.001), increased the EDP (60±11 vs 48±9 mmHg; p&amp;lt;0.001), the ADP (123±19 vs 119±19 mmHg; p&amp;lt;0.001) and the MAP (89±14 vs 80±12 mmHg; p&amp;lt;0.001). On echocardiography, the delayed deflation increased the LVOT VTI (15±4 vs 13±4 cm; p&amp;lt;0.001), decreased LV ejection time (202±44 vs 211±43 ms; p=0.005) but did not affect the isovolumetric contraction time (119±56 vs 119±58 ms; p=0.989), eventually reducing the total duration of LV systole (321±54 vs 330±50 ms; p=0.009). Conclusions In our cohort, a delayed IABP deflation strategy, evaluated by a multi-parametric yet relatively simple approach, demonstrated to be safe and was associated with both an increase cerebral perfusion and an improvement in cardiac mechanics.

Altered Fetal Cardiac Function in Smoking During Pregnancy

AbstractMaternal smoking during pregnancy remains a major public health issue and is associated with adverse perinatal outcomes. This study aimed to evaluate fetal cardiac functions in chronic maternal smoking during pregnancy and to compare them with non-smoker pregnant women. Forty-two smoker pregnant women between 24 and 34 weeks of gestation and gestational age-matched 44 non-smoker pregnant women were enrolled in this cross-sectional study. Fetal cardiac functions were measured using conventional Doppler echocardiography. The peak velocities of the mitral valve during early diastole (E) and atrial contraction (A) were measured, and the E/A ratio was calculated. The following time periods were also calculated; isovolumetric contraction time (ICT), isovolumetric relaxation time (IRT), and ejection time (ET). Then, the fetal left ventricle modified myocardial performance index (Mod-MPI) was calculated. No significant differences were noted between the groups in terms of E, A, and E/A ratio z-scores (p &gt; 0.05). The ICT and IRT z-scores were found to be significantly higher in the study group compared with those in the control group (p = 0.001 and p = 0.034). Mod-MPI z-score was also found significantly higher in the study group than in the control group (p = 0.034). There was no significant difference between the groups in terms of ET (p &gt; 0.05). The signs of systolic, diastolic, and global cardiac dysfunction were demonstrated in fetuses of pregnant women with chronic smoking. It, therefore, merits consideration that the fetal heart is also exposed to the detrimental effects of smoking.

Seismocardiography as a tool for assessment of bi-ventricular pacing

Objective. Conduction-induced heart failure in patients with left bundle branch block (LBBB) can benefit from cardiac resynchronization therapy (CRT). However, some patients are non-responders to the therapy with one contributing factor being poor optimization of the atrioventricular (AV) pacing delay. In this study, we have investigated the pacing-induced changes in the seismocardiogram (SCG). Approach. 14 patients with heart failure, LBBB, and CRT were included. SCG was recorded with pacing turned on and off. Based on a mean SCG heartbeat from each patient, fiducial points were annotated, and cardiac timing intervals (CTI) and amplitudes were derived. These were compared between the CRT group and a group of healthy normal subjects (n = 14). Echocardiography was also used to derive CTI. Intervals derived from the SCG and echocardiogram were correlated. Main results. The isovolumetric contraction time (IVCT) derived from SCG was significantly shorter in the CRT group when the pacemaker was turned on (63.2–52.6 ms, p = 0.027). The first peak-to-peak amplitude in the systolic complex was significantly larger with the pacemaker turned on (p = 0.002), as well as the ∣max-min∣ amplitude in the systolic complex (p = 0.003). Isovolumetric relaxation time and left ventricular ejection time (LVET) were not significantly different between pacemaker settings. Compared to normal subjects, IVCT was significantly prolonged with the pacemaker turned off. All amplitudes were significantly larger in the healthy subject group. IVCT and LVET derived from SCG were significantly correlated to the echocardiogram. Significance. IVCT shortened and SCG amplitudes increased in response to CRT, indicating a more efficient ventricular contraction. This demonstrates the possibility to detect cardio-mechanic changes in response to treatment with the SCG. However, for the patients the systolic part of the SCG was abnormal and difficult to characterize, raising concerns about the correct interpretation of the SCG.