Assessment of fetal cardiac function using tissue Doppler techniques.
ABSTRACT Tissue Doppler echocardiography is being increasingly used in fetal medicine as a clinical and research tool. The objective of this study was to review the current status of tissue Doppler imaging (TDI) techniques applied to the fetus.
Fetal cardiac function was evaluated using spectral and color TDI modes in normal fetuses and in several clinical conditions.
Annular peak velocities and their ratios as well as the myocardial performance index were evaluated using spectral TDI, and changes throughout gestation were described. Color TDI has several limitations in fetal life, particularly the use of low frame rates with current methods of acquisition and the lack of normal references for deformation parameters.
Despite its limitations, TDI is a sensitive and promising method to evaluate fetal cardiac function.
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ABSTRACT: This study investigated cardiac function in 65 fetuses of mildly preeclamptic mothers and 55 fetuses of healthy mothers at 26-40 weeks of gestation. Fetuses with intrauterine growth restriction were excluded. Cardiac functions were evaluated by M-mode, pulsed-wave, and tissue Doppler echocardiography. The two groups were similar in terms of maternal age, gravidity, parity, and gestational age. Peak systolic aortic and pulmonary artery velocities were significantly lower in the fetuses of the preeclamptic mothers than in the fetuses of the healthy mothers. The two groups did not differ significantly in terms of shortening fraction or with regard to mitral or tricuspid annular plane systolic excursion. Pulsed-wave Doppler-derived E/A ratios in the mitral and tricuspid valves were similar in the two groups. The deceleration time of early mitral inflow was prolonged in the fetuses of the preeclamptic mothers. The Ea, Aa, and Ea/Aa ratios in the interventricular septum, left ventricle posterior wall, and right ventricle free wall were lower in the preeclampsia group than in the control group. The E/Ea ratio was higher in the preeclampsia group than in the control group. The isovolumic relaxation time and the right and left myocardial performance indices were higher in the fetuses of the preeclamptic mothers than in the fetuses of the healthy mothers. An increased ductus venosus pulsatility index (PI) and a decreased middle cerebral artery (MCA) PI were found in the fetuses of the preeclamptic mothers. All the fetuses were asymptomatic. The results suggest that the increase in fetal cardiac afterload in mild preeclampsia may have caused early subclinical changes in fetal systolic and diastolic cardiac function. In addition, the decrease in MCA-PI may have been caused by redistribution of fetal cardiac output in favor of the left ventricle, secondary to increased placental vascular resistance.Pediatric Cardiology 04/2013; · 1.20 Impact Factor
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ABSTRACT: Although many echocardiographic parameters can assess cardiac function noninvasively in preterm infants, it has not been determined what indices are the best. We assessed left-ventricular performance in 101 very low-birth weight (VLBW) infants using tissue Doppler imaging (TDI) echocardiography. Echocardiographic examinations, including TDI, were performed serially within 7 days of life. Pulsed-Doppler TDI waveforms were recorded at the mitral valve annulus, and peak systolic velocities (Sa), early diastolic velocities (Ea), and late diastolic velocities (Aa) were measured. Sa and Aa velocities were both decreased significantly from 3 to 12 h and then gradually increased. Ea velocities showed no significant, longitudinal changes, but Ea values in premature groups appeared to be significantly lower than those in mature groups. The ratio of E to Ea (E/Ea) of VLBW infants seemed to be almost stable from birth to day 7, and this also showed no significant differences between different gestational age groups. E/Ea values in infants with patent ductus arteriosus (PDA) appeared to be greater than those in non-PDA infants. Our present findings suggest that TDI assessment in the early neonatal period might be useful in detecting latent systolic/diastolic failure of critically ill preterm infants.Pediatric Cardiology 03/2013; · 1.20 Impact Factor