Right Ventricular Diastolic Filling in the First Day of Life.

Abstract

To evaluate the effects of altered preload on the Doppler flow pattern of right ventricular inflow in the first day of life, serial Doppler echocardiography of the pulmonary artery (PA) and tricuspid valve was performed in 16 normal neonates at 2, 12, and 24 hr. A computerinterfaced digitizer pad was utilized to measure the followings: PA flow velocitytime integral, total transtricuspid flow velocity-time integral, flow velocity-time integral of early diastolic filling (E area), and flow velocity-time integral of atrial contraction (A area). The PA flow velocity-time integral, total transtricuspid flow velocity-time integral, E area, A area, peak E, and peak A were increased significantly by 24 hr compared with the values at 2 hr of age. However, the peak E/A, E/A area and peak E/total transtricuspid flow velocity-time integral did not show significant changes from 2 to 24 hr. The ductus arteriosus size was inversely correlated with the peak E (r= -0.46, p <0.05), E area (r= -0.37, p <0.05), and A area (r= -0.34, p <0.05). Therefore, the increase in right ventricular preload at 24 hr is considered to be due to the cessation of the left-to-right shunt through the ductus arteriosus. These results suggest that the pattern of early and late diastolic filling of the right ventricle were dependent on the increase in preload. We can therefore conclude that the redistribution of transtricuspid flow induced by the preload condition should be taken into account to interprete the transtricuspid velocity pattern in terms of diastolic function. right ventricular diastolic function; neonate; ductus arteriosus Pulsed Doppler echocardiography has recently been used to assess right ventricular diastolic filling in a variety of diseases including valvular pulmonic stenosis, pulmonary hypertension, constrictive pericarditis and cardiac tamponade (Appleton et al. 1988;Hatle et al. 1989;Klein et al. 1990;Vermilion et al. 1990,

Serial evaluation for myocardial performance in fetuses and neonates using a new Doppler index

“…The early decrease that was observed in the Tei index most likely reflects the alterations in cardiac loading that result from the increase in pulmonary blood flow attendant to the onset of pulmonary ventilation. The transition to postnatal circulation includes a sudden decrease in pulmonary vascular resistance and shift of cardiac output from the right to left ventricle 27 –29 …”

Pulsed wave Doppler tissue echocardiography assessment of the long axis function of the right and left ventricles during the early neonatal period

“…5 On the other hand, Ew of the mitral annulus did not change significantly. Harada and colleagues 6 reported that tricuspid E increases within 24 hours after birth, probably due to an increase in the right ventricular preload and decreased right ventricular afterload. Ew of the tricuspid annulus did not change significantly during this period, unlike Ew of the mitral annulus.…”

“…There are several reports concerning changes in the mitral and tricuspid flow patterns during the neonatal period. [4][5][6] On the other hand, tissue Doppler echocardiography allows the recording of myocardial contraction and relaxation velocity. Pulsed wave Doppler tissue (PWDT) echocardiography can be used to analyse the long axis function of both ventricles, which is difficult to evaluate by conventional echocardiographic methods.…”

Color M‐mode propagation velocity, but not its ratio to early diastolic inflow velocity, changes throughout gestation in normal human fetuses

“…This discrepancy may reflect differences in developmental changes in the diastolic properties of the myocardium between the two ventricles, poorer RV compliance 20,21 and in-utero right heart dominance 22 .…”