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Purpose To use two-dimensional speckle tracking imaging(2D-STI)to evaluate left ventricular myocardial strain in term and preterm neonates.Materials and Methods A total of 81 neonates who accepted echocardiography in Soochow University Affiliated Children's Hospital from February to August 2018 were retrospectively enrolled,including 42 term neonates and 39 preterm neonates.Longitudinal and circumferential peak strain of each segment of left ventricle were measured by 2D-STI,and the average global longitudinal peak strain(GLPS-avg)and the average global circumferential peak strain(GCPS-avg)of left ventricular were measured too.Left ventricular ejection fraction(LVEF-M,LVEF-Simpson),short-axis shortening rate(LVFS-M),left ventricular end-diastolic diameter(LVEDD),and tissue Doppler imaging parameters(E',A' and E'/A')of the septal mitral annulus were also measured.The differences in each segment of left ventricle and echocardiography between term neonates and preterm neonate were further compared.Results There were statistically significant differences in GLPS-avg,the global longitudinal peak strain from the apical two-chamber view(GLPS-a2c),GCPS-avg and the global circumferential peak strain in the middle and apical segments(GCPS-M ang GCPS-A)(t=-3.60--2.18,all P<0.05)between term neonates and preterm neonates,while there were no significant differences between the global longitudinal peak strain from the apical four-chamber and three-chamber view(GLPS-a4c and GLPS-a3c),the global circumferential peak strain in the basal segments(GCPS-M)(all P>0.05).There were statistically significant differences in GLPS-a4c,GLPS-a2c,GLPS-a3c in preterm neonates group(F=3.20,P=0.044),and the strain value GLPS-a4c was the highest.There were statistically significant differences in GCPS-B,GCPS-M,GCPS-A in preterm neonates group(F=79.15,P<0.001).There were statistically significant differences in GCPS-B,GCPS-M,GCPS-A in term neonates group(F=97.95,P<0.001),and the strain value increased from the basal segment to the apical segments.There was statistically significant difference in LVEDD between term neonates and preterm neonates(all P<0.05).There were no statistically significant differences in LVEF-M,LVEF-Simpson,LVFS-M,E',A' and E'/A' between term neonates and preterm neonates(all P>0.05).Conclusion 2D-STI may be a useful method of measuring left ventricular myocardial systolic function and can provide early detection of differences in left ventricular myocardial contraction between term and preterm neonates.
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Objective:To study the role of myocardial work parameters in early identification of myocardial injury in neonatal asphyxia.Methods:From July 2020 to December 2021, neonates diagnosed with mild neonatal asphyxia admitted to the Department of Neonatology of our hospital within 24 h after birth were prospectively enrolled into the asphyxia group. Neonates without asphyxia during the same period were selected as the control group and matched with the asphyxia group for gender, gestational age and birth weight at a ratio of 1:1~1:2. The asphyxia group was subgrouped into preterm asphyxia group and term asphyxia group. All neonates received echocardiography within 24 h after birth. Multiple parameters were measured including M-mode, two-dimensional image, Doppler image, global longitudinal strain (GLS) and myocardial work parameters [global work index (GWI), global constructive work (GCW), global wasted work (GWW), global work efficiency (GWE)]. The level of serum N-terminal pro brain natriuretic peptide (NT-proBNP) was recorded in the asphyxia group. The data were compared between the asphyxia group and the control group. Correlations between myocardial work parameters and other parameters were analyzed.Results:A total of 33 cases were in the asphyxia group and 43 cases were in the control group. The preterm asphyxia group (18 cases) showed significantly lower GWI and GCW than the preterm control group (18 cases) [GWI: (702±153) mmHg vs. (879±205) mmHg, GCW: (1 016±221) mmHg vs. (1 200±271) mmHg] ( P<0.05). No differences existed in GLS, GWW and GWE. The term asphyxia group (15 cases) showed significantly lower GWW than the term control group (25 cases) [45.0 (30.0, 65.0) mmHg vs. 71.0 (35.5,85.5) mmHg] ( P<0.05). No differences existed in GLS, GWI, GCW and GWE. GWI was negatively correlated with serum NT-proBNP level ( r=-0.327, P<0.05). Conclusions:GWI and GCW may indicate myocardial injury in preterm neonates with mild asphyxia.