Tissue Doppler Derived Longitudinal Strain and Strain Rate During the First 3 Days of Life in Healthy Term Neonates

Abstract

Tissue Doppler derived longitudinal strain and strain rate were studied in 48 healthy term neonates by measuring peak systolic strain (PSS) and peak systolic strain rate (PSSR) in 18 heart segments on day 1-3 of life. The mean PSS for each examination was Ϫ21.8% (Ϫ22.1, Ϫ21.4) ͓mean (95%CI)͔, and the mean PSSR was Ϫ1.78/s (Ϫ1.81, Ϫ1.74). Age (d), fetal shunts, and heart rate had negligible impact on measurements for any segment. The fractional shortening had negligible impact on septum and left heart segments and the pulmonary artery pressure had no impact on the right heart segments. Values varied significantly between segments and individuals, and were lower (closer to zero) in images of low quality than in images of high quality (p Ͻ 0.05). Both apical and basal segments values were lower in the septum and higher in the right ventricle than in the left ventricle (p Ͻ 0.05), except for no difference between the basal left and right segments PSSR. Apical segments values were higher than basal segments values in the right ventricle (p Ͻ 0.05) but not in the septum or the left ventricle. At present, PSS and PSSR are more feasible for quantifying differences between segment groups and patient groups than between individuals and segments within individuals. Strain describes the relative change in heart segment length and strain rate is strain per time unit. Data on strain and strain rate measurements in neonates are scarce. We have previously found strain and strain rate by tissue Doppler feasible and reliable in neonates (2). Little is known about changes in myocardial function during the first days of life, when the hemodynamic circulatory system changes from two parallel to one serial circuit, the gas exchange is transferred from the placenta to the lungs and the fetal shunts are gradually closed (3). Strain and strain rate measurements could provide new knowledge about the myocardial function during these changes, and also serve as a reference for studies of the heart function in pathologic states during this period.The aim of the present study was to investigate myocardial contraction in healthy term neonates by measuring longitudinal peak systolic strain (PSS) and strain rate (PSSR) in the first 3 days of life and assess the impact of age, fetal shunts, image quality, and different heart regions. METHODSSubjects. Forty-eight healthy term neonates from the maternity ward at Ullevål University Hospital were examined on the first, second, and third day of life (March-May 2005) ( Table 1). One neonate had an apical ventricular septum defect. The measurements from this neonate were not excluded because the defect was without hemodynamic significance and lied outside the myocardial region used in the analyses. All other neonates had structurally normal hearts.The project was approved by the Regional Committee for Medical Research Ethics and by the scientific committee at Ullevål University Hospital. Written informed parental consent was obtained.Measurements. To minimize noise in the analyses, a 2.4 MHz p...

Transthoracic Echocardiography in the Evaluation of Pediatric Pulmonary Hypertension and Ventricular Dysfunction

“…66 Deformation imaging has also been performed in healthy and asphyxiated neonates. [67][68][69] Reduced longitudinal RV deformation has been shown in patients with congenitally corrected transposition of the great arteries suffering from increased RV afterload. 70 Dragulescu and Mertens 71 showed that speckle-tracking techniques can be used in children to quantify longitudinal and circumferential strain.…”

Longitudinal Assessment of Left and Right Myocardial Function in Preterm Infants Using Strain and Strain Rate Imaging

“…There has been recent interest in describing myocardial function in preterm infants using tissue Doppler imaging (TDI)-derived strain and strain rates [1,2,3,4,5,6]. The longitudinal systolic strain, systolic and diastolic strain rates have proven to be valuable diagnostic tools in adults, children and term infants [7,8,9,10,11].…”

Myocardial function in premature infants: a longitudinal observational study

“…8 TDI is increasingly used to assess ventricular function in adults, 10 11 and there are several cross-sectional studies reporting feasibility applying TDI in neonates and children. [12][13][14][15][16][17][18] However, studies in moderately preterm infants are scarce and usually include few participants. Premature birth is an adverse event that can disturb the normal cardiovascular physiology.…”

“…Fifty-five premature infants were included and examined at median (range) postnatal age 13 (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21), 38 (26-48) and 64 (54-72) h. The term examinations were conducted at 40 +1 (38 +2 -42 +6 ) weeks +days . The need for respiratory support is depicted in table 2.…”