Serial changes in myocardial function in preterm infants over a four week period: the effect of gestational age at birth ☆ Muhammad Shahid Hussain Saleemi a, ⁎,Afif El-Khuffash a , Orla Franklin b , John David Corcoran a,c a Department of Neonatology, Rotunda Hospital, Dublin, Ireland b Department of Cardiology, Children’s University Hospital, Temple Street, Dublin, Ireland c Department of Paediatrics, Trinity College University, Dublin, Ireland abstract article info Article history: Received 16 January 2014 Received in revised form 7 April 2014 Accepted 12 April 2014 Available online xxxx Keywords: Myocardial performance Preterm infants Tissue Doppler imaging Background: Myocardial performance is impaired in the first days of life in preterm infants but improves by day 5. Tissue Doppler imaging (TDI) is a novel and reliable means of assessing myocardial performance. Objective: To investigate myocardial performance using TDI and shortening fraction (SF) in preterm infants of different gestational age groups and serial changes in these parameters in first four weeks of life. Study design Infants less than 36 weeks of gestation were divided into group 1 (24–27 weeks, n = 8), group 2 (28–31 weeks, n = 12) and group 3 (32–35 weeks, n = 13). Infants with severe congenital malformations, a hypoxic insult at birth, and those on inotropic support were excluded. Echocardiograms were performed at 36–48 hours, 2 weeks and 4 weeks of life. Left ventricular (LV) SF, systolic (S′), early diastolic (E′) and late diastolic (A′) TDI velocities were assessed. We analyzed the data using a repeated-measures ANOVA. Results: Thirty three infants underwent serial TDI and SF measurements. There was an increase in LV S′ (p = .02) and E′ (.01) velocities in group 2 , and in group 3 (p = .03 for S′ and p = .04 for E′), but no significant increase in group 1 (p = .48 for S′ and .32 for E′). At each study point, there was significant difference in myocardial perfor- mance between group 1 and 3 for each of the parameters (p b .05). There was no significant increase in SF over time in any of the groups. Conclusion: We describe a serial increase in myocardial performance in infants of 28 weeks gestation and above. While there was no change in myocardial performance among the most extremely preterm infants, this may have been the result of small sample size of the group. © 2014 Elsevier Ireland Ltd. All rights reserved. 1. Introduction The preterm myocardium is characterized by reduced diastolic func- tion and intolerance to increased afterload, due to the inefficient con- tractile mechanism and lack of adequate elastic recoil[1]. The impact of these inherent structural differences, and of premature delivery on myo- cardial function in the first few weeks of life, warrants further study. Tissue Doppler imaging (TDI) is an emerging tool for the assessment of myocardial performance in preterm infants [2,3]. TDI directly mea- sures myocardial velocities allowing quantitative assessment of systolic and diastolic function of both ventricles [4,5]. TDI measures muscle movement velocity by assessing the high amplitude, low velocity ultra- sound signals reflected from muscle wall movement while suppressing high velocity, low amplitude signals reflected from moving fluid [6]. The high temporal resolution of TDI is suited for the fast heart rates of pre- term infants [5]. Several studies have demonstrated that assessment of myocardial velocity using TDI is feasible in the preterm population with acceptable reproducibility [2,5,7,8]. Assessment of myocardial function using TDI may be more accurate than conventional measures of myocardial performance which rely on the change in the dimensions of the ventricular cavity, namely shorten- ing (SF) and ejection (EF) fraction [9–11]. In addition to being less sen- sitive, those conventional markers are very heavily load dependent and may not accurately reflect myocardial function. Recent studies have demonstrated the superiority of TDI in detecting myocardial dysfunc- tion when compared to SF and EF [4,12]. Following patent ductus arteriosus (PDA) ligation, TDI can identify myocardial dysfunction in the subset of infants who develop clinical hypotension [13]. In addition, TDI can demonstrate significant improvement in myocardial perfor- mance following blood transfusion in anemic infants. SF fails to demon- strate those changes [4]. In this study, we investigated myocardial performance values for left ventricular peak myocardial systolic (S′), early diastolic (E′) and late diastolic (A′) TDI velocities and shortening fraction (SF), in preterm Early Human Development xxx (2014) xxx–xxx ☆ No financial support was sought for this research work. ⁎ Corresponding author at: Department of Neonatology, National Maternity Hospital, Dublin 2, Ireland. Tel.: +353 16373100; fax: +353 16614623. E-mail address: dr_shahid_saleemi@yahoo.com (M.S.H. Saleemi). EHD-03956; No of Pages 4 http://dx.doi.org/10.1016/j.earlhumdev.2014.04.012 0378-3782/© 2014 Elsevier Ireland Ltd. All rights reserved. Contents lists available at ScienceDirect Early Human Development journal homepage: www.elsevier.com/locate/earlhumdev Please cite this article as: Saleemi MS, et al, Serial changes in myocardial function in preterm infants over a four week period: the effect of gestational age at birth, Early Hum Dev (2014), http://dx.doi.org/10.1016/j.earlhumdev.2014.04.012