Myocardial function in premature infants: a longitudinal observational study

Abstract

ObjectivesGestational and chronological age may have an impact on myocardial function. We studied the longitudinal changes of the atrioventricular tissue Doppler velocities in premature infants through the neonatal transitional period and at expected term and explored the reproducibility of the measurements.DesignProspective, observational and longitudinal cohort study.SettingTwo-centre study, from a secondary and a tertiary neonatal intensive care unit.Participants55 infants (29 males) with gestational age 31–35 weeks and birth weight 1127–2836 grams.Primary and secondary outcome measuresPulsed-wave atrioventricular left, septum and right ventricular annulus tissue Doppler systolic (S′), early diastolic (E′) and late diastolic (A′) velocities measured by repeated echocardiographic examinations days 1, 2 and 3 and at expected term.ResultsAll velocities increased significantly from the neonatal period to expected term (p<0.001). We found a significant correlation between gestational age and right-sided S′, E′ and A′ on day 1 (Pearson correlation 0.32–0.46, p<0.05), for S′ in all three walls and septal E′ and A′ on day 2 (Pearson correlation 0.27–0.49, p<0.05). There was a moderate linear correlation between left ventricle end-diastolic length and septal and right S′ at term and for septal E′ and A′ at day 1 (Pearson correlation 0.30–0.56, p<0.05). We found no correlation between heart rate and tissue Doppler velocities when controlling for the effect of fusion. Continuous positive airway pressure showed moderate effect where as persistence of the ductus arteriosus showed no effect on the tissue Doppler velocities. The E′/A′ relationship was consistently reversed throughout the study with frequently fused diastolic tissue velocity signals.ConclusionsPulsed-wave atrioventricular annulus tissue Doppler velocities were related to gestational age, postnatal age and ventricular size. Right ventricle velocities showed more pronounced increase with postnatal maturation than left ventricle velocities. The degree of E′/A′ fusion influenced the diastolic tissue Doppler velocities and should be reported if present.

Tissue Doppler velocity imaging and event timings in neonates: a guide to image acquisition, measurement, interpretation, and reference values

“…Large hearts have higher velocities and displacements than small hearts. 36 , 37 To compare between hearts of different sizes, the neonatologist can normalize measurements for cardiac size. Neonatal studies have often used end-diastolic septal length or length from apex to the lateral AV-plane hinge for normalization for size 38 , 39 and reported velocities and excursions normalized by LV length in neonates and children.…”

“…Studies of displacement have used cTDI and most studies of time intervals have used pwTDI. There are several studies describing reference ranges of tissue Doppler velocities and displacements from the apical four-chamber view in premature neonates 5 , 6 , 12 , 36 , 38 , 40 , 42 , 46 , 50 – 55 and term neonates. 6 , 11 , 12 , 32 , 51 , 52 , 54 , 56 , 57 Some are longitudinal studies with repeated measurements over days and weeks.…”

Myocardial Function Maturation in Very-Low-Birth-Weight Infants and Development of Bronchopulmonary Dysplasia

“…Nevertheless, they found similar left ventricle function to that of term newborns after the transitional period (34). Eriksen et al (35) described differences in late preterm TDI measures from the transitional period to the term-corrected age. Interestingly, normative TDI values in term newborns and in VLBWIs have been based on studies performed during the transitional period (26).…”

Систолічна Та Діастолічна Функції Міокарда У Новонароджених У Ранній Неонатальний Період.

“…Розуміння даного питан-ня сприяє вирішенню ряду фундаментальних проблем післяпологової перебудови гемодинаміки. У перспективі новонароджений повинен успішно перейти до позаутробного існування без різких змін у кардіореспіраторній системі, включаючи зміни в обсязі легенів і зміни переднавантаження та постнавантаження на ліві й праві відділи серця, що має відбиток на функціональному стані міокарда [3]. Відповідно до рекомендацій American Society of Echocardiography (ASE) in collaboration with the European Association of Echocardiography (EAE) and the Association for European Pediatric Cardiologists (AEPC), цільова неонатальна ехокардіографія повинна проводитись як доповнення до клінічної оцінки стану гемодинаміки у новонароджених [4].…”