Neidin Bussmann1, Aisling Smith1, Alessia Cappelleri1, Phillip T Levy2, Naomi McCallion1,3, Orla Franklin4, Afif El-Khuffash1,3. 1. Department of Neonatology, The Rotunda Hospital, Dublin, Ireland. 2. Division of Newborn Medicine, Boston Children's Hospital, Boston, MA, USA. 3. Department of Paediatrics, School of Medicine, Royal College of Surgeons in Ireland, Dublin, Ireland. 4. Department of Paediatric Cardiology, Our Lady's Children's Hospital Crumlin, Dublin, Ireland.
Abstract
BACKGROUND: Speckle tracking echocardiography (STE) is a validated method to measure longitudinal deformation in premature infants, but there is a paucity of data on STE-derived circumferential and radial strain in this population. We assessed the feasibility and reproducibility of circumferential and radial deformation measurements in premature infants. METHODS: In a prospective study of 40 premature infants (<29 weeks of gestation at birth), STE-derived circumferential and radial strain, systolic strain rate (SRs), early diastolic strain rate (SRe), and late diastolic strain rate (SRa) were measured on day 2 and day 8. Intra- and inter-observer reproducibility analysis were performed using Bland-Altman analysis, coefficient of variation (COV), and intra-class correlation coefficient (ICC). The impact of a persistent patent ductus arteriosus (PDA) was analyzed. RESULTS: Deformation analysis was feasible in 98% of the acquisitions. Circumferential parameters demonstrated excellent intra- and inter-observer reproducibility with an ICC between 0.89 and 0.99 (all P < 0.001) and a COV between 4% and 13%. Radial parameters demonstrated acceptable intra- and inter-observer reproducibility with an ICC between 0.73 and 0.96 (all P < 0.001) and a COV between 14% and 27%. Infants with a PDA on day 8 (n = 21, 53%) demonstrated higher radial strain, SRs and SRe. There were no differences in circumferential parameters with a PDA at either time point. CONCLUSION: This study demonstrates clinical feasibility and reproducibility of circumferential and radial strain by STE in premature infants. A PDA elevates radial deformation measures, suggesting that the increased LV preload from a PDA may augment intrinsic contractility in the radial but not circumferential plane.
BACKGROUND: Speckle tracking echocardiography (STE) is a validated method to measure longitudinal deformation in premature infants, but there is a paucity of data on STE-derived circumferential and radial strain in this population. We assessed the feasibility and reproducibility of circumferential and radial deformation measurements in premature infants. METHODS: In a prospective study of 40 premature infants (<29 weeks of gestation at birth), STE-derived circumferential and radial strain, systolic strain rate (SRs), early diastolic strain rate (SRe), and late diastolic strain rate (SRa) were measured on day 2 and day 8. Intra- and inter-observer reproducibility analysis were performed using Bland-Altman analysis, coefficient of variation (COV), and intra-class correlation coefficient (ICC). The impact of a persistent patent ductus arteriosus (PDA) was analyzed. RESULTS: Deformation analysis was feasible in 98% of the acquisitions. Circumferential parameters demonstrated excellent intra- and inter-observer reproducibility with an ICC between 0.89 and 0.99 (all P < 0.001) and a COV between 4% and 13%. Radial parameters demonstrated acceptable intra- and inter-observer reproducibility with an ICC between 0.73 and 0.96 (all P < 0.001) and a COV between 14% and 27%. Infants with a PDA on day 8 (n = 21, 53%) demonstrated higher radial strain, SRs and SRe. There were no differences in circumferential parameters with a PDA at either time point. CONCLUSION: This study demonstrates clinical feasibility and reproducibility of circumferential and radial strain by STE in premature infants. A PDA elevates radial deformation measures, suggesting that the increased LV preload from a PDA may augment intrinsic contractility in the radial but not circumferential plane.