The impact preload on left ventricular three-plane deformation measurements in extremely premature infants

Left Ventricular (LV) deformation analysis using two-dimensional speckle tracking echocardiography (STE) is an emerging modality in premature infants.

To assess the impact of increased preload on LV deformation in three planes: longitudinal, circumferential and radial in premature infants.

Infants recruited to the PDA RCT (ISRCTN 13281214) and survived to discharge were included with the cohort divided into infants who closed their patent ductus arteriosus (PDA) by Day 8 (Low preload, PDA Closed) and those who maintained ductal patency (high preload, PDA Open).

Longitudinal, circumferential and radial strain and systolic strain rate (SRs) were measured at 36 h, Days 4 & 8 and 36 weeks.

61 infants were included. The PDA open Group had a lower gestation (26.4 vs. 27.4 weeks, p < 0.01) with a median PDA exposure of 30 days (vs. 2 days, p < 0.01), and demonstrated echocardiography evidence of pulmonary overcirculation. There was higher LV longitudinal strain and SRs over the first 3 scans in the PDA Open Group. Circumferential strain was higher over the first 2 scans while circumferential SRs was higher at 36 h. Radial Strain and SRs were only higher on Day 4.

Increased preload is associated with higher strain and systolic strain rate values in the premature population indicating that preload has a significant effect on deformation measurements in this population across all three planes.