Preterm infants < 29 weeks gestation underwent echocardiography assessments on days 1, 2 and 5–7. RVEDA and RVESA were traced in the RV-focused apical four-chamber view, and RV FAC was calculated using the formula [(RVEDA − RVESA) ÷ (RVEDA)] × 100. PDA treatment was not carried out during the study period. A cranial ultrasound was carried out on all infants on Days 5–7 of age. P/IVH was defined as IVH grades II to IV.
One hundred and one infants with a mean gestation of 26.5 (1.4) weeks and a birthweight of 983 (240) grams were enrolled in the study. There was no relationship between RV FAC and birthweight (r = − 0.02, p = 0.86) but there was a negative correlation between RV FAC and echo-measured SVR (r = − 0.57, p < 0.001). On Day 1, RV FAC was lower in infants who developed P/IVH (24% [18–34] vs. 31% [25–40], p = 0.04). On Days 5–7 infants with a PDA had a lower RV FAC compared with those without [42 (7) vs. 49 (9) %, p < 0.001].
RV FAC may be a useful addition to the haemodynamic assessment of preterm infants during the first week of age.