205 - Congenital heart defect newborns with diastolic steal have altered cerebral arterial doppler profile during the transitional period

Poster Number: 205
Publication Number: 205.220

Marina Mir, McGill University - Montreal, QC, Montreal, PQ, Canada; Jessica simoneau, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada; Punnanee Wutthigate, Mahidol University, Thailand, Montreal, PQ, Canada; Gianluca Bertolizio, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada; Adrian Dancea, McGill University Faculty of Medicine and Health Sciences, Westmount, PQ, Canada; Shiran Sara Moore, McGill University Faculty of Medicine and Health Sciences, Westmount, PQ, Canada; Gabriel Altit, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada

Background: Resistive index (RI) of the anterior cerebral artery (ACA) measured by Doppler ultrasound (US) describes blood flow by accounting for peak systolic velocity (PSV) and end-diastolic velocity (EDV). RI is impacted by autoregulation and diastolic steal. Abnormal cerebral vascular integrity may lead to cerebral injury in newborns with congenital heart defect (CHD), especially in the context of cerebrovascular steal into the pulmonary circulation during the transitional period.

Objective: During the first 7 days of life, compare trends in the ACA doppler markers of vascular flow for CHD neonates with and without diastolic systemic steal.

Design/Methods: Prospective study recruiting newborns (≥35 weeks) with significant CHD requiring post-natal intensive care. We excluded preterm infants, those with significant genetic, syndromic or brain anomalies. Doppler US and echocardiography (ECHO) was performed daily from day 1 to 7 (or until discharge/intervention). The cohort was divided on the presence/absence of holo-diastolic retrograde flow in the post-ductal aorta on the last available ECHO. Data extractors were masked to the group status. Graphics for trends and mixed effect models (random slope/intercept) were constructed using RStudio

Results: 38 newborns were enrolled (82 consecutive CHD admission: 17 declined, 10 missed [COVID], 11 excluded, 5 missed [unavailable personnel] and 1 discharged prior entry). A ductus was patent on last ECHO in 28 (74%), with retrograde aortic flow in 23 (61%) had. Gestational age and birth weight were similar between groups, but those with retrograde flow were more likely males (Table 1). The ACA PSV significantly increased in time (Retrograde: =↑0.05cm/s/US, p=0.006; No-Retrograde: =↑0.10cm/s/US, p < 0.001, being the daily increase or slope), while the EDV and RI were unchanged (Table 2 – Panel A). The mean velocity (Vm) increased (=0.05cm/s, p=0.01) in those without retrograde flow, but did not change in those with retrograde flow. Retrograde group showed overall lower EDV (: -5.75 cm/s, p < 0.001) and higher RI (:0.16, p < 0.001) - Table 2 – Panel B.i. With regards to the entire cohort, PSV, RI and Vm significantly increased over time (Table 2 – Panel B.ii).Conclusion(s): Neonates with CHD and systemic diastolic steal in the first week of life demonstrate a change in the cerebral arterial Doppler profile. Retrograde aortic flow was associated with an increased RI and decreased EDV, possibly secondary to the progressive steal in the pulmonary circulation. Future studies should evaluate the impact of such vascular flow anomalies on brain injury and long-term prognosis.
CV Marina MirCV MARINA MIR-PARRAMON 2021.pdf
Table 2: Random mixed effect model for relationship between ACA Doppler markers and Retrograde flow in time or Day of Life at ultrasound