biostudies-literatureMiles KGNational Center for Advancing Translational SciencesJayden DeLuca FoundationCollege of Medicine, University of CincinnatiNCATS NIH HHSCincinnati Children&apos;s Hospital Medical CenterNational Institutes of Health101962https://www.ebi.ac.uk/biostudies/studies/S-EPMC12702102biostudies-literatureUnknown27(2)<h4>Background</h4>Impaired right atrial (RA) function is strongly predictive of adverse outcomes in adults with pulmonary arterial hypertension (PAH) but remains incompletely understood in pediatric PAH. In this pediatric multi-center retrospective cohort study using cardiovascular magnetic resonance imaging (CMR), we analyzed RA size and phasic function and its associations with PAH severity.<h4>Methods</h4>PAH and control pediatric patients from two centers who underwent CMR from 2010 to 2023 were identified. RA volumes were measured throughout the cardiac cycle using the single-plane, area-length method on a standard 4-chamber cine sequence. Total, conduit phase, and active phase stroke volume (SVi; indexed to BSA) and ejection fraction (EF) were calculated. A novel marker, the A/C ratJournal of cardiovascular magnetic resonance : official journal of the Society for Cardiovascular Magnetic ResonanceRight Atrial Function is Impaired in Pediatric Pulmonary Arterial Hypertension: A Multi-center Cardiovascular Magnetic Resonance Study.PMC12702102UL1 TR002535Cash MFrank BSMiles KGOllberding NJLuebbe KLang SMTa HTMagness MO'Neil MCritser PJHirsch RBjorkman KRGao ZIvy DDfalseRight Atrial Function is Impaired in Pediatric Pulmonary Arterial Hypertension: A Multi-center Cardiovascular Magnetic Resonance Study.<h4>Background</h4>Impaired right atrial (RA) function is strongly predictive of adverse outcomes in adults with pulmonary arterial hypertension (PAH) but remains incompletely understood in pediatric PAH. In this pediatric multi-center retrospective cohort study using cardiovascular magnetic resonance imaging (CMR), we analyzed RA size and phasic function and its associations with PAH severity.<h4>Methods</h4>PAH and control pediatric patients from two centers who underwent CMR from 2010 to 2023 were identified. RA volumes were measured throughout the cardiac cycle using the single-plane, area-length method on a standard 4-chamber cine sequence. Total, conduit phase, and active phase stroke volume (SVi; indexed to BSA) and ejection fraction (EF) were calculated. A novel marker, the A/C rat2025-01-01T00:00:00Z2025 Sep2026-06-06T03:46:07.09Z2026-05-25T03:11:25.638ZS-EPMC127021024097645210.1016/j.jocmr.2025.101962