Right Atrial Dysfunction Is Prevalent in Pediatric Acute Respiratory Distress Syndrome and Reflects Pulmonary Hypertension and Right Ventricular Dysfunction.

Importance: Right atrial (RA) dysfunction is associated with worse outcomes in some populations with pulmonary hypertension or respiratory failure but the prevalence and correlates of RA dysfunction in pediatric acute respiratory distress syndrome (PARDS) are unknown.

Objectives: The aim of this study was to evaluate RA function by characterizing the prevalence and pattern of RA dysfunction within the first 24 hours of PARDS onset. We hypothesized that RA dysfunction would be common and correlate with the presence of pulmonary hypertension and right ventricular (RV) systolic dysfunction.

Design, setting, and participants: Retrospective, single-center cohort study at a tertiary care PICU of children (< 18 yr) with a clinically obtained echocardiogram within 24 hours following PARDS diagnosis and healthy controls without cardiopulmonary disease.

Main outcomes and measures: Echocardiograms were evaluated for conventional and speckle-tracking (or strain) echocardiographic measures of RA and RV systolic function. Nonparametric summary statistics, comparisons, and correlational analyses were completed.

Results: Ninety-two PARDS patients and 55 controls were included. Using a priori thresholds (> 2 sds of control values), 49% (n = 45) of PARDS patients demonstrated RA dysfunction in at least one RA functional metric. The maximal RA strain during the reservoir phase was reduced in PARDS compared with controls (median 40.2% vs. 53.7%; p < 0.001). Patients with echocardiographic evidence of pulmonary hypertension had lower maximal RA strain during the reservoir phase (31.7%) compared with patients without (40.5%; p < 0.05). Patients with higher brain-type natriuretic peptide plasma concentrations had worse RA function. RA function significantly correlated with conventional and strain measures of RV systolic function.

Conclusions and relevance: RA dysfunction is common within the first 24 hours of PARDS onset. RA dysfunction during the reservoir phase is associated with pulmonary hypertension and RV systolic dysfunction. Future studies investigating trajectories of RA function and their association with outcomes in PARDS patients are needed.