Outcome of patients with atrial septal defect (ASD) and severe pulmonary arterial hypertension (PAH) relates to right ventricular (RV) function. Magnetic resonance imaging (MRI) remains the gold standard for evaluating the RV function but it is not used routinely. We investigated the relationship between MRI and multiple echocardiography parameters, including the Right Ventricle End-Systolic Remodelling Index (RVESRI), a new prognostic marker in patients with PAH.

A total of 23patients with ASD and severe PAH (median age 49y.o. [39–59], Sp0₂ 92% [90–95], WHO functional class II or III, mean pulmonary artery pressure 51mmHg [40–59]) were included between 2014 and 2018. All patients underwent MRI and echocardiography assessment. Echocardiographic measurements of RV remodelling and function included TAPSE, RV fractional area change (RVFAC), peak systolic velocity of the tricuspid valve (S’TV), right atrial (RA) area, RV strain, Systolic to diastolic ratio, eccentricity index and RVESRI, defined by septum length divided by lateral wall length. Pericardial effusion was noted.

Median RV ejection fraction (EF) evaluated with MRI was 46% [34–59]. RV dysfunction (RVEF<45%) was observed in 43% of patients. Median RVFAC and RVESRI were 29.6%[23–34] and 1.6[1.4–1.7] respectively. By spearman correlation, RVFAC and RVESRI were significantly correlated to RVEF (Rho 0.62, P<0.007 and Rho −0.51, P<0.02 respectively). By linear regression, RVFAC and RVESRI were also correlated to RVEF (R²=0.36, P<0.003 and R²=0.34, P<0.08). Pericardial effusion was associated with RV dysfunction (P<0.008) and a lower RVFAC (P<0.01). TAPSE, S’TV and RV strain were not correlated with RVEF.

RVFAC, RVESRI and pericardial effusion were markers of RV dysfunction in patients with ASD and severe PAH. RVESRI appears as a simple and reliable parameter for follow-up. Its prognostic value in patients with CHD remains to be demonstrated.