Eccentricity Index Is Associated With Pulmonary Arterial Hypertension in Children After Repair of Complete Atrioventricular Septal Defects

Abstract

Introduction: Eccentricity Index is an echocardiographic predictor of disease severity in children with pulmonary arterial hypertension (PAH). Its utility after atrioventricular septal defect (AVSD) repair remains unclear due to surgical manipulation of the ventricular septum. We evaluated end-systolic (EIs) and maximal (EIm) as predictors of hemodynamics post-AVSD repair.

Methods: Cohort 1 was 89 children, 5-24 months after complete AVSD repair, and similarly aged controls. Subgroups of those with (+) and without (-) PAH were based on other echocardiographic markers of PAH. Cohort 2 was 20 children who underwent cardiac catheterization after AVSD repair. EIs and EIm were calculated as the ratio of the left ventricular diameter parallel to the septum divided by the perpendicular diameter measured at end systole and maximal post-systolic flattening, respectively.

Results: In Cohort 1, EIs and EIm in AVSD cases were greater than in controls. Both were highest in PAH(+) patients, followed by PAH(-), followed by controls. EIs predicted echo-estimated right ventricular systolic pressure, while EIm did not. In Cohort 2, EIs and EIm predicted RVSP ≥ 35 mmHg, while only EIs predicted PVRi ≥3 Wu*m². An EIs threshold of 1.28 optimally predicted elevated RVSP (AUC 0.761) and PVRi (AUC 0.779).

Conclusions: After AVSD repair, EIs and EIm are elevated compared to those of otherwise healthy children. However, significant elevation (Eis > 1.28) may still be useful to differentiate those with and without PAH. A multiparametric approach may be needed for borderline EIs (1.09-1.28). These findings support EI as a non-invasive screening tool to identify PAH in children after AVSD repair.

Keywords: atrioventricular septal defect; eccentricity index; pulmonary arterial hypertension.