Atrioventricular Coupling in Children with Primary Hyperoxaluria Assessed by Three-Dimensional Echocardiography

All articles of this category (opens in new window) Background: Parameters of left atrioventricular (AV) coupling can give insight, especially into the diastolic function. We already established normative values of AV-coupling parameters in a healthy cohort using noninvasive real-time three-dimensional echocardiography (3DE). Now, we sought to examine and compare parameters of AV-coupling in a cohort of children with primary hyperoxaluria type 1 (PH1), in which accumulating oxalate can lead to an infiltrative cardiomyopathy. Methods: In 50 3DE datasets from 20 children with PH1 (aged 3.5–18 years), contributions of conduit volume, active and passive emptying volumes to left ventricular stroke volume (LVSV) were determined and compared with normative values from 279 healthy children. The PH1 group was further divided into examinations with and without abnormalities in 2D echocardiography (ejection fraction, strain, thickened septum, tissue doppler). Group differences were assessed using independent-samples t -tests or the Kruskal–Wallis test. Results: Analysis of all datasets of children with PH1 showed a significantly increased contribution of conduit volume to LVSV compared with normal values (64.2%±13.7% vs. 56.9 ± 7.8%) and reduced passive and active volumes (28 ± 12.1% vs. 32.9 ± 7.5% and 7.8 ± 4% vs. 10 ± 4.1%). PH1 children without abnormalities in 2DE already showed an increased contribution of conduit volume and decreased active emptying volume to LVSV. In children with abnormalities in 2DE, the conduit volume contribution increased further while the passive and active contributions significantly decreased ([ Table 1 ]). Table 1 Healthy cohort (median (IQR)) PH1 without abnormality in 2DE (median [IQR]) PH1 with abnormality in 2DE (median [IQR) Cond LVSV (%) 56.9 (11.3) 65 (17.7) 70.1 (10.9) Passive LVSV (%) 32.4 (11.8) 28.1 (16.2) 22.6 (8.2) Active LVSV (%) 9.6 (4.9) 7.7 (4.7) 6.4 (3.8) Conclusion: We observed differences in left ventricular AV-coupling between children with PH1 and healthy subjects. These differences were already present in subjects with otherwise normal 2DE data. With abnormalities in 2DE measurements, the altered AV-coupling was even more distinct. Subtle impairment of myocardial compliance might be revealed by AV-coupling parameters obtained from 3DE. Publication History Article published online: 17 February 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany