3-Dimensional echocardiographic evaluation of right ventricular function in pediatric sickle cell disease population

Abstract

Sickle cell disease (SCD) is characterized by chronic hemolytic anemia and intermittent vaso-occlusive events associated with cardiac abnormalities. To assess 3-dimensional (3D) echocardiographic of right ventricle (RV) volumes and function in a pediatric SCD population. Eighteen patients with SCD aged 4 to 17 years old (mean age: 8.0 ± 4 years, 56% male, body surface area (BSA) 1.0 ± 0.35) and 18 healthy controls matched for age, gender and BSA were prospectively included and compared. Echocardiograms were performed using a commercially available ultrasound Philipps EPIQ 9 system using matrix X5-1 transducer. 3D indexed RV volumes and ejection fraction (3D-RVEF) were obtained using full volume acquisitions. RV free wall strain, tricuspid S-wave, tricuspid annular plane systolic excursion (TAPSE), indexed cardiac output, systolic pulmonary pressure (sPAP) and hemoglobin were assessed. Data were finally analyzed with TomtecArena© software (v2.3), Germany. Cardiac output was significantly higher in SCD children (4.5 vs. 3.6 l/min/m 2 , P = 0.025), as sPAP (24.9 vs. 21.9 mmhg, P = 0.015), 3D-RV diastolic volume (58.1 vs 47.5 ml/m 2 , P = 0.0.25) and 3D-RV systolic volume (28.8 vs. 21.4 ml/m 2 , P = 0.005). 3D-RVEF and RV free wall strain were significantly altered in SCD compared to control population (respectively 51.9 vs. 56.3%, P = 0.018; − 28.6 vs. − 32, P = 0.017). There were no difference regarding TAPSE and Doppler S-wave. Mean hemoglobin in SCD population was 9.6 ± 1.7 g/dl. These findings suggest that 3D-RVEF and RV free wall strain are altered and associated to an augmentation of 3D-RV volumes, without alteration of longitudinal traditional RV parameters in this SCD population. Chronic anemia generating volume overload but also elevation of sPAP increasing RV afterload can explain these findings. This data need to be confirmed with cardiac magnetic resonance imaging.